Ch 2: Fundamental Human Movement Science - Muscles and Endocrine System

Question 1

What are the three muscle types?

Answer 1

Skeletal muscle
Cardiac muscle
Smooth muscle

Question 2

Tendon

Answer 2

Connective tissues that attach muscle to Bone and provide an anchor for muscles to produce Force

Question 3

Neural activation

Answer 3

The contraction of a muscle generated by neural stimulation

Question 4

Motor unit

Answer 4

A motor neuron and all of the muscle fibers it innervates or activates

Question 5

Neurotransmitters

Answer 5

Chemical Messengers that cross the neuromuscular junction (synapse) to transmit electrical impulses from the nerve to the muscle

Question 6

What is the neurotransmitter used by the muscular system?

Answer 6

ACh

Question 7

What is the neurotransmitter used by the muscular system?

Answer 7

ACh (acetylcholine)

Question 8

The All or nothing law

Answer 8

Motor units cannot vary the amount of force they generate they either contract maximally or not at all. A motor unit must innervate all of the muscle fibers joined to it.

Question 9

Type 1 muscle fibers

Answer 9

Slow twitch or red fibers contain a large number of capillaries mitochondria and myoglobin they are slow to contract and slow to fatigue.

Question 10

Type IIx muscle fibers

Answer 10

Type 2 fibers or fast twitch or white muscle fibers have lower oxidative capacity, fatigue quickly, and typically contain fewer capillaries mitochondria and myoglobin

Question 11

Type IIa muscle fibers

Answer 11

Type IIa muscle fibers are also known as intermediate fast which fibers they can use both aerobic and anaerobic metabolism almost equally to create energy in this way they are a combination of type 1 and type 2 muscle fibers

Question 12

Endocrine System

Answer 12

The endocrine system is a system of glands that secrete hormones into the bloodstream to regulate a variety of bodily functions including the control of mood, growth and development, tissue function, and metabolism. The endocrine system consists of host organs (known as glands) chemical Messengers (hormones) and Target (receptor) cells.

Question 13

Primary endocrine glands

Answer 13

Pituitary gland, hypothalamus, thyroid, and adrenal glands.

Question 14

Function of the pancreas

Answer 14

Control of blood glucose is regulated by the pancreas which produces two specific hormones insulin and glucagon.

Question 15

Insulin function

Answer 15

As blood is circulated through the pancreas elevated levels of glucose trigger the release of insulin circulating insulin binds with the receptors of its target cells and skeletal muscle or liver cells the cell membrane becomes more permeable the glucose. Glucose then diffuses out of the bloodstream and into the cell the net result is a drop in blood glucose levels thus insulin causes cells in the liver muscle and fat tissue to take up glucose from the blood storing it as glycogen in the liver and muscle.

Question 16

Function of glucagon

Answer 16

Glucagon functions to raise blood glucose levels by triggering the release of glycogen stores from the liver.

Question 17

Catecholamines

Answer 17

Epinephrine and nor epinephrine are hormones produced by the adrenal glands which are situated on top of each kidney they are responsible for the fight or flight response.

Question 18

Effects of catecholamines

Answer 18

Increased heart rate and stroke volume
Elevated blood glucose levels
Redistributes blood to working tissues
Opens up the airways.

Question 19

Cortisol

Answer 19

Typically referred to as a catabolic hormone. Under times of stress such as exercise cortisol is secreted by the adrenal gland and serves to maintain energy supply through the breakdown of carbohydrates fats and protein. High levels of cortisol brought about through overtraining excessive stress poor sleep and inadequate nutrition can lead to significant breakdown of muscle tissue along with other potentially harmful side effects.

Question 20

Growth Hormone

Answer 20

Growth hormone is primarily an anabolic hormone that is responsible for most of the growth and development during childhood up until puberty. Growth hormone also increases the development of bone, muscle tissue, and protein synthesis; increases fat burning semicolon and strengthens the immune system.

Question 21

Thyroid Hormones

Answer 21

Primarily responsible for human metabolism. Thyroid hormones have been shown to be responsible for carbohydrate, protein, and fat metabolism, basil metabolic rate, protein synthesis, sensitivity to epinephrine, heart rate, breathing rate, and body temperature. Low thyroid function has become a well recognized sorter leading to low metabolism, fatigue, depression, sensitivity to cold, and weight gain.

Question 22

Effects of exercise

Answer 22

Research has indicated that to test testosterone and growth hormone levels increase after strength training and moderate to vigorous aerobic exercise a similar pattern also seems to emerge for cortisol