What is the basic structural unit of a muscle?
Muscle Fiber (Cell)
Which connective tissue structure surrounds an individual muscle fiber?
Endomysium
Muscle fibers are grouped into bundles known as ___.
Fasciculi
Which structure surrounds a fasciculi: endomysium, perimysium, or epimysium?
Perimysium
Which connective tissue structure continues as the tendon of a muscle?
Epimysium
T/F: Skeletal muscle fibers are multinucleated.
True
Which of the following is an increase in the size of a muscle: hypotrophy, hypertrophy, hypoplasia, hyperplasia?
Hypertrophy
Which fiber type is associated with endurance activities and aerobic metabolism?
Type 1
Which fiber type has more capillary beds and more mitochondria?
Type 1
Type II muscle fibers use ____ metabolism.
anaerobic
Type __ are considered “fast twitch” muscles.
Type II
What is the name of the muscle cell membrane?
Sarcolemma
What is the function of the sarcoplasmic reticulum?
Store and transport calcium ions
What protein pigment gives color to muscle and stores the oxygen needed for the muscle?
Myoglobin
What is the smallest functional unit of the myofibril?
Sarcomere (Z-line to Z-line)
What is the thin, dark line down the center of each H-band: I-band, A-band, M-band, or Z-line?
M-band (M=middle)
Actin is found mainly in the _-bands and myosin is found mainly in the _-bands.
Actin=I-band
Myosin=A-band
What are the 2 regulatory proteins inhibit the interaction of actin and myosin?
Troponin & Tropomyosin
Calcium binds with which regulatory molecule?
Troponin
Where does the aerobic pathway take place?
Mitochondria
Which pathway prefers to utilize creatine phosphate and glycogen?
Anaerobic pathway
What two benefits may the use of caffeine provide for athletes?
Burn fatty acids more efficiently (aerobic pathway)
Increase calcium permeability
Which type of anabolic steroid has fewer side effects but is detectable for a longer period of time?
Oil-based
What are some short term side effects of anabolic steroid use?
Headaches, dizziness, nausea, back-acne testicular atrophy increased aggressiveness gynecomastia tendon damage
What is the chemical composition of muscle?
75% water
20% protein
5% other
A single motor neuron and the group of muscle fibers which it supplies is known as the ___ __.
Motor unit
T/F: Precision type of activities contain motor units with fewer number of fibers.
True
Which neurotransmitter is released at the neuromuscular junction?
Acetylcholine (ACH)
Which enzyme recycles acetylcholine from the synaptic cleft?
Acetylcholinesterase (ACHe)
Which autoimmune disease destroys ACH receptor sites?
Myasthenia Gravis
T/F: Nicotine & snake venom both compete with ACH molecules and produce an action potential.
False: Nicotene can produce an action potential but snake venom cannot!
What do organophosphates inactivate leading to constant muscle contraction?
Acetylcholinesterase
T/F: Intrafusal muscle fibers have both afferent & efferent nerve fibers.
True
Extrafusal muscle fibers only have afferent or efferent nerves associated with them?
ONLY efferent
What do Golgi tendon organs detect?
Stretch of the tendon
What are Sharpey’s fibers?
Portions of collagen fibers of a tendon or ligament that penetrate into the bone giving a firm attachment site
What is an avulsion fracture?
When a fragment of bone is pulled out with the collagen fibers
Tendons have only ___ innervation.
Afferent; there is no motor function to tendons
Endurance muscles usually have which type of muscle fiber arrangement?
Pennate
Type II muscles generally are arranged in which fashion: pennate or parallel?
Parallel (aka Strap)
A muscle that produces the opposite effect from the agonist is known as the ___.
Antagonist
What is reciprocal innervation?
When a muscle contracts and the antagonist simultaneously relaxes
____ Phenomenon occurs in a newborn when both agonists and antagonists contract at the same time.
Co-Reflex Phenomenon
What 2 bones make up the shoulder girdle?
Scapula & Clavicle
What are the 3 unique facts about the clavicle?
- Undergoes both intramembranous and endochondral ossification.
- First bone to start ossifying (5th-6th wk of development)
- One of last to complete ossification (about 25 y.o.)
Where is the clavicle most frequently fractured?
First curvature
Which condition has abnormal ossification of the clavicle and skull bones, potentially even missing clavicles?
Cleidocranial dysostosis
How many ossification centers does the scapula have?
7; 1 primary and 6 secondary
__ ___ is when the acromion process fails to fuse with the rest of the bone.
Os Acromidae
What is Sprengel’s Deformity?
