Unit 8: Muscular

Question 1

What are the four main functions of the muscular system?

Answer 1

Movement, Posture, Stabliize Joints, and Generate heat.

Question 2

How does the muscular system generate heat?

Answer 2

It is generated through muscle contractions and is how the majority of the body’s temperature is maintained.

Question 3

What is the endomysium?

Answer 3

It is the connective sheath covering muscle fiber.

Question 4

What is the perimysium

Answer 4

It covers a group of muscle fibers.

Question 5

What is a tendon?

Answer 5

It attaches muscle to bone

Question 6

What is the epimysium?

Answer 6

It covers a group
of fascicles which to the entire muscle

Question 7

What is a motor unit?

Answer 7

It is one neuron and all the muscle fibers it stimulates

Question 8

How does the sarcoplasmic reticulum affect muscle contractions?

Answer 8

It stores the calcium that is required for muscle contractions. In a relaxed muscle there is lots of calcium stored in the SR and the gates are closed.

Question 9

How do the transverse tubules affect muscle contractions?

Answer 9

The transverse tubules or t-tubes deivers the actions potential to the muscle cell. It communicated with the sarcoplasmic reticulum.

Question 10

What are the effects of aerobic or endurance exercises?

Answer 10

They create stronger and more flexible muscles that have a greater resistance to fatigue. There are increased mitochondria, blood suppy, metabolism, and better meuromusclar coordiantion. It created a stronger skeleton, and increased heart size. It helps remove artherosclerosis and created more efficient lungs.

Question 11

How does calcium intitiate a muscle contraction?

Answer 11

When the SR releases calcium it binds to troponin. This complex moves the tropomysoin to reaveal the actin binding site so the myosin head can attach.

Question 12

What is the effect of resistance/isometric exercises?

Answer 12

It causes an increase in muscle size due to an increased number of myofilaments. There is also increased connective tissue to reinforce muscles.

Question 13

What is the cause of rigor mortis?

Answer 13

Rigor mortis is caused by a lack of ATP, so it in a continual contraction.

Question 14

What causes an increase in muscle size?

Answer 14

As you work out you cause tiny tears in the microfilaments, which then are repaired, but new microfilaments are added which causes the muscle to increase in size.

Question 15

What is the function of ATP during muscle contraction?

Answer 15

It releases the myosin head from teh actin binding site, provides energy to spring-load the myosin head, and provides energy to put the calcium back into the SR.

Question 16

What factor is the most responsible for the muscle soreness felt 2-3 days after a high intensity workout?

Answer 16

The buildup of lactic acid is the most responsible and inflammed muscles and repair.

Question 17

What is a sarcomere?

Answer 17

It is the functional unit of myofibril

Question 18

What is the “all-or-none” response in a muscle cell?

Answer 18

It applies to the individual muscle cells, an indivdual muscle cell will contract to its fulest when stimulated

Question 18

What is a graded response?

Answer 18

Different degrees of shortening based on stimuli

Question 19

What is the sliding filament theory of muscle contraction?

Answer 19

It is the idea that when a muscle contracts the thin and thick filaments will begin to slide across each other and overlap to perform a contraction.

Question 20

What is a twitch?

Answer 20

When one muscle fiber contracts in response to a command (stimulus) by the nervous system

Question 20

What is isometric contraction?

Answer 20

A pull agaisnt an immovable object - a plank

Question 20

What is tetanus?

Answer 20

A smooth muscle contraction aused by fused tetanus

Question 21

What is istonic contraction?

Answer 21

It is a contraction with a change in myofilament length - like walking and running - a pushup

Question 22

What are three ways to get energy for muscle contractions?

Answer 22

Creatine Phosphate, Glycolysis, and oxidative phosphorylation

Question 22

What is the process of creatine phosphate?

Answer 22

Creatine Phospahte stores ATP energy during rest, it is 4-6x more abundant than ATP and it is only found in muscle cells. It is depleted in about 20 seconds.

Question 23

What is aerobic respiration?

Answer 23

Also known as oxidative phosphorylation, it is the slowest and most effient method. It uses oxygen and it used at rest with light or endurance exercise. I gluceose creates 36 ATP. It uses fat, glucose, and protein.

Question 25

What is anaerobic respiration?

Answer 25

It is when glycogen is boken down to glucose and is then used to make ATP. THi causes lactic acid to be produce. It is 2.5 times faster than aerobic respiration.