Chapter 1: Structure and Functions of the Body

Question 1

Describe the Macrostructure of Muscles

Answer 1

Large, Visiablestructures

Organs

Skeletal Muscles that contain muscle tissue, connective tissue, nerves, and blood vessels.

Question 2

Describe Microstructures of Muscles

Answer 2

Connective Muscle Layers:
AKA Schematic of a muscle:

Epimysium ——(the outer layer)

Perimysium ——(surrounding each fasciculus/group of
fibers)

Endomysium—— (surrounding individual fibers)

Question 3

Where does muscle growth occur on a cellular level?

Answer 3

Adds to Actin and Myosin

Question 4

What is a sarcomere?

Answer 4

Functional contractile unit of muscle
Primarily made of Actin and myosin
Measured from z line to z line

Question 5

What are Myofilaments?

Answer 5

Actin & Myosin

Question 6

Actin

Answer 6

Thin filament
Molecules arranged in double helices
(like DNA)

Question 7

Myosin

Answer 7

Thick Filament with the cross-bridge heads

pulls z-line toward center of sarcomere and shortening the muscle fiber

Question 8

What are the 5 phases of the sliding filament theory?

Answer 8

1. Resting phase
   —Little Ca in Sarcoplasm
   — Myosin heads detached
   —Tripomyosin covers binding sites on actin
2. Excitation-Contraction coupling phase
   —Ca released from action potential
   — Ca binds to Troponin = conformational shift
   — Troponin pulls tropomyosin away
   — Myosin headds bind to actin
3. Contraction Phase
   —Cocked heads
   — Power storke (myosin fires and attches)
   —ATP binds to myosin, making to release
   — ATP hydrolyzed by ATPase and releases energy
   — Back in the cocked position
4. Recharge Phase
   —continues as long as there is Ca, ATP and ATPase
5. Relaxation phase
   — Ca os sequestered, preventing heads from contracting
   — CA is pumped (takes energy) back into SR

Question 9

Motor end plate

Answer 9

The muscle fiber area is innervated by a motor neuron (axonal terminal)

—Muscle site of axonal terminal—

Question 10

Acetylcholine

Answer 10

Neurotransmitters released by motor neuron NMJ

Question 11

Action potential

Question 12

All-or-None principle

Question 13

Twitch

Question 14

Summation

Question 15

Motor Unit

Question 16

Tetanus

Question 17

…..

Question 18

Proprioception

Answer 18

Kinesthetic sense
(aware of where the body is)

Question 19

Proprioceptors

Answer 19

Specialized sensory receptors that give you the kinesthetic sense

Roles:
——Facilitate activation of muscle contraction

––in between the fibers (parallel)

Question 20

Golgi Tendon Organs

Answer 20

In series with extrafusal fibers
where the tendon and muscle meet (at the myotendinous junction)

Roles:
Inhibits muscle activation when too heavy
——inhibits motor neurons if force is excessive
–– occurs with resistance training

Question 21

Muscle Spindle

Answer 21

Stretch Reflex (stretch-shortening cycle, squat before jump)
An important part of an SSC

They tell when a muscle is stretched, deformed muscle, neuron causing the muscle to contract)

Question 22

What are the primary functions of Cardiovascular functions?

Answer 22

1. Transport nutrients
2. Removes waste products
3. Aids in regulation of:
   —Acid Balance
   —Fluid Compartments (sweating)
   —Temperature

Question 23

Types of Blood vessels …..

Question 24

What are the two major functions of the blood?

Answer 24

Transpots O2 form lungs to tissues
Transports CO2 from tissues to lungs

Can regulate acid-bases

Question 25

Neuromuscular activity is supported through continuous delivery of O2 (and energy yielding nutrients; e.g., glucose) to and removal of CO2 (and other waste products; e.g., H+) from working tissues via_____ and ____ systems

Answer 25

Respiratory and Cardiovascular

Question 26

What is the purpose of a Sarcoplasmic reticulum and T-Tublules

Answer 26

SR
—Network of tublules
—Calcium

T-Tubules
—AP Propagation