Muscles I

Question 1

Two types of regulatory proteins

Answer 1

Tropomyosin and troponin

Question 2

The fibre pennation angle of pennate muscles allow for …..

Answer 2

Packing of large numbers of fibres into smaller cross-sectional area

Question 3

Pennate fibres lie at _______ pennation angle

Answer 3

Oblique

Question 4

Pennation allows muscle fibres to be ______ relative to length of muscle

Answer 4

short

Question 5

Pennate muscles differ from fusiform muscles in that they contain (longer/shorter) fibres, possess (more/less) individual fibres, and exhibit (more/less) range of motion

Answer 5

Shorter fibres, more individual fibres, and less range of motion

Question 6

Perimysium surrounds?

Answer 6

A bundle of fibres called a fasciculus

Question 7

Differences in sarcomere_________ and ______ affect muscle’s force and power generating capacity

Answer 7

alignment and length

Question 8

Fusiform fibres run ______ to muscles long axis and _____ at tendinous attachment

Answer 8

parallel; taper

Question 9

Effect of training on muscle capiliaries

Answer 9

Increased capillary-to-muscle fibre ratio, enhanced capillary microcirculation

Question 10

Cross-bridge cycling depends on ____ _______

Answer 10

ATP hydrolysis

Question 11

______ actin filaments encircle each myosin filaments

Answer 11

Six

Question 12

Two types of contractile proteins

Answer 12

Myosin and actin

Question 13

Muscle functions (4)

Answer 13

Producing body movement, stabilizing body positions, storing and moving substances within the body, generating heat

Question 14

Contents of myofibrils

Answer 14

Myofilaments

Question 15

Low energy form of myosin head

Answer 15

ATP bound to myosin; low affinity for actin

Question 16

What stimulates capillary development during training?

Answer 16

Vascular stretch/shear stress on vessel walls from increased blood flow

Question 17

Contents of muscle fibre

Answer 17

Myofibrils

Question 18

Muscle properties (3)

Answer 18

Excitable, contractable, extensible

Question 19

Sarcoplasmic reticulum provides

Answer 19

Structural integrity

Question 20

Sarcolemma surrounds…

Answer 20

Each muscle fibre and encloses a fibre’s cellular contents

Question 21

Three types of muscle proteins

Answer 21

1. Contractile
2. Regulatory
3. Structural

Question 22

___________: shortening of muscles; how muscles generate force

Answer 22

Cross-bridge cycle

Question 23

________ muscles facilitate rapid muscle shortening because fibre length = muscle length

Answer 23

Fusiform

Question 24

High energy form of myosin head

Answer 24

ADP and Pi bound; high affinity for actin

Question 25

________ filaments have two twisted monomer chains bound by tropomyosin polypeptide chains

Answer 25

Actin

Question 26

________________: how muscle contractions are turned on and off

Answer 26

Excitation-contraction coupling

Question 27

Purpose of structural proteins

Answer 27

Contribute to the alignment, stability, extensibility, and elasticity

Question 28

Five types of structural proteins

Answer 28

1. titin
2. alpha-actinin
3. myomesin
4. nebulin
5. dystrophin

Question 29

Two main mechanisms of force generation in muscle

Answer 29

1. crossbridge cycle

2. excitation-contraction coupling

Question 30

Pennate muscles generate _______ power

Answer 30

Considerable

Question 31

Endomysium surrounds…?

Answer 31

Each muscle fibre to separate it from neighbouring fibres

Question 32

Degree of pennation directly impacts….

Answer 32

Sarcomere fibre number per cross-section of muscle

Question 33

Epimysium surrounds…?

Answer 33

Entire muscle and blends into intramuscular tissue sheaths to form tendons

Question 34

_________ filaments are bundles of molecules with polypeptide tails and globular heads

Answer 34

Myosin

Question 35

Myofilaments consist of:

Answer 35

Actin and myosin

Question 36

Four major steps of contraction cycle

Answer 36

1. ATP hydrolysis
2. Attachment of myosin to actin
3. Power stroke
4. Detachment of myosin from actin