Brainscape's Knowledge GenomeTM

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


See full index

anatomy exam iii > Muscles and Muscle tissue > Flashcards

Muscles and Muscle tissue Flashcards

1
Q

Muscle tissue transforms ___ energy into ____ energy

A

chemical energy (ATP) into directed mechanical energy

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

What are the 3 types of muscle tissue in the body?

A

Skeletal, cardiac, and smooth.

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

Which muscle tissue is striated?

A

Skeletal and cardiac

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

What is the function of cardiac tissue?

A

it contracts at a steady rate due to the heart’s own pacemaker

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

What is the function of smooth tissue?

A

Smooth muscle forces fluids and other substances through internal body channels, forms valves, and dilates/constricts.

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

What is the function of skeletal tissue?

A

subject to unconscious movement, helps support movement, contracts rapidly

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

What types of muscle tissue are involuntary?

A

Cardiac and smooth

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

What types of muscle tissue are voluntary?

A

Skeletal

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

List and define the 4 characteristics common to ALL types of muscle tissue.

A

Excitability (responsiveness): ability to receive/respond to stimuli by changing its membrane potential

Contractility: ability to forcibly shorten when stimulated

Extensibility: ability to stretch or extend – even beyond resting length

Elasticity: ability to recoil to resting length

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

List and define the 4 functions of muscle tissue.

A

**Produce Movement: **
locomotion and manipulation
contraction of the heart
blood vessel dilation/constriction
movement of all fluids/substances through tracts

**Maintain posture and body position **

**Stabilize joints **

**Generate heat **

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

In order to contract, skeletal muscles require __________,________, and _________.

A

huge amounts of oxygen, nutrients, and quick waste removal.

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

Equation for cellular respiration

A

C6H12O6 + 6O2 –> 6CO2 + 6H2O + ATP

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

Where does O2 come from? How about C6H12O6?

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

What happens to the CO2 and H20 created?

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

Define epimysium, perimysium, and endomysium. What type of structures are they? Know what each covers. What does these structures join together to become?

A

They are all connective tissue sheaths.

Epimysium: most external; dense irregular connective tissue surrounding the entire muscle; may blend with fascia

Perimysium: fibrous connective tissue surrounding fascicles (groups of muscle fibers)

Endomysium: most internal; fine areolar connective tissue surrounding each muscle fiber

Connective tissue sheaths become the tendons that join muscles to bones

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

Origin

A

the immovable bone or less movable bone

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

Insertion

A

the more movable bone

The biceps muscle, which originates from the scapula and inserts into th

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

A tendon is an example of what type of attachment?

A

insertion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the other type of attachment? Name a muscle that attaches this way.

A

Direct (Fleshy): epimysium fused to periosteum or perichondrium

Indirect: connective tissue wrappings extend beyond muscle as ropelike tendon or sheetlike aponeurosis (more common!)

20
Q

What shape is a muscle cell? What are two cellular organelles that a muscle cell would have multiple of?

A

Skeletal muscle fibers are long, cylindrical cells; contain multiple nuclei. Muscle cells would have a mitochondria and a nuclei.

21
Q

Define Sarcolemma

A

its the plasma membrane of a cell fiber

22
Q

Define sarcoplasm

A

its the cytoplasm of a muscle fiber

23
Q

What are glycosomes?

A

granules of stored glycogen

24
Q

Define myoglobin.

A

a red pigment that stores oxygen

25
Q

What are myofibrils? How many might you find in a single muscle cell?

A

They are densely packed, rod like elements. A single muscle fiber can contain 1000 of myofibrils.

26
Q

Myofibrils are chains of

A

Sarcomeres

27
Q

What bands make up dark region of sarcomere? Light region?

A

The A bands make up the dark regions. (H zone and M line)

The I bands make up the lighter regions. (Z disc/line)

28
Q

Why is the H Zone a lighter region within the dark region?

A

the H zone is lighter because within the H zone only myosin and no actin fibers are present block the passage of light; the center of each H zone is marked by a darker M line.

29
Q

Is actin the thin filament or the thick filament? What about myosin?

A

Actin is the thin filament and myosin is the thick filament.

30
Q

What are polypeptide chains? What types of polypeptide chains make up the thick filament? Within the thick filament, where can you find each type of polypeptide chain?

