The Muscular System

Question 1

The three muscle tissues types

Answer 1

Skeletal, smooth, cardiac

Question 2

Skeletal Muscle

Answer 2

Voluntary control, striated appearance.
Attached to bones and is responsible for voluntary movements.

Question 3

Cardiac Muscle

Answer 3

Involuntary control, striated but with intercalated discs.
Found in the heart, responsible for pumping blood.

Question 4

Smooth Muscle

Answer 4

Involuntary control, non-striated.
Found in walls of organs and vessels, responsible for involuntary movements like digestion.

Question 5

Sarcomere

Answer 5

the fundamental unit of muscle that’s responsible for contraction.

Question 6

Z-discs

Answer 6

Boundary of the sarcomere; anchor thin filaments.

Question 7

I band

Answer 7

Region with only thin filaments; shortens during contraction.

Question 8

A band

Answer 8

Region containing the entire length of thick filaments; remains unchanged during contraction.

Question 9

H zone

Answer 9

Central region of A band with only thick filaments; shortens during contraction.

Question 10

M line

Answer 10

Middle of the sarcomere; stabilizes thick filaments

Question 11

Thin Filaments

Answer 11

made of actin

Question 12

Actin

Answer 12

Actin is the protein that forms the thin filaments and provides the binding sites for myosin during muscle contraction.

Question 13

Tropomyosin

Answer 13

Tropomyosin is a protein that covers actin’s myosin-binding sites, preventing contraction until activated.

Question 14

Troponin

Answer 14

Troponin is a protein that binds calcium ions, causing tropomyosin to move and expose actin’s binding sites for myosin.

Question 15

Thick filaments

Answer 15

Made of myosin

Question 16

Myosin

Answer 16

Structured with a head, neck and tail. Binds to actin and uses ATP to pull actin filaments toward the center of the sarcomere and contract the muscle

Question 17

ATP

Answer 17

adenosine triphosphate; energy!!!!!

Question 18

CA2++

Answer 18

calcium

Question 19

Role of calcium

Answer 19

binds to troponin, allowing myosin to bind actin and begin the contraction process

Question 20

Neuromuscular Junction (NMJ)

Answer 20

a specialized synapse (a structure that allows a neuron to pass a signal to another neuron) that allows the nervous system to transmit electrical impulses to muscles, causing them to contract

Question 21

Lever

Answer 21

a rigid bar that rotates around a fixed point (the fulcrum).

Question 22

Levers in the body

Answer 22

the bones act as levers, the joints serve as fulcrums, and muscles provide the force to move the bones.

Question 23

3 types of levers in the body

Answer 23

first class, second class, third class

Question 24

First-class lever

Answer 24

Fulcrum in the middle (e.g., neck movement).

Question 25

Second-class lever

Answer 25

Resistance in the middle (e.g., standing on tiptoes).

Question 26

Third-class lever

Answer 26

Effort in the middle (e.g., bending the arm).

Question 27

Origin Point

Answer 27

The attachment site of the muscle on the bone that remains still during contraction.
Example: The biceps brachii muscle originates at the scapula.

Question 28

Insertion Point

Answer 28

The point where the muscle attaches to the bone that moves during contraction.
Example: The insertion of the biceps is at the radius.

Question 29

Action

Answer 29

The specific movement that the muscle causes when it contracts.
Example: The action of the biceps is flexion of the elbow joint.

Question 30

Prime Mover (Agonist)

Answer 30

The muscle primarily responsible for a specific movement.
Example: The biceps brachii is the prime mover during elbow flexion.

Question 31

Synergist

Answer 31

Muscles that assist the prime mover in creating a movement.
Example: The brachialis muscle assists the biceps in elbow flexion.