Muscular System

Question 1

Function of muscular system

Answer 1

Enables body to move by the ability of muscles cells to contract

Question 2

Skeletal muscle

Answer 2

Composed of skeletal muscle and connective tissue. Extend from one bone across a joint to another bone

Question 3

Origin

Answer 3

Attached to the bone that remains relatively stationary when movement occurs

Question 4

Insertion

Answer 4

Point of attachment to the bone that moves when a muscle contracts

Question 5

Body

Answer 5

Main part of the muscle

Question 6

Tendons

Answer 6

Strong cords of fibrous connective tissue. Muscles attach to bone by tendons

Question 7

Bursae

Answer 7

Small synovial lined saves containing small amount of synovial fluid. Between tendons and underlying bone

Question 8

Thick myofilaments

Answer 8

Contain protein myosin. Myosin heads attach to actin and pull them toward middle of sacromere. Creating contraction

Question 9

Thin myofilaments

Answer 9

Composed of actin.

Question 10

Sacromere

Answer 10

Basic functional unit. Separated from each other by dark bands called Z lines. Calcium and ATP molecule required to contract

Question 11

Movement: prime mover

Answer 11

Muscle whose contraction is mainly responsible for producing movement

Question 12

Movement: synergist

Answer 12

Muscle whose contractions help prime mover produce movement

Question 13

Movement: antagonist

Answer 13

Muscle whose actions oppose the action of a prime mover

Question 14

Posture

Answer 14

Tonic contraction allow us to maintain posture. No movement of body parts

Question 15

Motor unit: motor neuron

Answer 15

Nerve cell that transmits impulse to a muscle causing contraction

Question 16

Motor unit: neuromuscular junction

Answer 16

Point of contact between nerve ending and muscle fiber it innervates

Question 17

Threshold stimulus

Answer 17

Muscle will contract only if an applied stimulus reaches certain min level of intensity

Question 18

4 types of Muscle contractions

Answer 18

Twitch: quick responses to stimulus
Tetanic: sustained and steady muscular contractions caused by series of stimuli bombarding a muscle in rapid succession
Isotonic
Isometric

Question 19

Isotonic contractions

Answer 19

Produces movement at a joint. Muscle changes length
Concentric contractions shorten muscle
Eccentric contractions increase muscle length

Question 20

Isometric contractions

Answer 20

Muscle contractions that do not produce movement or Changes length of muscle.
Tension in muscle increases

Question 21

Muscles of mastication

Answer 21

Masseter: closes jaw

Temporal

Question 22

Sternocleidomastoid

Answer 22

Flexes head