Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology > Lecture 5 - Skeletal Muscle Contraction > Flashcards

Lecture 5 - Skeletal Muscle Contraction Flashcards

1
Q

Myofilaments are compose of?

A

Actin and myosin filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Chains of sarcomeres are called?

A

Myofibirills

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Bundles of myofibrils are called?

A

Myofibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Bundles of myofibers are called?

A

Fascicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Muscles are made up of?

A

Multiple fascicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What surrounds myofibers?

A

Endomysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What surrounds fascicles?

A

Perimysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What surrounds muscles?

A

Epimysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Another word for sarcolemma?

A

Plasmolemma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Invaginations of the sarcolemma are called?

A

T-tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many T-tubules per sarcomere?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are T-tubules located?

A

Close to cisternae of the sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The sarcoplasmic reticulum sequesters what ion to be used as needed?

A

Ca2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do Z-lines do?

A

Anchor actin filaments

define individual sarcomeres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Composed entirely of actin

Shortens as muscle contracts

A

I band

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Composed entirely of myosin

Shortens as muscle contracts

A

H band

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Composed entirely of myosin

Does not shorten as muscle contracts

A

A band

18
Q

Step 1: Action potential arrives at terminal end of nerve fiber
THEN…

A

Step 2: Voltage gated calcium channels open; Ca2 influx into axon terminal

19
Q

Step 2: Voltage gated calcium channels open; Ca2 influx into axon terminal
THEN…

A

Step 4: Exocytosis of synaptic vesicles carrying Ach from axon terminal into synaptic cleft

20
Q

Step 4: Exocytosis of synaptic vesicles carrying Ach from axon terminal into synaptic cleft
THEN…

A

Step 5: Ach binds to Ach receptors on sarcolemma

21
Q

Step 5: Ach binds to Ach receptors on sarcolemma

THEN…

A

Step 6: Ligand-gated sodium channels open

22
Q

Step 6: Ligand-gated sodium channels open

THEN…

A

Step 7: Na+ ion influx

23
Q

Step 7: Na+ ion influx

WHICH CAUSES..

A

Step 8: End plate depolarization

24
Q

Step 8: End plate depolarization

THEN…

A

Step 9: Voltage gated sodium channels open

25
Q

Step 9: Voltage gated sodium channels open

WHICH LEADS TO…

A

Step 10: Sarcolemma action potential.

26
Q

Step 10: Sarcolemma action potential.

LEADS TO…

A

Step 11: Depolarization of T-tubules

27
Q

Step 11: Depolarization of T-tubules

WHICH CAUSES…

A

Step 12: A conformational change in DHP receptors

28
Q

Step 12: A conformational change in DHP receptors

WHICH CAUSES…

A

Step 13: Ryanodine receptor Ca2+ channels open

29
Q

Step 13: Ryanodine receptor Ca2+ channels open

THEN…

A

Step 14: Calcium release from Sarcoplasmic reticulum; increasing cytosolic concentration of Ca2+ to 10 micromoles/liter

30
Q

Step 14: Calcium release from Sarcoplasmic reticulum; increasing cytosolic concentration of Ca2+ to 10 micromoles/liter
THEN…

A

Step 15: Calcium binds to Troponin C, causing a conformational change

31
Q

Step 15: Calcium binds to Troponin C, causing a conformational change
WHICH MEANS…

A

Step 16: Active sites on actin filaments become exposed

32
Q

Step 16: Active sites on actin filaments become exposed

ALLOWING…

A

Step 17: Myosin heads bind to actin active sites

33
Q

DHP receptor location

A

T-Tubules

34
Q

Ryanodine receptor location

A

Sarcoplasmic reticulum

35
Q

Cytosolic calcium increases by a factor of

A

100

36
Q

SRCA?

A

Pumps calcium back into the cisternae after release from action potential

37
Q

After action potential, what happens to Ach?

A

acetylcholinesterase degrades Ach into choline and acetate

38
Q

what is meant by excitation-contraction (elctro-mechanical coupling)?

A

converting energies from action potential into mechanical energy in the sliding filament mechanism

39
Q

Metacholine
Carbachol
Nicotine

A

have same effect as Ach but not broken down by AchAse causing spasms

40
Q

Neostigme
Physostigmine
diisopropyl fluorophosphates

A

inactivate AchAse

41
Q

Curare

A

prevents passage of impulses from nerve ending into muscle (muscle relaxation)

42
Q

Myasthenia Gravis

A

autoimmune disease
antibodies attack AchAse
neostigmine can be used to inactiate AchAse

Physiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions