WSU BIO 106 PRACTICE EXAM

WSU BIO 106 PRACTICE EXAM 4 The neuron: a) Has high internal concentrations of Na+ b) Generally has a simple shape with low surface area c) has dendrites that send signals to other neurons d) Has vesicles filled with neurotransmitter e) Has a membrane potential that is +50 mV at rest - d Which of the following is true about neurons: a) Intracellular fluid (inside the cell) - primary cation is Ca+, Na+ is low b) Extracellular fluid (outside the cell) - primary cation is K+, Na+ is low c) Intracellular fluid has high pH d) Extracellular fluid has high Cle) Extracellular fluid has high large anions (A-) - d the membrane potential a) is an electrical potential between the capillaries and the outside of the body b) is usually between +50 to +100 mV c) results from Ca++ leakage out of the cell d) is usually negative inside the cell e) is the potential for membranes to transport oxygen - d Which of the following occurs when the membrane is at rest a) large anions [A-] leak out of the cell b) voltage gated ion channels (Na+ and K+) are closed c) voltage gated ion channels are open d) K+ is attracted to positive charge outside the cell e) Na+ is attracted to positive charge inside the cell - b In the neuron during action potentials: a) The gradient between extracellular and intracellular fluid favors loss of Na+ from the cell b) K+ will flow out of the cell when the voltage gated potassium channel is open. c) Na+ will flow out of the cell when the voltage gated sodium channel is open d) The membrane starts at -70 mV then drops to -100 mV for several seconds - b In the neuron during the repolarizing part of the action potential (returning to resting state): a) Cl- channels open and stay open b) Na+ channels are open c) K+ channels are open d) membrane potential is becoming more positive e) membrane potential rises to +1000 mV - c In the neuron following the threshold of stimulus: a) The membrane potential stays at 0 mV b) Na+ flows into the cell resulting in a rapid change in membrane potential c) The membrane potential returns to -70 mV d) Na+ flows out of the cell e) Clflows into the cell - b The Na-K ATPase a) pumps 3 Na+ into the cell and 2 K+ out of the cell using ATP b) prevents the action potential c) is blocked by tetrodotoxin d) maintains high K+ inside the cell and high Na+ outside the cell - d It takes several milliseconds for action potentials to be generated.It takes 200 milliseconds for humans to react to a stimulus. Which of the following is true about human nervous responses: a) They are faster than electrical signals in computers b) Baseball batters should be able to hit fast pitches 100% of the time. c) It is extremely difficult to hit a 90 mph fastball because it is only takes 400 milliseconds for the ball to reach home plate d) Pro baseball batters can hit women's softball pitches 100% of the time - c Which of the following is a starch polymer made from many glucose molecules: a) Insulin b) Substance P c) Glycogen d) Adrenalin e) Periplanone - c