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Flashcards in Muscular System Deck (34)
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1
Q

What are the functions of muscles

A
movement
stability 
control of body openings and passages 
heat production 
glycemic control
2
Q

movement

A

move from place to place; move body contents

3
Q

stability

A

maintain posture

4
Q

control of body openings and passages

A

mouth; internal sphincters

5
Q

heat production

A

85% of body heat produced by skeletal muscles

6
Q

glycemic control

A

regulation of blood glucose concentration within its normal range; skeletal muscles absorb, store, and use a large share of
one’s glucose, and play a highly significant role in stabilizing it’s blood concentration

7
Q

what are the characteristics of muscles

A
responsiveness (excitability)
conductivity
contractility
extensibility
elasticity
8
Q

responsiveness (excitability)

A

when stimulated by chemical signals, stretch, and other stimuli, muscle cells respond with electrical changes across the cell membrane

9
Q

conductivity

A

stimulation of a muscle cell produces more than a local effect; the local electrical change triggers a wave of excitation that travels rapidly all the cell and initiates processes leading to contraction

10
Q

contractility

A

muscle cells are unique in their ability to shorten substantially When stimulated; enables them to create movement

11
Q

extensibility

A

ability to stretch again between contractions

12
Q

elasticity

A

ability to stretch, release, and recoil to a shorter length

13
Q

Epimysium

A

covers entire muscle; attachment to tendon

14
Q

perimysium

A

surrounds fascicle or bundle of skeletal muscle

15
Q

endomysium

A

surrounds individual skeletal muscle cell

16
Q

parallel

A

fibers run parallel and can be arranged with or without body/gaster (biceps brachii – with body/gaster); (rectus abdominis – without body/gaster)

17
Q

convergent

A

fibers meet at a common attachment site (mylohyoid)

18
Q

pennate

A

fibers arranged at an angle;

19
Q

unipennate

A

fibers on one side of tendon (extensor digitorum longus)

20
Q

bipennate

A

fibers on both sides of tendon (rectus femoris)

21
Q

multipennate

A

fibers branch within tendon (deltoid)

22
Q

circular

A

fibers arranged in circular pattern (orbicularis oris or oculi); sphincters

23
Q

tetanus (lock jaw)

A

caused by bacterium Clostridium tetani; toxins released cause the involuntary contraction of skeletal muscle; jaw muscles affected first

caused by a deep dirty wound

24
Q

botulism (food poisoning)

A

caused by bacterium Clostridium botulinum; toxins released prevent the release of Ach (acetylcholine); causes paralysis of respiratory muscles

treated with oxygen, acetylcholine and pump the stomach

25
Q

hernias

A

due to weakness in a muscle; organ can protrude through the muscle

26
Q

inguinal hernia

A

most common; groin region; small intestine pushes through groin muscles, and can twist and strangulate

27
Q

clostridium

A

doesn’t require oxygen

28
Q

hiatal hernia

A

most painful; weakness in diaphragm; stomach and liver push up into thoracic cavity; difficulty in breathing

29
Q

Muscular Dystrophy (MD)

A

group of genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles. Some forms of muscular dystrophy are seen in infancy, or childhood, while other forms may not appear until middle age or later.

30
Q

Duchenne’s Muscular Dystrophy

A

sex linked disease
females can be carriers
*is the most common form of MD
it primarily affects boys, since the recessive mutation in the p21 gene on the X chromosome; since males have one X they usually have the disease, whereas, females are carriers of the disease
the p21 gene codes for the protein dystrophin, which is involved with maintaining the integrity of the muscle; therefore, dystrophin is absent in people with Duchenne’s MD
onset is between 3 and 5 years, and progresses rapidly; most boys are unable to walk by age 12
**symptoms include: progressive difficulty walking; frequent falls; fatigue; and muscle deformities
diagnosis; a CPK test is performed to measure creatine phosphokinase to determine if the muscles are damaged; in Duchenne’s MD, CPK leaks out of the muscle cell and into the blood, so a higher level of CPK would confirm that the muscle is damaged
some boys die in infancy, while others have a pro-longed life span into adulthood; depending on the rate of progression of the disease
NO CURE

31
Q

Becker Muscular Dystrophy

A

**is a less severe form of Duchenne’s MD
have faulty or not enough dystrophin
onset is at about age 12 years; most men are unable to walk by age 25 to 30 years
***symptoms include: progressive muscle weakness of legs and pelvis; muscle weakness also occurs in arms, neck, and other areas of the body, but not as severely as in the lower half of the body; fatigue
diagnosis; CPK test

32
Q

Facioscapulohumeral Muscular Dystrophy:

A

**usually begins in the teenage years
**
progressive weakness in muscles of the face, arms, legs, and around the shoulders and chest
it progresses slowly, and can vary in symptoms from mild to disabling

33
Q

Myotonic Muscular Dystrophy:

A

**most common adult form MD
**symptoms include; prolonged muscle spasms; cataracts; cardiac disturbances; and endocrine disturbances
individuals with Myotonic MD have long, thin faces, drooping eyelids, and a swan-like neck

34
Q

Myasthenia Gravis:

A

“ grave muscle weakness “; progressive muscle weakness
**chronic, autoimmune neuromuscular disease
is caused by a defect in the transmission of nerve impulses to muscles
**antibodies block, alter, or destroy the receptors for acetylcholine at the neuromuscular junction; prevents muscle contraction from occurring
usually affects any skeletal muscles, and muscles that control eye and eyelid movement, facial expression, and swallowing
**occurs in both genders; most commonly affects young adult women (under 40 years), and older men (over 60 years), but can occur at any age
diagnosis with a blood test to measure presence of acetylcholine receptor antibodies
can use medications to help reduce and improve muscle weakness; acetylcholinesterase agents such as neostigmine, which help improve neuromuscular transmission, and increase muscle strength
patients can periodically go into remission and no symptoms occur