Exam Two Flashcards
List the primary branches of the Peripheral Nervous System
- Somatic
- Autonomic (Sympathetic and Parasympathetic)
What does each branch of the peripheral nervous system do? (6)
Sensory Nerves: tells the CNS whats going on
Effector Nerves: sends information from the CNS to the tissues/organs
Somatic: voluntary movement
Autonomic: involuntary
-Sympathetic: fight or flight
-Parasympathetic: rest and digest
What are the nerves that send signals to and from the periphery?
Neurons
Nerves: bundles of neurons along with CT
Identify the primary components of a Neuron
How do neurons communicate?
Via electrical impulses
What is an action potential?
Rapid depolarization passed down a neuron
What is the neuron’s resting membrane potential
Negative electrical potential of -70mV
Polarization: difference in charge between the outside and inside of a cell due to concentration of Ions
What are the sodium-potassium pumps? What do they do when activated?
Changes the concentration of Na and K in the cell membrane by pumping them in and out of the cell
Define depolarization, hyper-polarization, and repolarization
Depolarization: Negative to positive
Hyper-polarization: makes the cell even more negative
Repolarization: Positive to negative
What factors affect the speed of an action potential?
- Myelination of Axon: fatty myelin sheaths that insulate the cell membrane
- Diameter of the Axon: larger neurons conduct faster
Describe the differences between a synapse and neuromuscular junction
Synapse: junction between a neuron and a cell
Neuromuscular Junction: site where alpha-motor neuron communicates with a muscle fiber
How does exercise affect the neuromuscular junction?
Increased release of acetylcholine, sensitivity of the muscle to acetylcholine
Define neural fatigue
Acute exercise can decrease motor nerve outflow and transmission rates
Define the different regions of the brain and how each may be involved in exercise. (5)
Primary Motor Cortex: site of conscious movement
Basal Ganglia: site of repetitive, unconscious movement
Diencephalon: Thalamus (sense are processed and relayed to appropriate cortex) Hypothalamus (maintains homeostasis)
Cerebellum: coordinates changes in the body with activity
Brain Stem: autonomic center for respiration and cardiovascular system
Define neuroplasticity
Ability of the brain to change, adapt and develop new pathways
List the types of receptors located around the body and their primary functions (5)
Mechanoreceptors- pressure, touch, vibration, or stretch
Thermoreceptors- temp
Nociceptors- pain
Photoreceptors- light
Chemoreceptors- changes in O2 and CO2, glucose, smell, etc.
List the effects that sympathetic nervous stimulation has on the body
- Fight or flight
- Prolong stress
Define how the muscle spindle and Golgi tendon organ work
Muscle Spindle: sends info to the CNS about muscle length or degree of stretch
Golgi Tendon: strain-gauge in the muscle tendon complex, inhibits the active muscle
How do steroid and non-steroid hormones work?
Steroid Hormones: derived from cholesterol, passes through cell membrane
Non-steroid Hormones: not fat-soluble, can not pass through cell membrane and acts on the receptors on the cell membrane
What are prostaglandins?
May be classified as hormones Derived from the fatty acid arachidonic acid Autocrine: locally acting hormones Promotes inflammation Produced by COX enzymes
What do Downregulation/Desensitization and Upregulation mean (regarding hormone actions)?
Down-regulation: number of hormone receptors on a cell can decrease
Up-regulation: increase number receptor on a cell can decrease
Hormones of the Pituitary Gland (6)
- Growth hormones: cell growth
- TSH: controls release of thyroid hormones
- ACTH: controls hormones of the adrenal cortex
- Prolactin: stimulates milk production
- FSH: stimulates estrogen secretion from ovaries or sperm production in testes
- LH: stimulates estrogen and progesterone secretion, or testes to secrete testosterone
Hormones of the Thyroid Gland
- T3 and T4: increases metabolic rate, increase protein synthesis, size of mitochondria, glucose uptake
- Calcitonin: controls calcium concentration in blood
Hormones of the Adrenal Gland (5)
Catecholamines (epinephrine and Norepinephrine):
-increase HR, metabolic rate, blood to muscles, respiration, BP
-stimulates release of glucose and fatty acid into the blood
Corticosteroids:
-Mineralocortiods: aldosterone (increases sodium retention
-Gonadocorticoids: androgens and estrogen
-glucocorticoids: cortisol (primary glucorticoid)
Cortisol
- stimulates release of glucose and fatty acid
- spare use of glucose for the brain
- breaks down protein for fuel
- anti-inflammatory
- depress immune reaction
Hormones of the Pancreas
- insulin: cells to take un glucose and amino acids
- glucagon: signals liver to release glucose into the blood
Briefly define osmotic pressure and how solvents/solutes control fluid balance.
pressure required to stop water from diffusing through a semi-permeable membrane
List the steps of the Renin-Angiotensin-Aldosterone System.
- Renin is released
- Angiotensin is converted to angiotensin 1
- angiotensin converting enzyme in the lung
- Angiotensin 2 to adrenal cortex
- Adrenal cortex release aldosterone and vasoconstriction
How are Growth Hormone and Cortisol affected by Circadian Rhythm?
stimulated by intense exercise but increases almost only during sleep
What is a Calorie/kilocalorie?
amount of heat required to raise 1kg of water to 1C
Define direct and indirect calorimetry.
Direct: directly measuring heat production in an enclosed chamber
Indirect: estimating energy expenditure by the respiratory exchange of O2 and CO2
What are the limitation of direct and indirect calorimetry
Direct: is very expensive, equipment can give of heat, the body stores heat that can not be detected
Indirect: not as accurate
Define the standardization of gas between different environments.
Expired air is at body temp, atmospheric pressure, and saturated with water vapor
BTPS
BTPS: Body Temperature Pressure Saturated.
volume of gas is dependent upon the body temperature at a barometric pressure that is saturated with water vapor.
temperature of the body is 37 ºC
the amount of saturated water vapor pressure associated with 37 ºC is 47 mm Hg
How do you calculate RER
RER= VCO2/VO2
What RER values are associated with oxidation of carbohydrates or fats?
O.7-1.0
Briefly describe the Doubly Labeled Water technique (don’t go into details).
Person consumes water with know quantity of Hydrogen and Oxygen. Measures the difference between hydrogen and oxygen isotopes leaving the body
What factors determine an individual’s daily energy expenditure?
have to have:
- 30 mins of doing nothing
- dimly lit, thermoneutral room
- 12-hour fast
- no intense exercise for 12 hours
ATPS
Ambient Temperature Pressure Saturated.
volume of gas is dependent upon the ambient temperature at a barometric pressure (Pb) that is saturated with water vapor.
For our purpose, the barometric pressure will be 760 mm Hg (sea level).
STPD
(0°C or 273 K) and pressure (760 mm Hg) and dry (no water vapor).
