BIOL 235 MIDTERM 2A EXAM QUESTIONS AND ANSWERS 100% PASS

BIOL 235 MIDTERM 2A EXAM QUESTIONS AND ANSWERS 100% PASS sympathetic stimulation - The process that results in preparing the body for exercise; "fight or flight" mechanism; - increased heart rate - dilated pupils constriction of kidneys and digestive tract alpha receptors - adrenergic receptors that are found in smooth muscles and constrict arteries when stimulated by norepinephrine and epinephrine; increases bp and blood flow to heart A1 receptors - involved in smooth muscle contraction; - contraction of bronchioles, blood vessels, internal urethral sphincter, and muscular wall 2 100% Pass Guarantee Katelyn Whitman, All Rights A2 receptors - -Located on presynaptic axons -When stimulated, result in inhibition of norepinephrine release in the synapse; this may be a negative-feedback system Beta receptors - adrenergic receptors that are found in the heart, lungs, and vascular smooth muscle; involved in the relaxation of cells and dilation of blood vessels and found on tissues throughout the body B1 receptors - increase cardiac output by increasing heart rate, stroke volume, and rate of relaxation through dilation B2 receptors - smooth muscle relaxation throughout the body; ex) relaxation of muscular war and relaxation of internal urethral sphincter muscarinic ACH receptors - Can be stimulated by muscarine (from poisonous mushrooms) Found in CNS and plasma membrane of smooth and cardiac muscles and glands innervated by autonomic motor neurons; triggers parasympathetic stimulation 3 100% Pass Guarantee Katelyn Whitman, All Rights parasympathetic stimulation - 'rest and digest'; lowers ventilation rate, release blood flow to gut and other organs, decrease heart rate and bp water soluble hormone - a lipophobic hormone that binds to a receptor on or within the plasma membrane to initiate an intracellular signalling cascade ex) glucagon, insulin, ADH, oxytocin water soluble hormone steps - 1. bind to receptors on the surface of the cell which are coupled to internally anchored G proteins 2. signal transduction: the receptor complex activates second messenged (cAMP, Ca2+) which initiate cell activity 3. use of second messengers enables the amplification of the initial signal as more molecules are activated (enzyme cascade) 4. enzyme 3 stimulates the breakdown of glycogen into glucose lipid soluble hormone - liphophilic hormone that can move freely into membrane and into cell ex) progesterone, estrogen, testosterone lipid soluble hormone steps - 1. hormone diffuses through the plasma membrane of the target cell 4 100% Pass Guarantee Katelyn Whitman, All Rights 2. the hormone binds to a receptor in cytoplasm 3. the hormone receptor complex enters the nucleus 4. the hormone receptor complex binds to DNA 5. genes are then transcribed and made proteins are synthesized 7. enzymes previously made then alter the activity of the cell (think of a virus) folia - folds of the cerebellum chromaffin cells - the cells in the adrenal medulla that secrete epinephrine and norepinephrine; exerts direct control over cells so hormone release can occur very quickly hemispheric lateralization - specialization separation of the hemispheres of the brain; two hemispheres of brain share performance of many functions but also specializes in unique functions language: left, visual spatial skills: right 5 100% Pass Guarantee Katelyn Whitman, All Rights voltage gated channels - open and close in response to changes in membrane potential voltage gated channels - 1. resting membrane potential: negative inside (K+) and positive outside (Na+) (-70mV) 2. depolarization: Na+ channels open; more na + ions outside will diffuse into cell; influx of Na+ cause membrane potential to become more positive(+30mV) 3. repolarization: K+ channels open, Na+ channels closed and then through these channels K+ move out of cell and decreases charge inside (-80mV) 4. refractory period: both K+ and Na+ channels closed; more Na+ in and K+ out of cell (-80mV); antiport for k+ a