Week 5 Muscles 1

Question 1

What are the myofilaments?

Answer 1

Thin actin filaments and thick filaments of myosin

Question 2

Movement is achieved by?

Answer 2

Contraction of myofilaments

Question 3

Muscle responsibility

Answer 3

Movement of body parts

Question 4

Do all of our cells have actin and myosin?

Answer 4

Yes. It’s only a matter of how they organize and assemble it in the cytoplasm. Most HIGHLY characterized in muscle

Question 5

Types of muscle

Answer 5

1) Striated

2) Smooth

Question 6

Examples of striated muscle?

Answer 6

1) Skeletal
2) Visceral striated muscle
3) Cardiac

Question 7

Examples of special visceral striated muscle?

Answer 7

Tongue, pharynx, upper part of esophagus

Question 8

What is the biggest way to differentiate smooth and striated muscle?

Answer 8

Smooth muscle doesn’t have striations

Question 9

What are the myofilaments?

Answer 9

Actin and myosin

Question 10

What is myofibril?

Answer 10

The muscle fiber that makes up tissue; made of myofilaments (actin and myosin)

Question 11

Myofibrils are formed from?

Answer 11

Myoblast precursors, it’s a fusion of cells, so it is multinucleated

Question 12

Myofibrils are multinucleated or singular?

Answer 12

Multinucleated bc of the fusion of myoblast precursors

Question 13

Myofibrils bundle together to form a?

Answer 13

Muscle fiber

Question 14

Muscle fibers are different form what other fibers? How?

Answer 14

ECM fibers. ECM are individual proteins. Muscle fibers are fused multinucleated long cells

Question 15

Skeletal muscle is many muscle fibers held together by?

Answer 15

Connective tissue: Endomysium, perimysium, epimysium

Question 16

Endomysium?

Answer 16

Delicate reticular fibers surrounding individual muscle fibers

Question 17

Perimysium?

Answer 17

Thicker connective tissue surrounding groups of fibers to form a bundle or fascicle

Question 18

Epimysium? What is found here?

Answer 18

Sheath of dense connective tissue surrounding the collection of fascicles. MAJOR vascular and nerve supply are found here

Question 19

What is a muscle fascicle?

Answer 19

A bundle of muscle fibers grouped together by perimysium

Question 20

List fascicle, myofibril, actin/myosin, and fiber in order

Answer 20

actin/myosin < myofibril < muscle fiber < muscle fascicle

Question 21

What connective tissue surrounds fascicle, myofibril, and fiber?

Answer 21

Endomysium (myofibril) < Perimysium (fiber)

Question 22

All muscles end with what connective tissue?

Answer 22

Tendons

Question 23

What are the 3 types of skeletal muscle fibers?

Answer 23

1) Type 1 (slow oxidative)
2) Type 2a (fast oxidatiove glycolytic fibers)
3) Type 2b (fast glycolytic fibers)

Question 24

Type 1 striated skeletal muscle?

Answer 24

slow oxidative small fibers, RED, high myoglobin content, SLOW TWITCH, fatigue resistant

Question 25

Type 2a striated skeletal muscle

Answer 25

*fast oxidative glycolytic fibers*Intermediate fibers- pink, many mitochondria, high myoglobin contant, FAST TWITCH FATIGUE RESISTANT, generate HIGH peaks of muscle tension

Question 26

Type 2b striated skeletal muscle

Answer 26

*fast glycolytic fibers*, large and light color, less myoglobin and few mitchodondria, FAST TWITCH FATIGUE PRONE fibers, generate high muscle tension in short bursts

Question 27

What type of striated skeletal muscle has HIGH mitochondria?

Answer 27

Type 2a

Question 28

What type of striated skeletal muscle generate high tension?

Answer 28

Type 2a and Type 2b (more)

Question 29

What type of striated skeletal muscle is slow twitch?

Answer 29

Type 1

Question 30

What type of striated skeletal muscle is fast glycolytic fibers, slow oxidative, & fast oxidative glycolytic fibers?

Answer 30

Slow oxidative= Type 1 fast oxidative glycolytic fibers=Type 2a fast glycolytic fibers=Type 2b

Question 31

What type of striated skeletal muscle have high myoglobin?

Answer 31

Type 1 and Type 2a

Question 32

What type of striated skeletal muscle generated the highest amount of muscle tension?

Answer 32

Type 2b