Brainscape's Knowledge GenomeTM

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


See full index

PHYSIOLOGY > excitation and contraction > Flashcards

excitation and contraction Flashcards

1
Q

myofibril

A
  • longitudinally with in the muscle fibers
  • Z line
  • ACH in the neuromuscular junction releases CALCIUM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

sarcomeres

A
  • composed of this and thick filaments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

contraction

A
  • causes no change in A BAND

- shortening of I an H BAND

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

I BAND

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

H ZONE/BAND

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

A BAND

A
  • ACTIN and MYOSIN
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

ACH in the neuromuscular junction releases CALCIUM

CALCIUM descends into

A
  • T-tubule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

sarcolemma

A
  • covering of myofibril
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

sarcoplasmic reticulum

A
  • dumps calcium into the T-tubules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

T- tubules take calcium into the

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

ACTIN

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

MYOSIN

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

tropomyosin

A
  • covers the binding site
  • blocks the myosin head for attachment
  • prevents cross linking to actin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

calcium binds to

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

troponin

A
  • functions is to move tropomyosin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

hydrolysis of ATP causes

A
  • cross bridge to gain energy and affinity for actin

- loss of affinity for actin

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

SARCOPLASMIC RETICULUM

A
  • STORAGE SITE FOR CALCIUM
18
Q

2 ATP’s are needed

A
  • to start mechanical contraction
19
Q

ATP split are needed for

A
  • relaxation and contraction
20
Q

skeletal muscle action potential

A
  • SHORT

- causing multiple action potential

21
Q

complete TETANUS is obtained

A
  • when sufficient free calcium is available

- everything is engaged

22
Q

complete tetanus vs rigor mortis

A
  • tons of calcium , actin and myosin are engaged (TETANUS)
  • no ATP it doesn’t detached (RIGOR MORTIS)
  • SAME
23
Q

ABSOLUTE REFRACTORY PERIOD

A
  • is already depolarized
  • -70mV
  • happening
24
Q

relative refractory period

A
  • going back to normal
  • earliest time that can have a new stimulus
  • can get new depolarization
25
Q

preload

A
  • load on a muscle in a relaxed state prior to contraction
  • causes muscle to STRETCH
  • causes muscle to develop PASSIVE TENSION
26
Q

AFTERLOAD

A
  • how much effort to push to get the blood out 100lb

- the HIGHER THE BLOOD PRESSURE the MORE THE LOAD

27
Q 
drugs that decrease renin angiotensin aldosterone (CHF)
decrease AFTERLOAD (lowers amount of ischemia, arrhythmias, and death)
A
  • spironolactone
  • ACE inhibitors
  • beta blocker
  • ARB
28
Q

more preload

A
  • more passive tension
29
Q

stretch too much loose (DILATED CARDIOMYOPATHY)
over stretch the actin and myosin filaments
PASSIVE

A
  • FORCE
  • cannot generate force of contraction
  • causing low EF
30
Q

no stretch

A
  • straight contractility
31
Q

muscle contract when

A
  • they are moderately streched
32
Q

active

A
  • actin, myosin filaments are contracting

- consuming ATP

33
Q

passive, more stretch more passive

A
  • pulling muscles apart

- loosing active

34
Q

FORCE- VELOCITY CURVE

A
  • preload can go up
35
Q

Vmax is determined by

A
  • muscle ATPase activity
36
Q

maximum force generated

A
  • is determined by muscle mass
37
Q

white muscle

A
  • large
  • powerful muscles
  • utilized short term
  • LEG muscle of a sprinter, ocular muscles
  • large mass
  • high ATPase activity
  • high capacity for anaerobic glycolysis
  • low myoglobin
  • fast energy
38
Q

red muscle

A
  • smaller
  • less powerful muscle
  • utilized long term
  • for endurance
  • postural muscles
  • small mass
  • lower ATPase activity
  • slower
  • high capacity for aerobic metabolism
  • high myoglobin (red color) provide O2 to the cell
39
Q

skeletal muscle

A
  • striated (Z lines)
  • actin myosin form sarcomeres
  • sarcolemma lacks junctional complexes bet fibers
  • each fiber innervated
  • must be separately/ individually innervated
  • one muscle at a time
  • troponin to bind to calcium
    high ATPase activity
  • fast muscle
  • extensive sarcoplasmic reticulum inside the sarcomere
  • T-tubules form TRIADIC at A I junctions
  • lack Ca channels
40
Q

cardiac muscle

A
  • actin myosin form sarcomeres
  • striated (Z lines)
  • junctional complexes bet fibers including Gap junctions
  • electrical syncytium
  • troponin to bind to calcium (MI increase troponin)
  • intermediate ATPase activity
  • intermediate sarcoplasmic reticulum
  • T tubules form dyadic contact near Z lines
  • voltage gated calcium channels
  • plateau phase 200 msec
41
Q

smooth muscle

A
  • non striated (no Z lines, no sarcomeres)
  • actin myosin not organized into sarcomeres
  • gap junctions ( fast bidirectional)
  • electrical syncytium
  • detrusor, esophagus, diaphragm
  • calmodulin ( calcium modulation)to bind Ca2+
  • low ATPase activity
  • slow muscle
  • limited sarcoplasmic reticulum
  • lack T- tubules because their is a electrical syncytium to deliver electricity to the whole muscle simultaneously
  • sarcoplasmic reticulum controlled by 2nd messenger
  • voltage gated calcium channels

PHYSIOLOGY (40 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions