302 Exam 2: Sensory Systems, Somatic & Autonomic Pathways, Special Senses, Blood Flashcards Preview

A&P Lecture > 302 Exam 2: Sensory Systems, Somatic & Autonomic Pathways, Special Senses, Blood > Flashcards

Flashcards in 302 Exam 2: Sensory Systems, Somatic & Autonomic Pathways, Special Senses, Blood Deck (290)
Loading flashcards...
1
Q

What are special senses vs. general senses? How do they differ?

A

Special senses: Come from the head. Eyes, ears, taste, smell, equlibrium. General senses: Widespread.

2
Q

What are the primary divisions of the somatic sensory system? Of the visceral sensory system?

A

General somatic senses include somesthetic (skin) and proprioceptive (muscles & joints). General visceral senses include pain receptors (conscious/cerebrum) and blood pressure/osmolarity sensors (unconscious/brain stem).

3
Q

Where do graded potentials occur within most sensory neurons?

A

Trigger zone

4
Q

Are specialized sensory cells used by the general senses?

In the special senses?

Give examples.

A

Yes to both.

General: Tactile/Merkel cells in the skin.

Special: Rods & cones.

5
Q

What types of sensations utilize the simplest of sensory receptors?

A

The simplest sensory receptors use dendrites as free nerve endings to sense pain and temperature.

6
Q

What is a specific example of a nervous structure that utilizes pre-synaptic inhibition?

A

Inhibition of substance P via inhibitory neuron

7
Q

Are sensory tracts in the spinal cord ascending or descending tracts? Afferent or efferent?

A

sensory, afferent, dorsal, ascending

8
Q

What is another name for the graded potential that occurs in sensory neurons?

A

Receptor potential

9
Q

Define modality.

A

The type of stimulus, or the sensation it produces.

10
Q

Relative to the complexity of the sensory neuron or specialized sensory cell, where within this spectrum are Pacinian corpuscles?

Photoreceptors?

Pain receptors?

Why?

What modality does each detect?

A

From simplest to most complex:

  1. Nociceptors (pain) - free nerve endings
  2. Pacinian corpuscles (vibration) - encapsulated within other structures
  3. Photoreceptors (light) - specialized cells
11
Q

What type of sensory neuron is utilized by the general sensory system?

Where does it project to and what does it synapse on?

A

???

Primary (first-order) nerve fibers project from the PNS to the CNS (either the spinal cord or medulla oblongata).

From there, second-order nerve fibers project to the thalamus.

Finally, third-order nerve fibers project to the somatosensory cortex.

12
Q

What types of receptors (technical name) sense:

  • Pain?
  • Blood pressure?
  • Stretch of muscle?
  • Temperature?
  • Light?
  • Touch?
  • Proprioception?
  • Taste?
  • Smell?
  • Blood osmolarity?
A
  • Pain = Nociceptors
  • Blood pressure = Mechanoreceptors
  • Muscle stretch = Mechanoreceptors
  • Warm/cool temperature = Thermoreceptors
  • Light = Photoreceptors
  • Touch = Mechanoreceptors
  • Proprioception = Mechanoreceptors
  • Taste = Chemoreceptors
  • Smell = Chemoreceptors
  • Blood osmolarity = Chemoreceptors (Osmoreceptors)
13
Q

Define Transduction:

A

The process through which a physical stimulus becomes a graded potential in a sensor, then an action potential.

14
Q

In a “cool” receptor, how does an increase in temperature affect the AP frequency in the axon of the sensory neuron?

A

In a “cool” receptor, an increase in temperature would decrease the AP frequency in the axon of the sensory neuron.

15
Q

How does the depolarizing receptor potential occur in most sensory receptors?

What are some exceptions to this?

A

The graded potential in a sensory structure is usually due to Ca++ and Na+ channels opening in proportion to the signal.

Exceptions:

  • Photoreceptors (vision)
  • Chemoreceptors (taste & smell)
16
Q

Baroreceptors are a subtype of __________ receptors. What do they do?

A

Mechanoreceptors. They help regulate short-term blood pressure, becoming excited by stretch of the blood vessel.

17
Q
  • What type of channels are associated with detection of very high temperatures above 50 degrees celsius?
  • What else do they bind that opens them?
  • Does the opening of this channel cause a depolarization or hyperpolarization?
A
  • TRP channels within dendrites (specifically, the TRPV1 channel)
  • Also responds to capsaicin
  • Causes depolarization (Na+/Ca++ channel)
18
Q

In a mechanoreceptor in the skin, how does the graded potential compare between a light touch and a harder touch?

How does this affect the axon in each case?

A

The graded potential is proportional to the stimulus. A light touch means less stimulus, and therefore a lower-frequency AP in the axon. A heavier touch means more stimulus, resulting in a higher-frequency AP in the axon.

19
Q

Define dermatome:

A

A specific area of skin that sends sensory information to a specific spinal nerve

20
Q

What is the common language in the brain for all types of sensations? How does the brain discern one signal from another very different sensation?

A

Sensory coding is the brain’s common language for all types of sensations. Three signals are involved in sensory coding:

  1. AP frequency = intensity of stimulus
  2. Receptor modality = touch, vision, etc.
  3. Location of sensor = mapping via somatosensory cortex
21
Q
  • Within the somesthetic sensory system, what is the ultimate destination of the sensory neurons within the cerebrum?
  • How does this differ from the special senses relationship to the cerebrum?
A
  • Primary somesthetic cortex
  • ???
22
Q

Where do the primary, secondary, and tertiary sensory neurons synapse upon and in what location?

A
  • Primary: Spinal cord or medulla oblongata (myelencephalon)
  • Secondary: Thalamus (diencephalon)
  • Tertiary: Somatosensory cortex (telencephalon)
23
Q
  • Are baroreceptors within the aorta (major blood vessel coming out of the heart) consciously perceived?
  • If so, how?
  • If not, what is the destination of the sensory information?
A
  • No - pain is the only signal from the viscera that is consciously received.
  • N/A
  • Medulla oblongata
24
Q
  • Is pain within the viscera consciously perceived?
  • If so, how?
A
  • Yes, pain is the only signal from the viscera that is consciously perceived.
  • Via visceral dermatomes. Secondary neurons from both the viscera and skin receptors converge at the thalamus, where the tertiary neuron relays the signal to the area of the somatosensory cortex corresponding to the skin receptor.
25
Q

Define tonic and phasic sensory receptors and give examples of each?

A
  • Tonic sensory receptors are continuous, as long as stimulation exists. Example: pain.
  • Phasic sensory receptors experience more frequent AP stimulation at first, then taper off until no stimulation occurs as the neuron peripherally adapts. Once there is a change in the stimulation, APs resume firing. Example: Putting on, wearing, and removing a ring or necklace. Light touch.
26
Q

Where does pain project to?

A

Pain projects to four areas, which can be divided into two aspects:

  1. The somatosensory cortex of the cerebrum, where it is consciously perceived.
  2. Affective motivational aspects, including projections to the… Hypothalamus (directs SNS response)
  3. Limbic system (emotional response, memory)
  4. Reticular system (modulates levels of pain for the body to receive, aka central adaptation)
27
Q

Do phasic receptors utilize central or peripheral adaptation?

