Flashcards in Chapter 2 - Basic Exercise Science Deck (120)
Explain the process of neurotransmitters and what the specific neurotransmitter used by the neuromuscular system is called.
1. Once released, they link with receptor sites on the muscle fiber specifically designed for their attachment.
2. Once attached, ACh (acetylcholine -neurotransmitter used by neuromuscular system) stimulates the muscle fibers to go through a series of steps that initiates muscle contractions.
What are Neurotransmitters?
- Chemical messengers that cross the neuromuscular joint junction (synapse) to transmit electrical impulses from the nerve to the muscle.
What is the Sliding Filament Theory? List/describe the steps.
-The proposed process by which the contraction of the filaments within the sarcomere take place.
-Describes how thick and thin filaments within the Sacromere slide past one another, shortening the entire length of the Sacromere and thus shortening the muscle and producing force.
1. A sarcomere shortens as a result of the Z lines moving closer together.
2. The Z lines converge as a result of myosin heads attaching to the actin filament and asynchronously pulling (power strokes) the actin filament across the myosin, resulting in shortening of the muscle fiber.
What are "Z" lines?
I don't know!!!
Describe Excitation-Contraction Coupling
- The process of neural stimulation creating a muscle contraction.
- It involves a series of steps that start with the initiation of a neural message (neural activation) and end up with a muscle contraction (sliding filament theory).
Explain the "All or Nothing" law of Motor Units.
-Bottom Line: Motor units cannot vary the amount of force they generate; they either contract maximally or not at all.
1. If the stimulus is strong enough to trigger an action potential, then it will spread through the whole length of the muscle fiber. It will spread through all muscle fibers supplied by a single nerve.
2. If the stimulus is not strong enough, then there will be no action potential and no muscle contraction.
Describe Type I Muscle Fibers
- Slow twitch
- Large number of capillaries, mitochondria (which transforms energy from food into ATP, or cellular energy), and myoglobin, which allows for improved delivery of oxygen.
- Smaller in size
- Slow to fatigue
- Long-term contractions (stabilization)
- Sitting upright while maintaining ideal posture against gravity, for an extended period of time.
-Referred to as "Red Fibers" as it is similar to hemoglobin (red pigment found in red blood cells)
Describe Type II Muscle Fibers
- Separated into 2 subdivisions based off vehemently and mechanical properties (Type IIa and Type IIx)
- Fewer capillaries, mitochondria, and myoglobin
- Known as "white fibers"
1. Type IIa - higher oxidative capacity and fatigued more slowly than Type IIx - known as intermediate fast-twitch fibers because can use both aerobic and anaerobic metabolism almost equally to create energy making them a combo of Type I and Type II.
2. Type IIx- low oxidative capacity (ability to use oxygen) and fatigue quickly.
-example: movements requiring force and power like a sprint.
Describe the 4 types of muscle functions and give an example.
1. Agonist: Prime Mover - muscles most responsible for a particular movement. Ex. gluteus maximus is an agonist for hip extension.
2. Synergist: Assist Prime Mover - Ex. the hamstring complex and the erector spinae are synergist with the gluteus maximus during hip extension.
3. Stabilizer: Stabilize Body While Prime Mover and Synergist Work - Ex. tansversus abdominis, internal oblique, and multifidus (deep muscles in lower back) stabilize low back, pelvis, and hips (lumbo-pelvic-hip complex) during hip extension.
4. Antagonist: Oppose Prime Mover - Ex. the psoas (a deep hip flexor) is antagonistic to the gluteus maximus during hip extension.
Describe the Endocrine System and what it consists of.
- literal meaning: "Hormone Secreting"
- The system of glands that secrete hormones into the bloodstream to regulate the control of mood, growth and development, tissue function, and metabolism.
- Host organs (glands)
- Chemical messengers (hormones)
- Target (receptor) cells.
Special proteins will bind to some hormones, acting as carries that control the amount of hormone that is available to interact with and affect the target cells.
Decribe types of human function that the endocrine system's hormones affect.
- Triggering muscle contraction
- Stimulating protein and fat synthesis
- Activating enzyme systems
- Regulating growth and metabolism
- Determine how the body will physically and emotionally respond to stress.
