A&P - Chapter 17 (Part 1)

Question 1

What do muscles contribute to?

Answer 1

The body’s framework/shape and functions

Question 2

What are 3 general functions muscles help with?

Answer 2

1. Movement
2. Heat production
3. Posture

Question 3

What are 3 functional characteristics of skeletal muscle tissues?

Answer 3

1. Excitability
2. Contractility
3. Extensibility

Question 4

Excitability

Answer 4

Ability to be stimulated

Question 5

Contractility

Answer 5

Ability to contract/shorted

- movement

Question 6

Extensibility

Answer 6

Ability to extend/stretch, allow muscles to return to their resting length

Question 7

What are 3 types of muscle tissues?

Answer 7

1. Skeletal
2. Cardiac
3. Smooth

Question 8

What are 2 other names for skeletal muscle?

Answer 8

1. Striated

2. Voluntary

Question 9

What % do skeletal muscles represent in weight?

Answer 9

40-50%

Question 10

Where are skeletal muscles attached to?

Answer 10

Bones

Question 11

What appear on skeletal muscles?

Answer 11

Multi-nucleated cells/fibre

- arranged around periphery of cell

Question 12

Another word for muscle cells?

Answer 12

Muscle fibres

- threadlike appearance

Question 13

Sarcoplasmic reticulum

Answer 13

Membrane that is responsible for Ca release and storage

Question 14

What do muscle fibres contain? (4)

Answer 14

1. Many mitochondria
2. Several nuclei
3. Myofibrils
4. T-tubules

Question 15

Myofibrils

Answer 15

Numerous fine fibres packed close together in the sarcoplasm

Question 16

T-tubules

Answer 16

Inward extensions of the sarcolemma that allow nerve impulses to move deeper into the fibre

Question 17

What are myofibrils made up of?

Answer 17

Myofilaments

Question 18

Myofilaments

Answer 18

Very fine, threadlike structures

Question 19

What makes up myofilaments?

Answer 19

4 types of proteins

• 2 myosin
• 2 actin

Question 20

What protein makes up the thick myofilaments?

Answer 20

Myosin

Question 21

What proteins make up the thin myofilaments?

Answer 21

Actin

Question 22

Sarcomeres

Answer 22

Myofilaments (actin and myosin) are arranged in repeating segments

Question 23

What is a sarcomere?

Answer 23

Is the basic functional (contractile) unit of muscle fibres

Question 24

What are individual sarcomeres separated by?

Answer 24

Z-line

- Z-disks

Question 25

When will a skeletal muscle no longer be in the rest position?

Answer 25

When it gets stimulated by a nerve pulse

Question 26

How does a nerve pulse arrive to the muscle?

Answer 26

Through a motor neuron

Question 27

When does the motor neuron stop its impulse movement?

Answer 27

When is reaches the neuromuscular junction

- synapse

Question 28

Synapse

Answer 28

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