A

Central adaptation. (How does peripheral adaptation work?)

28
Q
  • What are the technical terms for fast vs. slow pain?
  • Which is chronic?
  • What has faster axons, and how are these axons referred to?
  • What fiber types are they comprised of?
  • What are some examples of fastest, medium, and slow sensory conduction speed?
A
  • Fast pain = first pain, acute, type Ia axons (faster), A-delta fibers (large, myelinated)
  • Slow pain = second pain, chronic, type Ib axons (slower), C fibers (small unmyelinated)
  • Fastest: Touch, proprioception
  • Medium: First pain, rough/indiscriminant touch
  • Slow: Second pain, chronic pain, temerature
29
Q
  • If an area of skin has high sensory discrimination, does this correlate with large or small receptive fields?
  • High or low receptor density?
  • In which areas of the body is discrimination the highest?
A
  • High sensory discrimination (aka acuity) = Small receptive fields
  • High receptor density
  • Highest in fingers, tongue/lips, genitalia, face, feet
30
Q
  • Are the mechanoreceptors associated with hair follicles tonic or phasic in nature?
  • Warm/cool receptors?
  • Proprioceptors?
A
  • Phasic???
  • Tonic
  • Tonic???
31
Q

Is an administered drug considered exogenous or endogenous?

A

Exogenous

32
Q

Define coding, and name the signals it involves.

A
  • Interpretation of perceived signals into meaningful information.
  • Involves:
    • AP frequency
    • Modality
    • Sensor location (mapping)
33
Q
  • Is adaptation to chronic slow pain an example of central or peripheral adaptation?
  • What is responsible for this type of adaptation?
A
  • Central adaptation
  • Reticular formation stops passing info to cerebrum???
34
Q

Define hyperalgesia:

A

Increased sensitivity to pain, generally caused by inflammatory “soup.”

35
Q
  • What brain structure is responsible for the majority of central adaptation?
  • What is the name of the associated tract?
A
  • Reticular formation
  • Reticulospinal tract
36
Q
  • How does lidocaine affect pain?
  • What other deficits would occur?
A
  • Lidocaine blocks APs by blocking voltage-gated Na+ channels (peripheral adaptation).
  • Also inhibits motor control, so if oral then drooling occurs.
37
Q

What are the four classes of endogenous analgesics?

A
  1. Enkephalins
  2. Endorphins
  3. Dynorphins
  4. Cannabinoids
38
Q

What class of drugs is primarily used to emulate the analgesia produced by endogenous sources?

A

Exogenous opiods

39
Q
  • What structure causes the descending output than causes central analgesia?
  • How does this specifically cause this?
A
  • Reticular formation
  • Stimulates inhibitory neuron via reticulospinal tract, which sends inhibitory pre-synaptic signal to the primary nerve fiber, preventing the release of substance P.
40
Q

What is a primary inflammatory mediator of hyperalgesia and how are these affected by NSAIDS?

A

Cox-forming prostaglandins, which induce hyperalgesia, are inhibited by NSAIDs.

41
Q
  • What are the side effects of exogenous opiates?
  • Which will probably kill a person first if overdose occurs?
A

Side effects of exogenous opioids:

  • Constipation
  • Respiratory depression – DEADLY
  • Addiction (pleasure centers stimulated)
42
Q

Arrange in order of conduction velocity:

  • Second pain
  • First pain
  • Proprioception
A

Fastest to slowest:

  1. Proprioception
  2. First pain
  3. Second pain
43
Q

Arrange in order of conduction velocity:

  • Temperature
  • Fine touch
  • Indiscriminant touch
A

Fastest to slowest:

  1. Fine touch (same as proprioception)
  2. Indiscriminant touch (same as fast pain)
  3. Temperature (same as slow pain)
44
Q

What are the three components of the muscle spindle organ?

A
  1. Nuclear bag fibers – primary afferent (Ia) fibers, phasic, length & speed
  2. Nuclear chain fibers – secondary afferent (Ib or II?), tonic, length only
  3. Gamma motor neurons – stimulate contractile ends of intrafusal fiber, prompting the previous sensory neurons to fire
45
Q

What are extrafusal fibers?

A

Standard skeletal muscle fibers that are innervated by alpha motor neurons and generate tension by contracting.

46
Q
  • What type of sensory information are nuclear bag fibers responsible for?
  • Nuclear chain receptors?
A
  • Nuclear bag – length and speed of stretch
  • Nuclear chain – just length
47
Q

What are gamma motor neurons used for?

A

Stimulate contractile ends of intrafusal fiber, prompting the previous sensory neurons to fire

48
Q

Which type of intrafusal fiber utilizes phasic sensory neurons?

A

Nuclear bag – responds to lengthening quickly

49
Q

What is the Gate theory of pain control?

A

The idea that non-noxious input closes the “gates” to nociceptive input, preventing it from projecting to the CNS. Ex: Rub it, kiss it, shake it, possibly run it under cold water.

50
Q
  • Does proprioceptive information ascend ipsilaterally or contralaterally?
  • Most tactile receptor information?
A
  • Proprioceptive info: ascends ipsilaterally via the spinocerebellar tract
  • Tactile info: ascends ipsilaterally via the dorsal tract
51
Q
  • Where do most mechanoreceptors decussate?
  • Temperature receptors?
  • Pain?
  • Indiscriminant touch?
  • Vibration?
  • Proprioception?
  • Which ascension paths do these each utilize, and do they ascend contralaterally or ipsilaterally?
A
  • Most mechanoreceptors and vibration receptors decussate at at the medulla oblongata, ascending ipsilaterally via the dorsal tract.
  • Most temperature, pain, and indiscriminate touch receptors decussate at the spinal cord immediately via their primary synapses, then ascend contralaterally via the anterolateral tracts.
  • Proprioceptive input decussates in spinal cord???, ascending ipsilaterally via the spinocerebellar tract.
52
Q
  • If you damage the entire right side of the spinal cord, what sensations will be lost in the right leg?
  • The left leg?
  • How does this differ if the dorsal columns are unaffected on the left side?

Reference the diagram from Purves, Neuroscience 5th Edition.

A

If damage the R side of spinal cord…

  • Sensations lost: R leg = proprioception, vibration, most tactile info
  • L leg = pain, temperature, indiscriminate touch
  • The dorsal colums carry tactile and vibration info ipsilaterally, so L dorsal colums would be carrying that info from the L leg. It would not make a difference.
53
Q

What are the spinocerebellar tracts associated with?

A

Proprioception

54
Q

What type of sensory receptor is found at the musculotendinous insertion?

How does it theoretically react to lifting very heavy weights?

A
  • Golgi tendon organs
  • Increased muscle tension compresses the GTOs inside the tendon, sending a sensory AP that results in a motor signal to inhibit muscle contraction. This has the protective effect of spreading force throughout the muscular cross-section.
55
Q
  • What are the two primary motor pathways?
  • Generally, what does each system stimulate?
A
  • Somatic motor = skeletal muscle
  • Visceral motor = smooth muscle, cardiac muscle, glands
56
Q

Where does planning of movement take place?