Describe the hormones secreted from the anterior lobe of the pituitary gland.
1. growth hormone, prolactin to stimulate milk production after giving birth
2. adrenocorticorophic hormone (ACTH) to stimulate adrenal glands
3. thyroid-stimulating hormone (TSH) to stimulate thyroid gland
4. follicle-stimulating hormone (FSH) to stimulate ovaries and testes
5. luteinizing hormone (LH) to stimulate the ovaries or testes.
What are the 4 Primary endocrine glands?
2. Pituitary ("master" gland because is controls the functions of the other endrocirine glands)
4. Adrenal glands.
Describe the hormone secreted from the intermediate lobe of the pituitary gland.
secretes melanocyte-stimulating hormone to control skin pigmentation
Describe the hormone secreted from the posterior lobe of the pituitary gland.
1. antidiuretic hormone (ADH) to increase absorption of water into the blood by the kidneys
2. oxytocin to contract the uterus during childbirth and stimulate milk production
What hormones does the thyroid gland affect and regulate.
produces hormones that regulate the rate of metabolism and affect the growth and rate of function of many other systems in the body.
What hormones do the adrenal glands secrete and in response to what?
secrete hormones such as corticosteroids and catecholamines, including cortisol and adrenaline (epinephrine) in response to stress.
What is the primary energy source used during vigorous exercise? What is it regulated by?
Carbohydrate, specifically glucose (also principal fuel for the brain) regulated by the pancreas which produces two specific hormones: insulin and glucagon.
What is Insulin?
A protein hormone released by the pancreas that helps glucose move out of the blood and into the cells in the body, where the glucose can be used as energy and nourishment.
What are the two catecholamines (hormones produced in the adrenal glands) used during "fight or flight" response (aka. stress)?
What are the physiological effects that occur during this response that help sustain exercise activitiy?
1. Epinephrine (adrenaline)
-increases heart rate and stroke volume
-elevates blood glucose levels
-redistributes blood to working tissues
-opens up the airways
What is Glucagon?
The complex carbohydrate molecule used to store carbohydrates in the liver and muscle cells. When carbohydrate energy is needed, glycogen is converted into glucose for use by the muscle cells.
What is the primary use of testosterone in both men and women in regards to exercise.
-Fundamental role in growth and tissue repair.
-Raised levels of testosterone are indicative of an anabolic (tissue building) training status.
What is the purpose of Cortisol?
Under times of stress, such as exercise, cortisol is secreted by the adrenal glands and serves to maintain energy supply through the breakdown of carbohydrates, fats, and proteins.
What is Growth Hormone/What it is responsible for? What type of hormone is it primarily? What can it be stimulated by?
- Responsible for most of the growth and development during childhood up to puberty, when primary sex hormones take over that control.
-Increase development of bone, muscle tissue, and protein synthesis; increases fat burning; and strengthens the immune system.
- Primarily an anabolic hormone
- Stimulate by several factors (estrogen, testosterone, deep sleep, and vigorous exercise).
Where is the Trochanter process located? The greater trochanter is commonly called _______.
- Located at the top of the femur and are the attachment sites for the hip musculature.
- The greater trochanter is commonly called the hipbone.
Describe Thyroid gland's primary role and what it is regulated by.
- Responsible for human metabolism (carbohydrate, protein and fat metabolism), basal metabolic rate, protein sythesis, sensitivity to epiniephrine, heart rate, breathing rate, and body temperature.
- Regulated by pituitary gland
- **low thyroid: low metabolism, fatigue, depression, sensitivity to cold, an weight gain.
Where is the Tubercle process located? There are greater and lesser tubercles, which are attachment sites for ______ musculature.
- Located at the top of the humerus at the glenohumeral (shoulder) joint.
- Shoulder Musculature.
Where is the Epicondyle process located?
- Located on the inner and outer portions of the humerus to help form the elbow joint.
Where is the Condyle process located?
- Located on the inner and out portions at the bottom of the femur (thigh bone) and top of the tibia (shin bone) to form the knee joint.