chapter 37 pp Flashcards Preview

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Flashcards in chapter 37 pp Deck (76)
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1
Q

The Central Nervous System

A

Consists of the brain and spinal cord

2
Q

Hydras

A

Nerve net composed of neurons in contact with one another
Also in contact with contractile cells in the body wall
RELY ON THE FLOW OF WATER

3
Q

Planarians

A

Ladderlike nervocus system
Two ventrally located bundles of nerves extending from the cerebral ganglia to their posterior end
Cephalization – a concentration of ganglia and sensory receptors in the head (anterior region)
Bilateral symmetry and cephalization are two significant adaptive trends in nervous system development.

4
Q

Annelids and Arthropods

A

Complex animals
Typical invertebrate nervous systems
A brain is present and a ventral nerve cord has a ganglion in each segment.

5
Q

Molluscs

A

what is a mollusk? Snails oysters squids

Cephalopods have a well-defined brain and sense organs.

6
Q

Vertebrate brain is organized into three areas

A

hind brain, mid brain, forebrain

7
Q

Hindbrain

A

Regulates motor activity below level of consciousness

Medulla oblongata contains control centers for the heart and breathing

8
Q

Midbrain

A

The optic lobes are part of the midbrain.

Originally was a center for coordinating reflexes involving eyes and ears.

9
Q

Forebrain

A

In early vertebrate evolution, forebrain was concerned mainly with sense of smell.
In the forebrain, the hypothalamus is concerned with homeostasis and communicates with the medulla oblongata and pituitary gland.

10
Q

The hindbrain and midbrain of mammals are similar to those of

A

vertbrates

11
Q

The forebrain of mammals

A

is greatly enlarged

12
Q

neocortex

A

outer layer, only seen in mammals

13
Q

Forebrain in mammals functions for higher mental process

A

Spatial reasoning
Conscious thought
Language

14
Q

Frontal lobes in mammals

A

are large and complex in primates
Increased brain capacity allowed mammals, especially humans, to become adept at higher mental activities.
This provided tremendous evolutionary advantages.

15
Q

how is the nervous system separated?

A

in the central nervous system and Includes the brain and the peripheral nervous system.

16
Q

The peripheral nervous system (PNS)

A

Consists of all nerves and ganglia that lie outside the CNS
Two divisions
Somatic nervous system
Sensory and motor functions that control skeletal muscle
Autonomic nervous system
Controls smooth muscle, cardiac, muscle, and glands
Divided into sympathetic and parasympathetic divisions

17
Q

The central nervous system (CNS)

A

Includes the brain and spinal cord

18
Q

meninges

A

wha thte Spinal cord and brain are wrapped in three protective membranes

19
Q

cerebrosphal fluid

A

this is what fills the spaces

20
Q

ventricles

A

Fluid is continuous with that of central canal of spinal cord and the ventricles of the brain

21
Q

Meningitis

A

is a serious disorder caused by bacteria or viruses that invade the meninges.

22
Q

The Spinal Cord

A

Two main functions
Center for many reflex actions
Automatic responses to external stimuli
Means of communication between the brain and spinal nerves

23
Q

Composed of grey matter and white matter

A

Cell bodies and short unmyelinated fibers give the gray matter its color.
Myelinated long fibers of interneurons running in tracts give white matter its color.
White matter tracts connect spinal cord to brain

24
Q

Cerebral Cortex

A

A thin but highly convoluted outer layer of gray matter
Covers the cerebral hemispheres
Contains motor areas and sensory areas as well as association areas

25
Q

Primary motor area

A

is in the frontal lobe, just ventral to the central sulcus.

26
Q

Primary somatosensory area

A

is in the parietal lobe, just dorsal to the central sulcus.

27
Q

Basal nuclei

A

Integrate motor commands

Ensures that the proper muscle groups are either activated or inhibited

28
Q

Parkenson’s disease

A

Basal Nuclei
is a brain disorder characterized by tremors, speech, and difficulty standing and walking.
Results from loss of dopamine-producing cells in the basal nuclei

29
Q

Diencephalon Region

A

A region encircling the third ventricle

Includes three structures:Hypothalamus, Thalamus, Pineal gland

30
Q

Hypothalamus

A

Forms the floor of the third ventricle
Integrating center that maintains homeostasis
Controls the pituitary gland

31
Q

Thalamus

A

Consists of two masses of gray matter located in the sides and roof of the third ventricle
Receives all sensory input except smell
Integrates sensory information and sends it to the cerebrum

32
Q

Pineal gland

A

Secretes melatonin

Hormone involved in maintaining normal sleep-wake cycle

33
Q

Cerebellum

A

Separated from the brain stem by the fourth ventricle
Largest portion of the brainstem
Receives sensory input from the eyes, ears, joints, and muscles
Sends motor impulses out the brain stem to the skeletal muscles

34
Q

Brainstem

A

Contains the midbrain, pons, and the medulla oblongata

35
Q

Midbrain

A

Acts as a relay station for tracts passing between the cerebrum and the spinal cord or cerebellum
Pons

36
Q

Pons

A

Contains axons that form a bridge between the cerebellum and the rest of the central nervous system

37
Q

Medulla Oblongata

A

Contains reflex centers for vomiting, coughing, sneezing, hiccupping, and swallowing

38
Q

The Reticular Activating System (RAS)

A

A complex network of:
Nuclei (masses of gray matter)
Nerve fibers that extend the length of the brain stem
The reticular formation is a major component of the RAS.
The RAS arouses the cerebrum via the thalamus and causes a person to be alert.