A

Primary motor cortex / pre-central gyrus / pre-motor cortex of frontal lobe???

57
Q

What is another name for alpha motor neurons?

A

Lower motor neurons

58
Q
  • Where does the corticospinal tract originate?
  • Where does it decussate?
  • What categories of neurons or groups of neurons does this tract synapse upon?
A
  • Pre-central gyrus = Upper motor neurons
  • Lateral tract at spinal cord, Fewer: Anterior tract at lower medulla o.
  • Lower (alpha) motor neurons

Voluntary contraction = Pyramidal system

59
Q

What is the primary neurotransmitter(s) used to stimulate lower motor neurons?

A

Glutamate

60
Q

Broca’s area, the motor planning center for speaking, projects to what part of the brain?

A

To the primary motor cortex, which then issues commands to the lower motor neurons

61
Q
  • Relative to the complex and simultaneous control of multiple muscles (both stimulation and inhibition), where does the coordination take place relative to “taking a step” versus “playing a tune on a piano”?
  • Which is innate and which is learned?
A
  • Taking a step is an innate pattern, takes place in the Central Pattern Generators of the spinal cord
  • Learned patterns, such as piano playing, take place in the Cerebrum
62
Q

Local circuit neurons often are grouped to stimulate or inhibit an entire muscle simultaneously. How does the “size principle” relate to variations in force that the muscle exerts?

A

x

63
Q

What would be more complex: a local circuit in the spinal cord, or a central pattern generator?

A

x

64
Q

What is/are the primary neurotransmitter(s) used to inhibit alpha motor neurons?

A

Glycine or GABA

65
Q

The corticospinal tracts descend directly from the primary motor cortex to the local circuit neurons in the spinal cord (or sometimes directly to the lower motor neurons), and this is also referred to as the pyramidal motor pathway. What is the function of extrapyramidal systems? What are three classic examples of them? What do they interact with (name three)?

A

Modification (correction) and execution of the conscious desire to move. 1.) Cerebellum 2.) Basal nuclei 3.) Reticular formation 1.) Central pattern generators 2.) Local circuit neurons 3.) Alpha motor neurons

66
Q

What system receives input from the sensorimotor cortex and modifies descending output via the thalamus?

A

x

67
Q

What system receives sensory input directly from peripheral sensors and modifies motor output via nuclei within the brainstem?

A

x

68
Q

What is hyperkinesia, and how does it sometimes occur? What is an example of this? Dyskinesia? Give three examples.

A

Excessive normal or abnormal movement which can result from damage to the basal nuclei. Ex: Chorea Dyskinesia = abnormal movement. Ex: Huntington’s chorea, dyskinetic cerebral palsy, Parkinson’s (loss of dopaminergic activity in basal nuclei).

69
Q

What is the integration center for a monosynaptic reflex?

A

The synapse is the integration center.

70
Q

What is the scientificky name for the stretch reflex?

A

Myotatic reflex

71
Q

Why is a track athlete penalized with a false start if he leaves the blocks 0.05 seconds after the gun fires?

A

x

72
Q

Is the entire stretch reflex monosynaptic?

A

No. There are multiple proprioceptors that each diverge to multiple alpha motor neurons which synapse in the spinal cord and either stimulate the motor pathway, ascend to the cerebellum, or stimulate an inhibitory neuron of an antagonist muscle.

73
Q

Diagram the stretch reflex including the sensory output and motor input to the muscle that is stretched, the motor output to the antagonistic muscle, and all synaptic connections including which are synapses that generate EPSPs or IPSPs

A

x

74
Q

Expand your diagram above to indicate that there are three motor units per muscle and assume all motor units in both muscles are affected by the sudden stretch of the muscle. Assume 1 spindle organ in this muscle?

A

x

75
Q

Which type of sensory pathway (there are two) from the muscle spindle is involved in the myotatic reflex?

A

???? Saladin

76
Q

What type of sensory receptor is involved in the flexor/crossed-extensor reflex?

A

Nociceptors???

77
Q

During the myotatic reflex, which muscle group (homonymous or antagonist) is affected first and why?

A

x

78
Q

Figure 13.22 in your textbook demonstrates the flexor and crossed-extensor reflex, draw this reflex arc to increase your own long term potentiation.

A

x

79
Q

Figure 13.22 in your textbook demonstrates the flexor and crossed-extensor reflex effect on the thigh ONLY. Which joints are flexed in response to the stimulus?

A

x

80
Q

If I step on a nail with my left foot, are the extensors or flexors of the right leg inhibited?

A

x

81
Q

If I touch a hot stove with a finger, utilize the terms “ipsilateral/contralateral” and “flexors/extensors” to detail the effects on the biceps brachii and the triceps brachii in each arm.

A

x

82
Q

If a doctor tested for the myotatic reflex in multiple muscle and it did not occur in any of them, what might this indicate?

A

x

83
Q

If the patellar reflex did not occur, and the doctor then proceeded to test the myotatic reflex in your biceps brachii and it was completely functional, what would this indicate?

A

x

84
Q

What types of axons (slow / medium / fastest) are involved in the pain-withdrawal reflex? Why? Is this a type C fiber?

A

x

85
Q

What is the purpose of the contralateral projection that occurs during the pain-withdrawal reflex when you step on a nail?

A

x

86
Q

What is a chromaffin cell/neuron? What structural type of a neuron is it?

A

??? – CLARIFY. Chromaffin cells are anaxonic post-ganglionic neurons found in the adrenal gland that secrete norepinephrine, about 80% of which is converted to norepinephrine by enzymes. Blood racing through near the chromaffin cells picks up the epinephrine and distributes it systematically.

87
Q

The autonomic nervous system is a Two Neuron Sequence: Fill in the table for the standard system (SNS vs. PSNS) below. Ignore exceptions. Pre-ganglionic Neuron (short or long?) Pre-Ganglion NT Post-synaptic receptor Post-Gang Neuron (short or long?) Post-gang NT Effector Receptors (general class and subtypes)

A

Pre-ganglionic Neuron (short or long?) SNS: short PSNS: long Pre-Ganglion NT SNS: ACh PSNS: ACh Post-synaptic receptor SNS: Nicotinic receptors PSNS: Nicotinic receptors Post-Gang Neuron (short or long?) SNS: long PSNS: short Post-gang NT SNS: Norepinephrine (adrenergic) PSNS: ACh Effector Receptors (general class and subtypes) SNS: alpha-1, beta-1, beta-2 (adrenergic) PSNS: Muscarinic (cholinergic)

88
Q

What NT does the pre-ganglionic neuron of the SNS secrete?

A

ACh

89
Q

What NT does the post-ganglionic neuron of the PSNS secrete?

A

ACh

90
Q

What NT receptor(s) is(are) found on effector organs responding to SNS stimulation?