Undescended scapula due to it’s attachment to cervical vertebra.
The mammary glands are superficial to which muscles?
Pectoralis major
Serratus Anterior
What is the space where a small drop of milk can accumulate near the end of the lactiferous duct?
Lactiferous sinus
How many lobes are in each mammary gland?
15-20 lobes
__ & __ are hormones secreted by the ovaries and placenta.
Estrogen & Progesterone
Where is prolactin secreted from and what is it’s action?
Anterior pituitary; promotes milk production after birth
Where is oxytocin secreted from and what is it’s action?
Posterior pituitary; promotes the release of milk
What are the 1st secretions from the functional mammary gland?
Colostrum
Which contains the most immunoglobulins: colostrum, transitional milk, or mature milk?
Colostrum
When are inverted nipples concerning?
If it’s recent; could be indicative of carcinoma pulling on the ducts.
What is galactorrhea?
Secretions from the breast that is not associated w/ pregnancy or lactation
What is gynecomastia?
Enlargement and development of breast tissue in males; common in puberty
How many ossification centers does the humerus have?
8; 1 primary & 7 secondary
A humeral fracture at the surgical neck could injure which nerve?
Axillary nerve
A humeral fracture of the shaft could injure which nerve?
Radial nerve
What is the nerve supply to the pectoralis major?
Medial & Lateral Pectoral nerves
What muscles are absent in Poland’s Syndrome?
Pectoralis Major, Pectoralis Minor
also atrophy of mammary glands on that side, and absence of ribs
Where does the pectoralis minor insert?
Coracoid process of the scapula
T/F: Pectoralis major and minor have the same innervation.
False: Pec. major is Medial & Lateral Pectoral nerves
Pec. minor is MEDIAL Pectoral only!
Which roots help supply the subclavius muscle?
C5, C6
What is the anterior wall of the axilla formed by?
Pectoralis major
T/F: The posterior wall of the axilla is formed by the latissimus dorsi and the teres minor.
False…latissimus dorsi and teres MAJOR
The lower trunk of the brachial plexus is formed by the union of __ and __.
C8 & T1
Which roots help to make up the lateral cord?
C5, C6, C7
The cords of the brachial plexus are named to show their relationship to what?
The axillary artery
Which two nerves come directly off spinal nerves?
Dorsal Scapular,
Long Thoracic
What 3 muscles are supplied by the dorsal scapular nerve?
Rhomboid Major & Minor, Levator Scapulae
What is the serratus anterior supplied by?
Long Thoracic Nerve (C5, C6, C7)
Which nerve passes through the belly of the coracobrachialis muscle?
Musculocutaneous Nerve
Which nerve may give off the accessory phrenic nerve?
Nerve to Subclavius (C5, C6)
Which nerve continues into the forearm as the lateral antebrachial cutaneous nerve?
Musculocutaneous Nerve
What is the segmental innervation of the medial brachial cutaneous nerve?
T1 only
What is the only branch of the brachial plexus which is formed from more than one cord?
Median Nerve
Which nerve would supply the cutaneous region over the thumb?
Median Nerve
What is the motor supply from the upper subscapular nerve?
Subscapularis
The triceps brachii are supplied by which nerve?
Radial Nerve
The lateral side of the arm is which dermatome level?
C5
The skin of the palm is in which dermatome level?
C7
Which roots would contribute in a prefixed brachial plexus?
C4, C5, C6, C7, C8
T/F: Erb-Duchenne Palsy results from an injury to the upper roots of the brachial plexus.
True
How would an individual w/ Erb-Duchenne Palsy present?
Greatly disabled shoulder movements
Reasonably functional hand & digit movement
Loss of sensation on lateral aspect of arm & forearm
What is an injury to the lower roots of the brachial plexus called?
Klumpke’s Palsy
Which is more common: Erb-Duchenne or Klumpke?
Erb-Duchenne
What is Thoracic Outlet Syndrome?
Compression of cords of brachial plexus and axillary artery (both neurological and vascular problems)
- pain & paresthesia
- decr. skin temp and limb fatigue
What does the axillary artery continue as?
Brachial artery
What are the 6 specific branches of the axillary artery?
- Superior Thoracic
- Thoracoacromial
- Lateral Thoracic
- Subscapular
5 & 6. Anterior and Posterior Humeral Circumflex
Which of the following is not a branch of the thoracoacromial artery: acromial, scapular, pectoral, clavicular, or deltoid?
Scapular