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Flashcards in Muscle lecture notes Deck (67):
1

What does muscle mean?

Little mouse

2

Functions of muscle

*Movement of bones
*Movement of fluids
*Constriction/dilation of tubes
*Heat generators

3

Muscles can only...

Contract, shorten in length, and pull

4

Muscles can NOT...

Push

5

Name the 3 body movements

1) Prime movers (action)
2) Antagonists (opposite of prime movers)
3) Synergists (work with prime movers)

6

Examples of the 3 body movements when we flex the forearm

1) Prime mover- biceps brachii
2) Antagonists- triceps brachii
3) Synergists- brachialis

7

How do we "push" if muscles only pull?

By levers for example olecranon process

8

What kind of tissue are tendons?

Dense regular connective tissue, they attach muscle to bone or another muscle

9

Aponeurosis are

Tendons that form thin, tough flattened sheets

10

Origin is an

Attachment that is more proximal or more stationary

11

Insertion is an

Attachment that is more distal or more mobile

12

Belly is

Body, main region that shortens & thickens when it contracts. Creates the action

13

What are the different muscle shapes

1) Circular muscles
2) Parallel muscles
3) Convergent muscles
4) Pennate muscles

14

The fascicles in a parallel muscle

Run parallel to its long axis. They run side by side

15

The fibers in a pennate muscle

Are arranged at an oblique angle to the tendon. The fibers come off the sides of the tendon.

16

What are the different types of pennate muscles

1) Unipennate: All muscle fibers on the same side of the tendon
2) Bipennate: Muscle fibers on both sides of the tendon
3) Multipennate: Tendon branches within the muscle

17

Name example for Unipennate, bipennate, & multipennate muscles

1) Unipennate: Extensor digitorum
2) Bipennate: Rectus femoris
3) Multipennate: Deltoid

18

Convergent fibers are

Over a wide area but come together in a common tendon (pectoralis major)

19

Circular muscle fibers are

The sphincter fibers are concentric around a body opening (orbicularis oris)

20

Name the types of muscle

1) Skeletal
2) Cardiac
3) Smooth

21

Smooth muscles are

Muscles of the organs and blood vessels. Unicleate, tapered ends, non-striated, involuntary

22

Cardia muscle is

The heart muscle. 1-2 nuclei, branched, intercalated discs, striated, involuntary

23

Skeletal muscle is

Muscles attached to the bones, multinucleate, peripheral nuclei, striated, voluntary

24

Myology=

Study of muslces

25

Muscle comes from

Mesoderm

26

Some mesoderm differentiate into

Somites which in turn differentiate into myotomes

27

How does a muscle come about?

Mesoderm>Somite>Myotome>Muscle

28

Myotomes form

Skeletal muscles

29

Epimysium surrounds

The entire muscle

30

Perimysium surrounds

Bundles (fascicles)

31

Endomysium surrounds

Muscle fiber. Satellite cells are scattered here & there

32

Satellite cells help repair

Tissue damage

33

Sarcomere is a

Contractile unit

34

Sarco means

Flesh

35

Sarcophage is a

Flesh eater

36

Sarcophagidae flies eat

Flesh, or at least their maggots do

37

The plasma membrane in a muscle cell is

Sarcolemma

38

The transverse (T) tubules are

Deep, tubular extensions of the sarcolemma

39

The ER endoplasmic reticulum in a muscle cell is

Sarcoplasmic reticulum (SR)

40

The "canal" ends of SR are

Terminal cisternae

41

One T tubule plus 2 lateral terminal cisternae=

Triad

42

What are important for the conduction of impulse to stimulate muscle contraction?

*Sarcolemma
*Transverse (T) tubules
*Sarcoplasmic reticulum (SR)
*Terminal cisternae
*Triad

43

T-tubules carry

Nerve impulses from the surface sarcolemma deep into the sarcoplasm.

44

Terminal cisternae are

Smooth ER: Stores Ca++ until released when a nerve impulse arrives

45

Neuron impulse travels to the muscle cell membrane=

Neuromuscular junction (motor end plate or synaptic knob)

46

Synaptic vesicles contain

Acetylcholine (ACh)

47

When a nerve impulse reaches the motor end plate what happens?

It releases Ach which crosses the synaptic cleft & binds to Ach receptors on the sarcolemma

48

The action potential (nerve impulse) continues (now on the muscle cell) across the entire sarcolemma and...

Down the triads

49

What releases stored Ca++ onto the muscle proteins?

Sarcoplasmic reticulum

50

Muscle proteins are called?

Myofilaments

51

What are the two types of muscle proteins myofilaments?

Thick and thin.
1) Myosin- thick filaments. A swivel headed protein chain.
2) Actin tropomyosin troponin (proteins)- thin filaments. Double strands of actin plus strands of tropomyosin that cover the active binding sites on each actin

52

Troponin protein holds what in place?

Tropomyosin

53

What are the different banding patterns?

A bands
I bands
Z line
H zone

54

A bands are

(dark) includes H zone, M
line & zone of (thin & thick filament) overlap

55

I bands are

(light); the region between the A band
& Z line containing primarily thin filaments

56

Z line functions as

The connecting framework for the thin filaments and defines the borders of the sarcomere (from Z line to Z line)

57

The H zone

or H band, is also lighter since it has thick filaments only & the M line running down the center

58

Banding: “dark” has an “A” in the word, Thus “A” band is....

Dark

59

Banding: “light” has an “I” in the word, Thus “I” band is

Light

60

Banding: “Z” is at the end of the alphabet
Thus “Z” marks the...

End of the sacromere

61

Banding: “H” and “M” are in the middle of the alphabet, thus

They are in the middle of the sacromere

62

The current model for muscle contraction is called?

Sliding filament theory

63

In relaxed muscle tropomyosin blocks the...

actin binding sites, preventing myosin cross-bridges

64

When Ca++ is released, it binds to troponin causing it to...

Shift the position of tropomyosin, opening actin binding sites for myosin heads to form cross-bridges

65

Cross bridge results in a power stroke due to potential energy stored in the myosin head. ATP energy is required to...

Detach the cross-bridge and reload the head

66

Acetylcholinesterase (AChE) In the synaptic cleft breaks down...

ACh. The action potential ceases

67

The sarcoplasmic reticulum reabsorbs

Ca++ via active transport