A

Alpha-1, beta-1, beta-2 (adrenergic)

91
Q

What NT receptor(s) are found on the soma of post-ganglionic neurons of the SNS?

A

Nicotinic receptors

92
Q

Which are typically longer, SNS or PSNS pre-ganglionic neurons?

A

PSNS pre-ganglionic neurons

93
Q

Which neurotransmitters secreted within the autonomic nervous system act as antagonists to the receptors they target?

A

x

94
Q

What autonomic system is the adrenal gland associated with?

How is it exceptional?

A

Sympathetic NS

???

95
Q

What cranial nerve carries the majority of parasympathetic motor output?

Where does it arise?

A

Vagus (CN X)

Jugular foramen

96
Q

Are drugs or poisons sometimes antagonists to specific autonomic receptors?

A

x

97
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 agonist
g. Beta-2 agonist
h. Beta-2 antagonist

How would Atropine affect heart rate? Which category above is atropine?

A

Atropine dilates the pupils, which is an SNS function, so it would likely increase heart rate.

Atropine is a muscarinic antagonist, interfering with circular muscle constriction in the iris, a PSNS function. This allows the radial muscle of the iris to dominate.

The radial muscle of the iris has alpha-1 reception, so is it also an alpha-1 agonist?

98
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 receptor agonist
g. Beta-2 agonist
h. Beta-2 antagonist

Which drug category would be best to inhibit blood flow to the kidney?

A

Kidney function is governed by the PSNS, but not via PSNS stimulation. It is “always on,” until SNS inhibits it.

???

99
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 receptor agonist
g. Beta-2 agonist
h. Beta-2 antagonist

Assuming asthma includes an overstimulation and blocking of the airways/bronchi, which of these drug categories is best at treating the symptoms of asthma?

A

x

100
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 receptor agonist
g. Beta-2 agonist
h. Beta-2 antagonist

Which of the categories above would cause the pupil to constrict?

A

x

101
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 receptor agonist
g. Beta-2 agonist
h. Beta-2 antagonist

Which of the categories above most resembles epinephrine?

A

x

102
Q

Various drugs manipulate the autonomic nervous system. Choose from these categories for the following questions (Note: more than one may logically be correct)

a. muscarinic agonist
b. muscarinic antagonist
c. Alpha-1 antagonist
d. Alpha-1 agonist
e. Beta-1 antagonist
f. Beta-1 receptor agonist
g. Beta-2 agonist
h. Beta-2 antagonist

Which of the drug categories above would cause a decrease in cAMP within affected cells?

A

x

103
Q

Heroin causes pinpoint pupils. Which autonomic system does it generally stimulate?

A

Stimulate PSNS (inhibits SNS?)

104
Q

Which branch of the autonomic nervous system is the craniosacral division?

A

Parasympathetic

105
Q

Which branch of the autonomic nervous system are the paravertebral ganglia associated with?

A

Sympathetic

106
Q

Which branch of the autonomic nervous system has a greater degree of divergence within the ganglia?

A

Sympathetic. Greater divergence within the ganglia allows for a more explosive system.

107
Q

Which adrenergic receptor has the highest relative affinity for epinephrine vs. norepinephrine?

A

Beta-2

108
Q

Muscarinic receptors are named for a derivative of mushrooms that is an agonist for those receptors. How do you suspect mushroom poisoning affects you?

A

PSNS would be stimulated

  1. Drool (salivation is a PSNS function)
  2. GI pain (digestion is a PSNS function, so gut will churn and secrete)
  3. Sweating (this is a SNS function, but is activated by muscarinic receptors)
109
Q

IP3

What does an elevation of intracellular IP3 generally cause?

A

x

110
Q

In beta receptors, what does an elevation of cAMP cause to happen next in the intracellular pathways?

A

elevation of PKA (protein kinase A, which can either stimulate or inhibit muscle depending on the cellular pathway)

111
Q

If I wanted to mimic the effects of the PSNS exclusively, would it be better to use nicotine or muscarine? Why?

A

Muscarine, because all PSNS functions involve muscarinic receptors. Nicotine, on the other hand, stimulates both the PSNS and the SNS.

112
Q

The vagus nerve is associated with parasympathetic innervation. Transection of the vagus nerve causes an increase in the resting heart rate. Explain this relative to the normal (tonic) balance of autonomic forces on the heart rate at rest.

A

x

113
Q

How do alpha-1 receptors affect smooth muscle? Include intracellular 2nd messengers. Where does this happen?

A

Alpha-1 receptors are metabotropic GPCRs.

They stimulate phospholipase C, which stimulates inositol triphosphate (IP3), which opens Ca++ channels, increasing the concentration of Ca++ in the ICF. This leads to smooth muscle contraction.

Alpha-1 receptors are found on smooth muscle arterioles of the:

  1. Kidney
  2. GI
  3. Skin

We don’t need these functions during SNS stimulation, so vasoconstriction diverts energy to more pressing functions, such as getting blood to the heart and skeletal muscle (that’s why we don’t see alpha-1 receptors here).

114
Q

How do beta-2 receptors affect smooth muscle? Include intracellular 2nd messengers. Where does this happen?

A

Beta-2 receptors are GPCRs that increase cAMP (the most common 2nd messenger) to stimulate PKA (protein kinase A), which inhibits MLCK (causes smooth muscle contraction). This leads to relaxation of smooth muscle, often affecting vasodilation (increased bllod flow).

Found in:

  • Bronchioles, where we want to receive more air during SNS stimulation.
  • Skeletal muscle arterioles
  • Cardiac arterioles
115
Q

Propranolol is an beta adrenergic antagonist. Would this be better to treat high or low blood pressure?

A

Adrenergic receptors respond to adrenaline. They are usually stimulated by SNS activation, which generally increases blood pressure. An adrenergic antagonist would lower blood pressure, making propranolol (a “beta blocker”) better for treating high blood pressure.

116
Q

Do you sweat when pilocarpine (a muscarinic agonist) is administered? Why or why not?

A

Muscarinic receptors are found at all PSNS effector synapses. A muscarinic agonist would increase PSNS activity, and even though sweating is an SNS function it is exceptional in that sweat glands have muscarinic receptors. So yes, pilocarpine WOULD make you sweat.

117
Q

Does the rate of sweating increase when you smoke? Why or why not?

A

Nicotine stimulates the release of ACh, which in turn stimulates the muscarinic receptors on sweat glands, increasing sweating.

118
Q

Monoamine oxidase (MAO) is the enzyme in the cleft of adrenergic synapses, It removes the catecholamine from the synapse.

If you are taking a drug which is an MAO inhibitor, what does that do to the relative balance of autonomic function and why?

Would heart rate increase or decrease?

A

If MAO is a factor in adrenergic synapses, then it facilitates SNS activity.

An MAO inhibitor would therefore inhibit the SNS.

Heart rate increases with SNS activity, so an MAO inhibitor would decrease heart rate.

119
Q

Does cAMP generally cause stimulation or inhibition of smooth muscle?

A

cAMP stimulates PKA, which inhibits MLCK. MLCK causes smooth muscle contraction. Since cAMP indirectly inhibits MLCK, it therefore inhibits smooth muscle.

