The Nervous System
What is the threshold for an action potential?
-55mV
The globular heads on myosin have binding sites for _____ and ______.
Actin and ATP
This level is responsible for generating intention.
Highest Level
What is the difference between an endocrine and an exocrine gland?
An endocrine gland secretes hormones into the interstitial fluid, which then diffuse into the blood
An exocrine gland secretes a product via a duct (mammary gland, sweat gland)
This type of leukocyte plays a role in protecting the body against parasites.
Eosinophils
What brings the cell back to the resting membrane potential after hyperpolarization
Na+/K+ ATPase Pump. It Pumps out 3 Na+ and Brings in 2K+
List the levels of skeletal muscle structure from largest to smallest.
Muscle, Fascicle (bundle of muscle fibers), muscle fibers (muscle cells), myofibrils, sarcomeres, thick and thin protein filaments.
What is gray matter, white matter, and nuclei?
Gray matter: composed of neuron cell bodies
White Matter: composed of myelinated axons
Nuclei: pockets of gray matter
This class of hormone is derived from the amino acid tyrosine, is water soluble, and an example of one hormone is epinephrine.
Amine
This valve prevents blood from moving back into the right atrium after it has moved into the right ventricle.
Tricuspid valve
An Influx of _____ causes neurotransmitter________ to be released into the synaptic cleft.
Influx of Ca2+. Neurotransmitter Acetylcholine
Which organelle is responsible for releasing Ca 2+ during a skeletal muscle contraction?
Sarcoplasmic Reticulum
This type of reflex happens when you tap on the patellar tendon. Is it monosynaptic or polysynaptic?
Knee jerk reflex. Monosynaptic
This is a larger protein/peptide that eventually gets cut into a peptide or protein hormone.
Prohormone
This carries deoxygenated blood to the lungs where the blood becomes oxygenated.
Pulmonary arteries
What are the steps of neurotransmitter release?
1. The impulse reaches the axon ending of the presynaptic membrane
2. Synaptic vesicles release neurotransmitter into the synaptic cleft
3. Neurotransmitter diffuses across the synaptic cleft
4. Neurotransmitter molecules bind to receptors on the postsynaptic neuron
5. Sodium ion channel opens
6. Sodium ions enter the postsynaptic neuron, causing depolarization and
What is the thick filament made out of? What is the thin filament made out of, including the two regulatory proteins)?
Thick filaments- Myosin
Thin filaments- Actin. Regulatory proteins of thin filaments: troponin and tropomyosin
All of the information going up to the cortex passes through….
Thalamus
Name the hormones secreted by the anterior pituitary gland
FSH, LH, ACTH, TSH, Prolactin, Growth Hormone (A mnemonic to remember them is “FLAT PiG”
The QRS wave seen in an electrocardiogram represents what?
Depolarization of the ventricles
Describe the steps of an action potential (resting potential, depolarization, repolarization, hyperpolarization, Na+/K+ ATPase Pump).
Resting potential- -70mV, more (-) inside, more Na+ outside
Depolarization- AP begins once -55mV (threshold) is reached, Large influx of Na+, neuron is becoming more positive than at rest
Repolarization- Large efflux of K+, neuron becoming more negative again
Hyperpolarization- even more (-) than at rest,
Na+/K+ ATPase pump establishes resting potential by pumping out 3Na+ and pumping in 2K+
Describe muscle contraction steps beginning with “Neurotransmitter acetylcholine binds to muscle fibers….”
Neurotransmitter acetylcholine binds to muscle fibers.
This sends an action potential down the t-tubules
That AP triggers sarcoplasmic reticulum to release Ca2+
Ca2+ binds to troponin
This causes a conformational change and pulls tropomyosin away from binding site
Binding site on actin is now exposed =cross bridge cycle starts
Myosin head will bind to binding site on actin with the help of hydrolysis of ATP---> ADP + P
Power stroke occurs(actin to m-line)-sliding filament mechanism
Describe the muscle spindle fibers and the motor neurons that innervate them.
Extrafusal Muscle Fibers provide force and movement. Innervated by alpha motor neurons.
Intrafusal Muscle Fibers provide sensory input. Innervated by Gamma motor neurons.
Note, alpha-gamma coactivation insures info about muscle length is continuously available
Where on the target cell are receptors for peptide and amine hormones?
Where on the target cell are receptors for steroid hormones?
receptors for peptide and amine hormones? A: Cell surface
receptors for steroid hormones? A: intracellular
Summarize the blood flow through the heart.
Vena Cava, Right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary artery, lungs, back through the pulmonary vein, left atrium, mitral valve (bicuspid valve), left ventricle, aortic valve, aorta…takes it to the body and then it will eventually return through the vena cava back to the right atrium again.