Musculoskeletal system

Question 1

Skeletal muscle

Answer 1

Responsible for voluntary movement and is innervated by somatic nervous system

Question 2

Smooth muscle

Answer 2

Involuntary. Controlled by autonomic nervous system. Capable of more sustained contractions. Exhibits myogenic activity

Question 3

Cardiac muscle

Answer 3

Contraction is involuntary and is innervated by ANS. Connected by intercalated discs which contain GAP junctions. Exhibit myogenic activity.

Question 4

Myogenic activity

Answer 4

Contraction without nervous system input

Question 5

Sliding Filament Model

Answer 5

1. Resting Stage; ATP is hydrolyzed
2. Ca²⁺ binds to troponin; myosin binds to actin
3. Powerstroke occurs; ADP and P_i dissociate from myosin
4. New ATP binds to myosin, causing detachment from actin; ATP hydrolysis causes recocking

Question 6

Simple twitch vs. Tetanus

Answer 6

Question 7

Long bone anatomy

Answer 7

Question 8

Compact bone

Answer 8

Dense and strong; used for protect and support

Question 9

Spongy bone

Answer 9

Used to support; made of trabeculae which can be remodeled in response to external forces

Question 10

Bone marrow

Answer 10

Lies within trabeculae and marrow cavities

Red: active, hematopoetic stem cells

Yellow: inactive, composed of fat

Question 11

Periosteum

Answer 11

Surrounds the bone; has osteogenic properties and is a site for muscle attachment

Question 12

Osteoblasts vs. Osteoclasts

Answer 12

Osteoblasts build bone

Osteoclasts chew bone

Question 13

Parathyroid hormone

Answer 13

Released by parathyroid glands in response to low blood Ca²⁺

Question 14

Calcitonin

Answer 14

Released by parafollicular cells of the thyroid in response to high blood Ca²⁺