120
Q

Which organs are innervated by the sacral division of the autonomic nervous system?

A

Lower G.I.

Reproductive organs

121
Q

Which specific autonomic receptors cause each of these effects?

  1. _____ Bronchoconstriction
  2. _____ Heart rate increases
  3. _____ Renal blood vessel vasoconstriction
  4. _____ Bronchodilation
  5. _____ Lipolysis
  6. _____ Heart rate decreases
  7. _____ Stimulate exocrine glands (salivary, pancreas)
  8. _____ GI inhibition
  9. _____ Stimulate CNS/brain
  10. _____ Complex pre-synaptic effects
  11. _____ Vasoconstriction in skin
A
  1. M3
  2. Beta-1
  3. Alpha-1
  4. Beta-2
  5. Beta-3
  6. M2
  7. M1
  8. Alpha-1
  9. M4/M5
  10. Alpha-2
  11. Alpha-1
122
Q

What are varicosities?

How do they differ from a typical neuron-neuron synapse?

A

Varicosities are a sort of post-synaptic terminal consisting of sequential beads that “slather” smooth muscle in NT.

They are less specific than a typical neuron-neuron synapse. Also, varicosities do not show divergence.

123
Q

Why are there several isoforms of cholinergic and adrenergic receptors if they all respond to the same neurotransmitters?

A

Diferent receptors are what yield the different effects.

124
Q

Which receptors in the autonomic nervous system are ionotropic?

Metabotropic?

A

Ionotropic:

  • Nicotinic

Metabotropic:

  • All Alpha
  • All Beta
  • All Muscarinic isoforms
125
Q

If a complex set of sensory stimulation causes SNS activity to increase, what else does it generally cause?

A

Suppression of kidney activity and other “housekeeping” functions

126
Q

What causes the activity of the kidney to increase and decrease at different times?

A

The kidney’s default state is “on,” even though it receives no PSNS innervation. It is innervated by the SNS, which inhibits its function.

127
Q

Which isoforms of the muscarinic receptors are most associated with smooth muscle?

Cardiac muscle?

Exocrine glands?

The CNS?

A

Smooth muscle = M3

Cardiac muscle = M2

Exocrine glands = M1

CNS = M4/M5

128
Q

What part of the autonomic nervous system causes blood flow to the genitalia to increase and how?

A

Everywhere else, muscarinic receptors induce contraction. In the the genitalia, ACh stimulates muscarinic receptors, which stimulates the release of Nitric Oxide, which relaxes the reproductive smooth muscle, facilitating vasodilation.

129
Q

What part of the autonomic nervous system causes the iris to dilate and how does it cause this?

A

The SNS stimulates radial smooth muscle of the iris via Alpha-1 receptors, causing them to contract, pulling the pupil wider.

130
Q

What part of the autonomic nervous system causes the iris to constrict and how does it cause this?

A

The PSNS causes the circular smooth muscle of the iris to contract via muscarinic receptors, causing pupillary constriction.

131
Q

What part(s) of the brain are responsible for modulating autonomic motor output?

A

SNS: Hypothalamus

PSNS: Brain stem

132
Q

What can cause activation or inhibition of the autonomic pathways, visceral sensations or conscious impulses or both?

A

Both

??? more detail

133
Q

Relative to olfaction, what is the purpose of the nasal conchae (turbinate bones)?

A

????

134
Q

Describe the properties of the olfactory epithelium:

A

Olfactory epithelium, found within the nasal cavity, makes up the seromucus membranes. Molecules can dissolve within the mucus secretions, while the watery secretions humidify.

135
Q

What chemical properties make odorants especially well perceived?

A

Fats are lipid-soluble, while salts are water-soluble – note that neither of these smell very strongly. Something that is strongly smelled is neither too lipid-soluble or too water-soluble.

136
Q

Describe the neural pathway by which olfaction is perceived consciously:

A

Molecular receptors of bipolar neurons (PNS)

–> through cribiform plate of ethmoid via olfactory foramina

–> synapse on olfactory bulb (CNS)

–> Olfactory tract

–> Bypasses thalamus, spilts to Limbic System (direct emotional stimulation) and Olfactory cortex of the Frontal/Temporal Lobe (taste association)

137
Q

How many olfactory neurons do you possess?

A

10-20 million

138
Q

What is cranial nerve I composed of and where is it found?

A

CN 1 is composed of tiny bipolar neurons that travel through the cribiform plate of the ethmoid bone via the olfactory foramina to synapse on the olfactory bulb.

139
Q

Besides the primary olfactory cortex, where does the olfactory pathway project to in the brain?

A

Limbic system (direct emotional stimulation)

140
Q

Approximately how many types of olfactory neurons are there?

Relative to this number, how many “scents” can we actually differentiate and how does this occur?

A

50 different types of olfactory receptors

2000-4000 different smells perceivable due to convergence within the olfactory bulb

141
Q

What types of papillae are found on the human tongue and which contain the most to least taste buds?

A

Most to least taste buds:

Circumvallate papillae (back of tongue, 100 buds/pap)

Fungiform papillae (side of tongue, 5 buds/pap)

Filiform papillae (no taste buds)

142
Q

Describe the structure of an olfactory receptor and the direct effect it has (the molecule):

A

Olfactory receptors are bipolar neurons with dendrites covered in cilia (approx 20/cell) which increase surface area, allowing for more receptors to bind odorants.

143
Q

What is the odorant that acts as a human pheromone?

A

???

144
Q

Are all genes that code for olfactory receptors expressed?

A

1000 genes code for chemoreceptors, and humans produce as many as a dog but we don’t express nearly as many.

145
Q

Which 2nd messenger is stimulated by an odorant, and what does it cause?

A

Odorant binding to receptor causes an increase in cGMP, which opens cGMP-gated channels, allowing Na+ to enter and depolarization to occur. This generates a graded potential which becomes an AP.

146
Q

Diagram a taste bud and the relative structures defined in class:

A

Should include:

  • Outer portion with taste hairs converging through a taste pore
  • Inner portion, bulbous with taste cells and stem cells vaguely designated within.
147
Q

Which cranial nerves carry information from the taste buds?

A

CN 7, 9, 10 perceive taste from taste buds

148
Q

Where in the cerebrum do taste buds pathways project?

A

Gustatory cortex of the insula

149
Q

What other cranial nerves are involved in “taste” and how?

A

CN 1 = olfaction

CN 5 = texture and fat

150
Q

What are the primary “tastes” we can perceive?

A
  1. Sweet
  2. Salty
  3. Sour
  4. Bitter
  5. Umami (glutamate)
151
Q

How is the taste of fat primarily perceived?

A

As texture via CN 5 (Trigeminal)

152
Q

Name three types of papillae on the tongue.

Which is not involved with taste?

Which has the most taste buds?

A

Filiform papillae (no taste buds)

Fungiform papillae (only 5 taste buds)

Circumvallate papillae (most taste buds - 100)

153
Q

What taste is perceived via umami receptors?