39
Q

Limbic System

A

Complex network of tracts and “nuclei”
Incorporates
Medial portions of the cerebral lobes,
The basal nuclei, and
The diencephalon
Integrates higher mental functions and primitive emotions
Important structures in the limbic system are

40
Q

Memory

A

The ability to hold a thought in mind or recall events from the past

41
Q

Learning

A

Takes place when we retain and use past memories

42
Q

Short-term memory is associated with

A

the prefrontal area of the frontal lobe.

43
Q

Long-term memory is associated with

A

the hippocampus.
Gathers long-term memories stored in sensory association areas
Makes them available to the frontal lobe

44
Q

somatic system

A

vountary
Includes paired cranial nerves and spinal nerves
Gather information from sensors and conduct decisions to effectors
Controls the skeletal muscles

45
Q

autonomic system

A

(usually involuntary)
Controls the smooth muscles, cardiac muscles, and glands
Innervates all internal organs
Divided into two divisions
Sympathetic division
Parasympathetic division
Utilizes two neurons and one ganglion for each impulse

46
Q

Sympathetic division

A

Especially important during fight-or-flight responses
Accelerates heartbeat and dilates bronchi
Active muscles require a ready supply of glucose and oxygen
getting ready for the fight

47
Q

Parasympathetic division

A

Housekeeper
Promotes all internal responses associated with a relaxed state
Promotes digestion and retards heartbeat
more relaxing

48
Q

Neurons and neuroglia

A

are the two principal types of cells in neural tissue.

49
Q

Neurons (nerve cells)

A

Cell body
Dendrites
axon

50
Q

cell body

A

contains nucleus and organelles

51
Q

dendrites

A

receive signals from sensory receptors or other

neurons.

52
Q

axon

A

conducts nerve impulsesto another neuron or to other cells
Covered by myelin sheath
Any long axon is also called a nerve fiber.

53
Q

Astrocytes

A

help maintain neuron health.

54
Q

Microglia

A

are phagocytic cells that remove bacteria and debris.

55
Q

oligodendrocytes

A

in the CNS form the myelin sheath

56
Q

Schwann cells

A

in the PNS perform this function.

Gaps are nodes of Ranvier.

57
Q

Ependymal cells

A

line the ventricles of the brain, producing cerebrospinal fluid.

58
Q

Satellite cells

A

surround neuron cell bodies in ganglia.

Participate in responses to injury

59
Q

Types of Neurons

A

Sensory (afferent) neurons
Interneurons
Motor (efferent) neurons

60
Q

Sensory (afferent) neurons

A

Accept impulses from sensory receptors
Transmit them to the CNS
Unipolar

61
Q

Interneurons

A
Convey nerve impulses between various 
	parts of the CNS
Multipolar
Form complex pathways in the brain
Lead to higher mental functions
Thinking
Memory 
Language
62
Q

Motor (efferent) neurons

A

Accept nerve impulses from the CNS
Transmit them to muscles or glands
Multipolar

63
Q

Transmission of Nerve Impulses

A

Voltage is the measure of the electrical potential between two points.
Difference between electrode placed inside and another outside the axon

64
Q

Membrane Potential

A

An electrical potential difference across a membrane is called a membrane potential

65
Q

Resting Potential

A

The membrane potential when the axon is not conducting an impulse.
The inside of a neuron is more negative than the outside, around –70 mV.
Due in part to the activity of the sodium-potassium pump

66
Q

Transmission Across a Synapse

A

A synapse is a region where neurons nearly touch.
The small gap between neurons is the synaptic cleft.
Transmission across a synapse is carried out by neurotransmitters.

67
Q

Neurotransmitters

A

Acetylcholine
Norepinephrine
Dopamine
Serotonin

68
Q

Acetylcholine

A

In CNS and PNS, excites skeletal but inhibits cardiac muscle

69
Q

Norepinephrine

A

In CNS, important to dreaming, waking and mood

70
Q

Dopamine

A

In CNS, involved in emotions, learning, and attention

71
Q

Serotonin

A

In CNS, involved in thermoregulation, sleeping, emotions, and perception

72
Q

Neurotransmitter Removal

A

The postsynaptic membrane contains enzymes to inactivate the neurotransmitter.
Acetylcholinesterase breaks down acetylcholine.
Short existence of neurotransmitters at synapse prevents continuous stimulation or inhibition of postsynaptic membranes

73
Q

Synaptic Integration

A

A single neuron is on the receiving end of:
Many excitatory signals, and
Many inhibitory signals

74
Q

Integration

A

The summing of excitatory and

inhibitory signals

75
Q

drug abuse

A

Drug abuse – person takes a drug at a dose level that increases the potential for a harmful effect
Addiction – when more of the drug is needed to get the same effect
Withdrawal – when the user stops taking the drug

76
Q

Alcohol, drugs, and tobacco can all adversely affect

A

the developing embryo, fetus, or newborn