Muscular System

Question 1

What must be present in order for a muscle cell to contract?

Answer 1

Calcium and ATP

Question 2

Synergists:

Answer 2

Work in cooperation with the prime mover

Question 3

Flexors:

Answer 3

Reduce the angle at the joint

Question 4

Extensors:

Answer 4

Increase the angle at the joint

Question 5

Abductors:

Answer 5

Draw a limb away from the midline

Question 6

Adductors:

Answer 6

Return the limb back toward the body

Question 7

How do muscle cells contract?

Answer 7

1. Nervous stimulation from motor neurons causes release of calcium ions from the sarcoplasmic reticulum
2. Calcium ions attach to inhibitory proteins on actin filaments, moving them aside so cross-bridges can form between actin and myosin filaments
3. Using energy supplied by ATP, the filaments slide together to produce contraction

Question 8

Sarcomere:

Answer 8

Smaller subunits of myofibrils, contractile

Question 9

Skeletal muscles (which make up the muscular system) must work in pairs:

Answer 9

The muscle that executes movement is the prime mover.

The muscle that produces the opposite movement is the antagonist.

Question 10

Myofibril:

Answer 10

Tightly packed filament bundles found within skeletal muscle fibers

Question 11

Dorsiflexion:

Answer 11

Ankle flexion (moving the toes toward the shin)

Question 12

Plantar flexion:

Answer 12

Ankle extension (moving toes toward the ground/pointing the toes)

Question 13

Myosin:

Answer 13

Thick filaments

Question 14

Actin:

Answer 14

Thin filaments

Question 15

Insertion:

Answer 15

Attachment to movable bone

Question 16

Origin:

Answer 16

Attachment of the muscle to the bone that remains stationary

Question 17

Motor neurons of the ANS consist of 2 neurons:

Answer 17

Preganglionic and postganglionic

Question 18

Smooth (visceral) Muscle:

Answer 18

• Nonstriated
• Involuntary
• Found inside: organs, blood vessel, and airway walls

Question 19

Cardiac Muscle:

Answer 19

• Striated
• Involuntary
• Arrhythmic
• Interconnected

Question 20

Skeletal muscle is:

Answer 20

Striated and voluntary

Question 21

Quadricep muscles:

Answer 21

Vastus lateralis (lateral)
Vastus intermedius (intermediate)
Vastus medialus (medial)