A

Glutamate: Broth, parmesan, marrow, soy sauce, MSG

154
Q

How many taste buds are there in a person?

A

10,000

155
Q

What is the purpose of filiform papillae and where are they found?

A

Friction for tongue to grab/move food, mostly toward front of tongue

156
Q

What receptor senses really hot/spicy foods?

A

????

157
Q

Describe the function of the orbit and adipose tissue within:

A

Mechanical insulation (protection)

158
Q

What is a chalazion and what does it result from?

A

x

159
Q

What is the scientificky name for eyelids?

A

Palpebrae

160
Q

Which cranial nerve innervates the levator palpebrae superioris?

The iris smooth muscle?

A

????

161
Q

Which cranial nerve innervates most of the extrinsic eye muscles?

A

CN III: Oculomotor

162
Q

What is the function of eyebrows?

Eyelashes?

A

Eyebrows: ???

Eyelashes: Protection

163
Q

What does stretch of the palpebral hair follicles cause to happen?

A

x

164
Q

What are conjunctivae and where are they found?

A

The conjunctiva lines the inside of the eyelid and covers the sclera. It helps lubricate and clean the eye.

165
Q

Where are the lacrimal punctae found?

A

x

166
Q

What is the composition of tears?

Is the lacrimal gland exocrine or endocrine in nature?

A

x

Exocrine

167
Q

From a purely circulatory perspective, why do you cry?

A

The rate of production of tears is greater than the rate of removal. The overflow = crying.

168
Q

What part of the brain integrates the pupillary reflex?

What cranial nerves are involved?

A

Shine light into eyes: Received by CN II (optic)

Integration: Superior colliculi

Consensual constriction: Via CN III (oculomotor)

169
Q

What cranial nerves are involved in the corneal blink reflex?

Where is this reflex integrated?

A

Opthalmic branch of Trigeminal (CN V) receives tactile and nociceptive input

Integrates where???

Motor output via Oculomotor (CN III) causes consensual blinking

170
Q

True or False: A cataract is a cloudy cornea?

A

False

Cataract = cloudy lens due to denatured proteins

171
Q

What are the three “tunics” of the eyeball? What are their components?

A

REFER TO LAB PRESENTATION TO CHECK

Fibrous tunic

  • Sclera
  • Cornea

Vascular tunic

  • Choroid
  • Ciliary body
  • Iris

Nervous tunic

  • Retina
172
Q

What is the most common protein in the sclera?

Where is the sclera thickest and why?

A

?????

??? Thickest near exit of optic nerve, to compensate for lack of structural integrity near opening.

173
Q

Why is the cornea avascular?

How are oxygen and nutrients obtained?

A

Why????

Oxygen and nutrients are obtained via diffusion.

The outer cornea receives O2 directly from the atmosphere, while the inner cornea receives it from the aqueous humor.

174
Q

Is accommodation a function of the cornea?

Is refraction a function of the cornea?

A

Accommodation is due to the balance between the ciliary muscle and the lens.

The cornea does refract (bend) light, but we don’t manipulate it to focus. The lens is manipulated for focusing.

175
Q

Lens transplants are common and relatively easy. What anatomical characteristics of the lens make it suitable for easy transplant?

A

Avascular????

176
Q

Define “zonular fibers”:

A

x

177
Q

Does LASIK surgery alter the shape of the lens?

A

No, the cornea

178
Q

What supplies blood to the outer layers of the retina? The inner layers?

A

x

179
Q

What tunic is the iris part of?

How does melanin affect eye color?

Why are albino irises red?

A

Vascular tunic

Pigmented cells of iris contain melanin, affect eye color

Albino irises lack melanin, so the color of the vasculature comes through

180
Q

How is the intrinsic muscle of the iris arranged? What type of muscle is this?

A

x

181
Q

Which cranial nerve innervates the ciliary muscle?

A

x

182
Q

How does contraction of the ciliary muscle affect the shape of the lens?

A

The ciliary muscle forms a ring around the lens, whose elastic nature allows it to stretch outward pulled by the suspensory ligaments. Contraction of the ciliary muscle pulls the lens inward, making for a more rounded lens.

183
Q

What is the function of ciliary processes?

A

Secrete aqueous humor

184
Q

How would blockage of the scleral sinus (canal of schlemm) affect the eye?

A

When these clog, a sty forms

??

185
Q

How does glaucoma affect the eye?

A

When input of aqueous humor exceeds output, ocular pressure increases – this is glaucoma. Too much pressure will cause the ocular neurons to fail (most neurons fail under pressure).

186
Q

Are rods or cones used to detect color?

A

Cones

187
Q

What is(are) the purpose(s) of the pigmented epithelium?

A

Melanin of the pigmented epithelium absorbs light, which:

  • Prevents reflection
  • Increases visual acuity
  • Absorbs/recycles used photopigments (maintenance function)
188
Q

What type of radiation is more damaging to skin, ultraviolet or infrared? Why?

A

UV light has a shorter wavelength, indicating a higher frequency, which packs more energy. UV light is therefore more damaging to skin.

189
Q

What wavelengths of the electromagnetic spectrum are perceived as visible light?

A

Violet (400 nm) to Red (750 nm)

190
Q

How many types of cones are found in the human retina?

A

3 types of cones, with differing opsins

191
Q

How many photoreceptors are found in both eyes?

Bipolar neurons?

Ganglionic neurons?

A

Photoreceptors: 130 million x 2 = 260 million

Bipolar neurons: 6 million x 2 = 12 million

Ganglionic neurons: 1 million x 2 = 2 million

192
Q

What does the above answer (about # of photoreceptors, bipolar neurons, and ganglionic neurons) most clearly indicate relative to this pathway?

A

Since photoreceptors receive light first and are of far greater number than the ganglionic neurons which become the optic nerve, this indicates convergence and integration within the retina which allows for a smaller optic nerve.

193
Q

Which neurons facilitate communication between the photoreceptors and bipolar neurons?

Between the bipolar neurons and the ganglionic neurons?

A

Horizontal cells

Amacrine cells

194
Q

Where in the retina are only cones found?

Where are only rods found?

A

Only cones are found in the fovea.

Only rods are found ???

195
Q

Would you describe red light as having a relatively high or low frequency?

A

Red light has a relatively low frequency (longer wavelength, lower energy)

196
Q

Where in the retina is the blind spot found?

A

Where the convergence of ganglionic axons called the Optic Nerve exits the eye

197
Q

Does orange glass transmit/absorb/reflect blue light?

A

x

198
Q

Does a purple shirt transmit/absorb/reflect light of approximately 400 nM wavelength?

A

x

199
Q

What type of visible light do “white things” absorb?

A

x

200
Q

What color only activates a single type of cone?

A

x

201
Q

Is neural convergence or divergence a charactistic of the retina?

A

Convergence

202
Q

Describe the complete pathway of conscious optic perception.

A

??? Is there unconscious optic perception?

Optic nerve

–> Optic chiasm

–> Optic tract

–> Thalamus (lateral geniculate nucleus) to visual cortex (occipital)???

