Day 2

Question 1

What is the sarcoplasm?

Answer 1

It is the cytoplasm of a muscle cell

Question 2

What does the sarcoplasm contain?

Answer 2

Glycosomes and myoglobin

Question 3

What does a muscle cell contain?

Answer 3

Myofibrils, sarcoplasmic reticulum, and T tubules

Question 4

What are myofibril’s made up of?

Answer 4

Sarcomeres

Question 5

What are myofibrils?

Answer 5

They are rod like structures that run parallel to the length of the muscle fiber

Question 6

What are Sarcomeres?

Answer 6

They are the contractile units

Question 7

What is a Sarcomere composed of?

Answer 7

Myofilaments and contractile proteins

Question 8

What are the two types of microfilaments?

Answer 8

Thick( myosin) and Thin(actin)

Question 9

What are striations made out of?

Answer 9

A repeating series of dark, (A) bands and light( I) bands

Question 10

Where are stations found in?

Answer 10

They are evident along the length of each myofibril

Question 11

The A band has a lighter midsection called the what?

Answer 11

The H zone

Question 12

The H zone is bisected by the what

Answer 12

The M line

Question 13

The I band has a midline interruption called the what?

Answer 13

The Z disc

Question 14

A sarcomere is the region of what?

Answer 14

Of a myofibril between two successive Z discs

Question 15

What do thick filaments contain?

Answer 15

Bundled myosin molecules

Question 16

What does a myosin molecule consist of?

Answer 16

Six polypeptide chains with a rod like tail and globular heads attached via a flexible hinge

Question 17

What do Thin filaments contain?

Answer 17

Actin molecules

Question 18

What does Actin have?

Answer 18

Has a kidney shaped polypeptide sub units called globular Actin

Question 19

What does globular Actin have?

Answer 19

Myosin binding site

Question 20

G Acton, sub units polymerize Into what?

Answer 20

Long actin filaments called filamentous

Question 21

What do two intertwined F Actin filaments form?

Answer 21

Forms the backbone of each thin filament

Question 22

Thin filaments contain the regulatory proteins called what

Answer 22

Tropomyosin and troponin

Question 23

Elastic filaments are composed of what

Answer 23

Giant protein Titin

Question 24

Elastic filaments extends from what to what?

Answer 24

The Z disc to the thick filament

Question 25

What is the role of elastic filaments?

Answer 25

Maintains the organization of the A band

Question 26

What does dystrophin link?

Answer 26

The thin filament to the integral proteins of the sarcolemma

Question 27

Describe the sarcoplasmic reticulum

Answer 27

It is a smooth endoplasmic reticulum

Question 28

What does the sarcoplasmic rectum regulate?

Answer 28

Regulates the intercellular levels of ionic calcium

Question 29

What does the sarcoplasmic recticulum store?

Answer 29

It stores calcium

Question 30

When does the sarcoplasmic rectum release the calcium?

Answer 30

When the muscle fiber is stimulated to contract

Question 31

What are T tubules?

Answer 31

They are investigations of the sarcolemma that run deep into the cell between the terminal cisterns

Question 32

What does T tubules increase?

Answer 32

It increases the muscle fibers surface area

Question 33

What does T tubules allow?

Answer 33

It allows change in the membrane potential to rapidly penetrate deep into the muscle fiber

Question 34

What are triads?

Answer 34

They are groupings of three membrane structures

Question 35

Name the three membrane structures that make up a triad

Answer 35

Terminal cistern, T tubules, and terminal cistern

Question 36

What does contraction refer to in the sliding filament model?

Answer 36

It refers to the active shed of myosin cross bridges

Question 37

What are cross bridges?

Answer 37

Force generating sites

Question 38

What does the sliding filament model state during contraction?

Answer 38

It states that the thin filaments slide past the thick ones so that the Actin and myosin filaments overlap to a greater degree

Question 39

What occurs to the thick and the thin filaments during contraction of the sliding filament model?

Answer 39

Neither of them change Length during contraction

Question 40

Skeletal muscle contractions are what?

Answer 40

Voluntary

Question 41

What do skeletal muscle contractions require?

Answer 41

Requires activation of motor neurons in the spinal cord