Chapter 17

Question 1

Muscles 3 general functiond

Answer 1

Enables the body and its parts to move

Heat prodcution

Posture

Question 2

3 functional characteristics of skeletal muscle

Answer 2

Excitability
Contractility
Extensibility

Question 3

Excitability meaning

Answer 3

Ability to be stimulated

Question 4

Contractility meaning

Answer 4

Ability to contract/ shorten movement

Question 5

Extensibility meaning

Answer 5

Ability to extend/ stretch, allowing muscle to return to their resting length

Question 6

THREE TYPES OF MUSCLE TISSUE

Answer 6

Skeletal
Cardiac
Smooth

Question 7

Skeletal muscle is also called _____ or ______

Answer 7

Striated or voluntary

Question 8

Skeletal muscle represents ____ to______ of body weight

Answer 8

40-50%

Question 9

Skeletal muscle is attached to ____

Answer 9

Bones

Question 10

Skeletal muscle has _________ striations and __________ contractions

Answer 10

Microscopic striations

Voluntary contractions

Question 11

Skeletal muscle has ____________ cell/fiber that are arranged ________

Answer 11

Multinucleated

Around periphery of cell

Question 12

Skeletal muscle cells are called

Answer 12

Fibres

Question 13

Plasma membrane of muscle cell is called

Answer 13

Sarcolemma

Question 14

Cytoplasm of skeletal muscle cell called

Answer 14

Sarcoplasm

Question 15

The endoplasmic reticullum of the skeleton muscle is called ______ and the membrane is responsibe for ________

Answer 15

SarcOPLASMIC reticulum (SR)

Responsible for calciuam release and storage

Question 16

Muscle fibres contain many _____ , ______, _______ and have inward extensions of the sarcolemma called _____

Answer 16

Mitochondria, nuclei, myofibrils,

T-tubules

Question 17

What are myofibrils

Answer 17

Numerous fine fibres packed together in the sarcoplasm

Question 18

What do t-tubules allow?

Answer 18

Allow nerve impulses to move deeper into the fibre

Question 19

Myofibrils are made up of very fine thread like structures called

Answer 19

Myofilaments

Question 20

_____ types of proteins make up myofilaments

Answer 20

4

Question 21

2 main types of proteins that make up the myofilaments

Answer 21

Myosin

Actin

Question 22

Myosin makes up most of the ______ myofilaments

Answer 22

Thick

Question 23

Actin makes up most of the _______ myofilaments

Answer 23

Thin

Question 24

Actin and myosin are arranged in repeating segments called

Answer 24

Sarcomere

Question 25

A sarcomere is the basic functional unit of _____

Answer 25

Muscle fibres

Question 26

Individual sarcomeres are seperated by

Answer 26

Z-lines (Z disks)

Question 27

A skeletal muscle fibre will stay at rest until

Answer 27

It is stimulated by a nerve impulse which arrived via a motor neurons

Question 28

The nerve impulse travels along the motor neuron until it reaches the

Answer 28

Neuromuscular junctino

Question 29

A synapse is

Answer 29

Microscopic gap between the end of motor nueon and sarcolemma of the fibre

Question 30

To transmit the nerve impulse across the synapse, what must be released

Answer 30

Nuerotrainsmitter

Question 31

Where do neuro transmitters bind when they are released

Answer 31

The muscle fibres sarcolemma

Question 32

What is the result of nuerotransmitters binding to the sarcolemma?

Answer 32

Excitation of sarcolemma, sending a nerve impulse resulting in calcium ions to be released into the sarcoplasm

Question 33

4 Steps of muscle movement

Answer 33

1. Each myosin head in the thick filament moves into a resting position after an ATP molecule binds and transfers its energy 2. Calcium ions released from the sercoplasmic reticulum bind to troponin in the thin filament thereby allowing tropomysin to shift from its position blocking the active sites of actin molecules 3. Each myosin head then binds to an active site on thin filaments and displaces the remnants of ATP hydrolysis- ADP & Pi 4. The release of stored energy from step q provides the force needed for each head to move back to its original position and pull actin along with it. Each head will remain bound to actin until another ATP molecule binds to it and pulls it back into its resting position.

Question 34

During contraction, _____ binds to actin forming _______ which acts as levers to pull the ______ past eachother

Answer 34

Myosin Cross bridges Myofilaments

Question 35

As muscle contracts, _________ slide past each other

Answer 35

Myofilaments

Question 36

Contraction requires _______ (for cross bridge formation) and _____

Answer 36

calcium Atp

Question 37

SR actively removes _____ to stop contraction

Answer 37

Calcium

Question 38

Whole blood is

Answer 38

55% plasma 45% formed elements Seperated by buffy coat