Also diverges to various reflex pathways.

203
Q

Why do white things still get hot in the sun?

A

x

204
Q

What are the light sensitive molecules in photoreceptors called?

How does light striking that molecule affect it?

What does this cause?

A

Rhodopsin (photopigment)

Light striking rhodopsin causes an increase in cGMP. ???

Increase in cGMP breaks rhodopsin down into opsin and retinal, decreasing cGMP as 2nd messenger (???)

205
Q

Using the color version of the diagram below, what is the combined signal that the brain perceives as “aqua”?

A

x

206
Q

How well do you think you would be able to spot a red parrot in the jungle on a dark night? Why?

A

x

207
Q

What part of the photoreceptor differs most between red and blue cones?

A

x

208
Q

Does cGMP increase or decrease in a photoreceptor when suddenly exposed to light?

A

cGMP decreases as it is hydrolyzed when suddenly exposed to light

????

209
Q

What is the effect of high levels of cGMP in a photoreceptor?

A

x

210
Q

Are photoreceptors more hyperpolarized in the dark or the light?

A

We have 125 million rods vs. 6 million cones. During the day, most rods are “bleached,” hyperpolarizing them to the point where they cease NT secretion and stop functioning.

211
Q

Is more neurotransmitter secreted by photoreceptors in the dark or the light?

A

In the dark, the decrease of free opsin increases free cGMP, which opens cGMP-gated channels = depolarization, increased NT (glutamate) release, and decreasing AP frequency in the bipolar neuron.

212
Q

Does depolarization still cause release of neurotransmitter in a photoreceptor, as in most neurons?

A

???

213
Q

What neurotransmitter is secreted by photoreceptors? What effect does it have on the bipolar neurons?

A

x

214
Q

Is the AP frequency in bipolar and ganglionic neurons higher in the dark or in the light?

A

AP frequency is higher in the light, lower in the dark

215
Q

How does relaxation of the ciliary muscle affect the shape of the lens?

Is this better for near or far vision?

A

Relaxation of the ciliary muscle allows the elastic nature of the lens being stretched outward to dominate, making for a flatter lens.

This is better for far vision.

216
Q

Is near or far vision more compromised if a person has myopia?

A

Myopia = near sighted

So, far vision is more compromised

217
Q

What type of vision causes eye fatigue and why?

A

Close vision requires contraction of the ciliary muscle, requiring energy, causing the eye to fatigue.

218
Q

How does age often affect vision and why?

A

We often become more hyperopic as we age.

Decreased eleasticity overall also affects the lens, making it stay flatter and more stretched out.

219
Q

What nucleus transmits visual information to the cerebrum?

What part of the cerebrum does it go to?

A

Lateral geniculate nucleus???

Thalamus to visual cortex???

220
Q

What connects the lens envelope to the ciliary body and ciliary muscle?

A

Suspensory ligaments

221
Q

When something is in your left binocular field of vision, what part of the cerebrum processes that image?

A

R cerebrum processes info from left binocular field of vision

222
Q

Which eye perceives something within your right peripheral (monocular) field of vision?

A
223
Q

Is the projection of the medial retina ipsilateral or contralateral?

A

Contralateral

224
Q

Besides the cerebrum, where else does visual information go?

What general effect does visual information have in each of these places?

A

Pre-tectum = Pupillary reflex

Superior colliculus = Other visual reflexes

Hypothalamus –> Suprachiasmatic nucleus = Circadian rhythms

Cerebellum = Coordinates vision w/motion, balance, equilibrium

225
Q

Where is the ocular reflex integrated?

A

x

226
Q

Which part of the ear (outer/middle/inner) is not filled with air?

A

The inner ear (fluid-filled)

227
Q

What connects the throat to the middle ear? Why?

A

???

228
Q

Does air enter or exit the middle ear when ascending in a hot air balloon?

A

x

229
Q

Define otitis media. How does this potentially affect hot air balloon ascending?

A

x

230
Q

Which two places does the language association center (Wernicke’s area) receive information from?

A
  1. Primary auditory cortex of the temporal lobe
  2. Visual cortex? Lat geniculate nucleus???
231
Q

What are the two smallest synovial joints in the human body?

A

x

232
Q

What muscles are found within the middle ear?

When and why do they contract?

A
  1. Stapedius
  2. Tensor tympani

???

233
Q

Define acoustic reflex:

A

x

234
Q

What is the normal range of human hearing in a young person?

How does the range usually change with age?

A

20 Hz - 20 kHz (20,000 Hz)

???

235
Q

What is the sensory cell of both the cochlea and utricle?

A

Hair cells?

236
Q

How does transduction occur when a hair cell is bent by the sound?

A

Sound (air) waves

Fluid waves

Basilar membrane shifts

Hair cells bend

Send AP

AP stimulates cochlear nerve

237
Q

How is a high pitch differentiated from a low pitch relative to cochlear nerve action potentials?

A

???

238
Q

How is a loud low pitch differentiated from a quieter sound of the same low pitch?

A

x

239
Q

Which would be the higher pitch sound: 30 Hz or 1 kHz?

A

1 kHz = 1000 Hz, so 1 kHz would be the higher pitch

240
Q

Which would be an example of ultrasound: 10 Hz or 30 kHz?

A

Ultrasound is a very high frequency, in the 20+ kHz range? So 30 kHz would be an example of ultrasound.

241
Q

What structural type of neurons do hair cells communicate with?

Where do these neurons project to within the brain?

A

Bipolar neurons

To cochlear nuclei of pons/medulla oblongata (and/or olivary complex?)

242
Q

What part of the brain is most responsible for auditory localization of sounds?

A

x

243
Q

What part of the brain is most responsible for the startle reflex causing you to look towards a sudden surprising sound?

What does the motor output of this reflex affect?

A

Inferior colliculi (responsible for most auditory reflexes)

Necks muscles (via hypoglossal nerve)

244
Q

Where is the primary auditory cortex?

A

Temporal lobe

245
Q

If I turn my head to the right while focusing on the letters of this problem set, which way do my eyes move?

What reflex governs this?

A

To the left

Vestibulo-ocular reflex

= “SC” (superior colliculi or semicircular canals?) to extrinsic eye muscles

246
Q

When your alarm clock wakes you up at 5 am to study A&P, which part of your brain should you blame most for waking you up? Hint: Not the conscious portion that chose to register for the course.

A

x

247
Q

Describe the neural pathway by which auditory information gets from the cochlear nerve to the primary auditory cortex.

A

Hair cells

Bipolar neurons

Cochlear nerve

Cochlear nuclei of pons/medulla oglongata

Olivary complex (timing/binaural complex)

Inferior colliculi (most auditory reflexes)

Primary auditory complex (tonotopic mapping)

Wernicke’s area (language integration center)

248
Q

Which two systems are coordinated by the vestibulo-ocular reflex?

A

x

249
Q

Which of the special senses project to the cerebellum?

A

Equilibrium

250
Q

What do the semicircular canals detect, rotational velocity or rotational acceleration?