A

Thick filaments are composed of myosin. Each myosin molecule contains 2 heavy and 4 light polypeptide chains. Heavy chains intertwin to form myosin tail. Light chains form globular myosin heads.

31
Q

What is the function of the myosin head?

A

myosin heads link thick and thin filaments during contraction to form cross bridges

32
Q

Define G (Globular) Actin. What is its function?

A

Actin has kidney shaped, polypeptide subunits called G (Globular) actin. G actin subunits bear the sites for myosin head attachment during cross bridge formation. G actin subunits link together to form long, fibrous F actin

33
Q

Define F (Fibrous) Actin. What is its function?

A

When G actin subunits link together, F actin is formed. 2 F actin strands twist together to form a thin filament.

34
Q

List the 2 regulatory proteins bound to actin. What is each of their specific functions?

A

Tropomyosin and Troponin. They are two regulatory proteins bound to actin to control muscle contraction. Tropomyosin is a rod shaped protein that spirals around the actin core and blocks myosin-binding sites. Troponin is a globular protein, which is able to bind 1-actin, 2-tropomyosin, 3-calcium.

35
Q

What role does the protein elastin play? How about dystrophin?

A

Elastic filament is composed of protein titin, it holds thick filaments in place, helps to resist excessive stretch, and assists with recoil.

Dystrophin is a structural protein that links the thin filaments to the integral proteins of the sarcolemma.

36
Q

Broadly, what are the muscular dystrophies?

A

muscle-destroying diseases that generally appear during childhood.

37
Q

What are some specific symptoms of Duchenne Muscular Dystrophy (DMD)? What protein is impaired in DMD? What does impairment of this protein cause in terms of muscle function? Do you remember how scientists are attempting to cure DMD? I talked about it in class!

A

It is a inherited sex-linked recessive disease. It is almost exclusively seen in males. It typically ocurrs between the ages of 2-7. The earliest symptoms are clumsiness, and frequent falls. Caused by defective gene for dystrophin – a protein that links thin filaments to extracellular matrix and stabilizes sarcolemma. In those with DMD, the sarcolemma can tear easily allowing entry of excess calcium
Excesses of calcium damage contractile fibers and cause inflammation
Regenerative capacity is lost resulting in increased apoptosis of muscle cells and loss of overall muscle mass

38
Q

What is sarcoplasmic reticulum? What is its function?

A

it is a netword of smooth ER tubules surrounding each myofibril. It functions in regulation of intracellular calcium levels by storing and releasing calcium on demand.

39
Q

What is a terminal cistern? Where can you find them?

A

SR tubules that form perpendicular cross channels at the A-I band junction; always occur in pairs. You can find them in the sarcoplasmic reticulum.

40
Q

What is a T-Tubule? Where can you find them? What is its function?

A

T-tubule is a tube formed by the protrusion of the sarcolemma deep into the cell’s interior - pass by 1 myofibril to the next. It occurs at the A-I band junction in the sarcolemma. T Tubules allow electrical nerve transmissions to reach deep into the interior of each muscle fiber and trigger the release of calcium, and T-tubule lumen greatly increase the muscle fiber’s surface area.

41
Q

.Together, the 2 terminal cisterns and the T-Tubule are known as the __________?

A

triad

42
Q

Protruding proteins from the T-Tubules act as what type of sensors?

A

voltage sensors- change shape in response to an electrical current

43
Q

Protruding proteins from the SR act as what type of sensors?

A

they form gated channels through which calcium can be released

44
Q

What happens when an electrical impulse passes through the triad?

A

When an electrical impulse passes by, T Tubule proteins change shape, SR proteins change shape, and calcium is released into the cytoplasm.

45
Q
  • Contraction is generation of ___________ by activation of myosin’s _____________________.
A

generation of force, by the activation of myosin’s cross bridges.

46
Q
  • Which myofilament slides in the sliding filament model? Do actin and myosin change their individual lengths? If not, how does the sarcomere change length?
A

In a relaxed state, thin and thick filaments overlap only slightly at the ends of the A band
During contraction, thin filaments slide past thick filaments – actin and myosin overlap more
Actin and myosin do not change their lengths
When the nervous system stimulates a muscle fiber, myosin heads are allowed to bind to actin, cross bridges are formed, and the sliding process begins

anatomy exam iii (5 decks)

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