A

Rotational acceleration

251
Q

Which specific part of the vestibular apparatus detects rapid sudden movement upward in an elevator? Assume you are not laying down in the elevator.

A

Saccule = vertical acceleration/decceleration

(vs. Utricle = horizontal)

252
Q

Assuming rotational acceleration causes a depolarization in the right horizontal semicircular canal and a consequent increase in AP frequency within the vestibular nerve leading away from it, what would rotational deceleration cause in the left horizontal semicircular canal?

A

???

253
Q

Which system detects gravity?

A

Vestibular system

(includes the utricle and saccule)

254
Q

What is the primary difference between the utricle and a semicircular canal?

A

x

255
Q

When sitting upright in a moving automobile at a constant speed, which part of the vestibular apparatus would have the greatest frequency of action potentials ?

A

Utricle

256
Q

What are the primary targets of vestibular pathways in the brain?

A

Cerebellum (integrates movement)

Cerebrum (diffuse primary cortex / insula)???

257
Q

Is transduction by the hair cells of the saccule almost the same as in the cochlear hair cells?

Is the neuron they communicate with pretty much the same structurally?

A

x

258
Q

Is there conscious perception of the output from your semicircular canals?

A

Yes???

Via cerebrum: Diffuse primary cortex, insula

259
Q

What is the primary function of blood?

What are the multiple other functions which blood serves?

A

Transport in/out of tissues

Also:

  • Temperature regulation
  • Interstitial regulation??
  • Immune transport
  • Clotting
260
Q

What components of blood participate in immune function?

A

Plasma:

  • Plasma proteins
    • Globulins (aka antibodies, immunoglobulins

Formed elements:

  • Leukocytes
261
Q

Define Whole Blood and the various subcomponents within:

A

Whole Blood

  • Plasma (55% of whole blood)
    • Water (92% of plasma)
    • Plasma proteins (7% of plasma)
      • Albumin (60% of plasma proteins)
      • Globulins (35% of plasma proteins)
      • Fibrinogen (5% of plasma proteins)
    • Solutes (<1% of plasma)
      • Electrolytes
      • Organic nutrients
      • Organic wastes
  • Formed Elements (45% of whole blood)
    • Erythrocytes (99.9% of formed elements)
    • Leukocytes
    • Thrombocytes
262
Q

How does volume relate to pressure in the blood supply and elsewhere?

A

Increased volume = increased pressure

263
Q

If you infuse a person with 2 liters of plasma, the person will be ________-volemic and ________-tensive.

A

Hypervolemic, hypertensive

264
Q

What other system most directly regulates blood pressure?

A

Cardiovascular system regulates blood pressure directly in acute cases

265
Q

What other system most directly regulates blood volume?

A

Renal system directly regulates blood volume, affecting blood pressure indirectly over the long-term

266
Q

Is whole blood intracellular or extracellular fluid?

A

x

267
Q

What approximate percentage of whole blood is water?

Plasma?

Formed elements?

Plasma Proteins?

A

(0.55 plasma/whole blood) x (0.92 water/plasma) = 50.6% water/whole blood

55% plasma/whole blood

45% formed elements/whole blood

(0.55 plasma/whole blood) x (0.07 plasma proteins/plasma) = 3.85% plasma proteins/whole blood

268
Q

What are the basic types and functions of the “big three” plasma proteins?

A
  1. Albumin - osmotic pressure, carries hydrophobic molecules
  2. Globulin - antibodies, immune function
  3. Fibrinogen - clotting/coagulation
269
Q

How and why would a liver disorder affect clotting, immune function, and osmotic balance?

A

The liver produces most of the proteins in the blood, including the “big 3” plasma proteins which affect clotting (fibrinogen), immune function (globulins), and osmotic balance (albumin). Therefore, a liver disorder would hinder all of these functions.

270
Q

Besides plasma proteins, what types of solutes are found in plasma? Give examples of each.

A

Electrolytes: Na+, K+, Ca++, Cl-, HCO3- (what about H+???)

Organic nutrients: Glu(cose???), free amino acids, lipids

Organic wastes: Creatinine/urea, dissolved gases such as CO2, O2, NO, H2S

271
Q

What are the categories of formed elements and what is an approximate count for each? (per microL)

A

Erythrocytes = 5 million / microL

Leukocytes = 10K / microL

Thrombocytes = 130K-330K / microL

272
Q

What is the primary function of red blood cells?

A

Transport O2 and CO2 via hemoglobin

273
Q

What are the technical names for red blood cells, white blood cells, and platelets?

A

RBCs = erythrocytes

WBCs = leukocytes

Platelets = thrombocytes

274
Q

There are approximately 24 trillion (24,000,000,000,000) red blood cells in an average sized human. If red blood cells have an approximate 120 day lifespan, how many red blood cells are destroyed, and thus also formed, in a single day?

A

200 billion RBCs destroyed/formed each day

275
Q

Besides the “big three plasma proteins”? What other substances in blood might be proteins?

A

Hormones

Enzymes

Clotting factors (???)

Complement (???)

What about free amino acids?

276
Q

What part(s) of the body is responsible for breakdown and recycling of the components of the red blood cells when they die?

A

Spleen & liver

277
Q

What limits erythrocytes from having a longer lifespan?

A
278
Q

What is the shape and size of a red blood cell? Why this size?

A

Shape?

8 microM wide = ??? width of capillary

2-3 microM thick = ???

279
Q

What are three separate ways used to clinically quantify your oxygen carrying capacity?

What is an approximate normal value for each?

Are they equal in both sexes?

Did you remember to put units on those numbers?

A

CBC (???) = 15g Hb/dL

MCV (Mean Corpuscular Volume) = HCt/RBC # = 84-96 femtoL??? = normocytic, can be microcytic or macrocytic

MCHC (Mean Corpuscular ???) = [Hb]/HCt = 32-36% = normochromic, can be hypochromic but no such thing as hyperchromic

280
Q

What does a low mean corpuscular volume indicate?

What is the clinical term for cells of this type?

How is MCV estimated?

A

Low MCV indicates…???

Microcytic erythrocytes

HCt / # of RBCs

281
Q

Can you be anemic if your hematocrit is normal?

What clinical measure might indicate this condition?

How would you describe the erythrocytes in this condition?

A

x

282
Q

What are the two very distinct ways in which you can become anemic?

A

x

283
Q

What are some distinct ways in which anemia can occur due to a hypoproliferative cause?

A

x

284
Q

How would autoimmune destruction of red blood cells affect the body and what is the response of the body?

A

x

285
Q

What is a normal leucocyte count?

A

10k / microL

286
Q

What does the white blood cell differential measure?

A

x

287
Q

What is the term for white blood cell formation?

Where does this occur?

If you had to invent a name for a hormone which caused this, what would you call it in order to maintain consistency of the bloodish hormones?

A

x

288
Q

Where are lymphocytes formed?

A

x

289
Q

What is a normal thrombocyte count and why might we encounter a low count?

A

x

290
Q

Describe the structure of thrombocytes and the cell from which they originate. Are they long lived? why or why not?

A

x