1) if the resting axon’s membrane becomes more permeable to potassium ions,
a) the inside of the membrane will become more positively charged.
b) the membrane will depolarize more rapidly.
c) it will take a stimulus of larger magnitude to initiate an action potential.
d) the hyperpolarization at the end of the action potential will not occur.
2) during gestation, powerful uterine contractions are suppressed by elevated levels of
a) progesterone.
b) estrogen.
c) oxytocin.
d) prostaglandins.
e) all of the answers are correct.
3) in order for blood to enter the heart,
a) the atria must be in diastole.
b) the pressure in the atria must be lower than in the veins.
c) the av valves must be open.
d) the atria must not only be at rest but the atrial pressure must be lower than the veins.
e) all of the answers are correct.
4) blood flow to a tissue will increase if the
a) level of oxygen at the tissue increases.
b) level of carbon dioxide at the tissue increases.
c) ph rises.
d) vessels constrict.
e) all of the answers are correct.
5) match each product with the cell or region that secretes or contains it.
a. enzymes
b. hcl
c. hco3-
d. mucus
e. more than one of these
goblet cells
6) nitroglycerine is a medication taken by people who experience chest pain known as
angina. one of the major side effects of the medication is that the patient will notice a
severe headache. what causes this side effect?
7) increased blood volume ________ blood pressure.
a) increases
b) decreases
c) has no effect on
8) blood pressure and cardiac output can be altered according to
a) body temperature.
b) emotional responses.
c) blood oxygen levels.
d) body temperature and emotional responses.
e) body temperature, emotional responses, and blood oxygen levels.
9) when a neuron changes its ion permeability from the resting state,
a) a variety of gated ion channels may open or close.
b) na+ channels may open, allowing na+ to enter the cell.
c) k+ channels must open, allowing k+ to enter the cell.
d) only a variety of gated ion channels may open or close and na+ channels may open,
allowing na+ to enter the cell.
e) a variety of gated ion channels may open or close, na+ channels may open, allowing
na+ to enter the cell, and k+ channels must open, allowing k+ to enter the cell.
10) explain how these statements differ, and identify which one(s) is/are correct.
explain what is wrong with each incorrect statement. explain when chemical reactions
continue and when they stop.
a. a chemical reaction proceeds until the enzyme molecules are all consumed.
b. a chemical reaction proceeds until the substrate molecules are all consumed.
c. a chemical reaction proceeds until equilibrium is established.
d. a chemical reaction proceeds until all the product molecules are removed.
11) sally student does not understand the differences between ions, isotopes, and free
radicals. assuming she has learned and understood some basic chemistry, what is the
likely source of her confusion? review the definitions of these terms, then make a table
or flow chart to help her sort this out.
12) a chemical reaction that can proceed in both directions is called a ________.
13) amy is a premed student with a summer job as an animal research technician. one of
her duties is to withdraw blood by syringe from the anterior vena cava of pigs, to be
analyzed for various hormones. during her training she noticed that most blood samples
were very dark in color, but occasionally a sample was bright red. propose an
explanation.
14) the hormones of the anterior pituitary are controlled by trophic hormones from the
________.
15) explain the events leading up to a skeletal muscle twitch, starting with the arrival of
neurotransmitter in the neuromuscular junction.
16) sketch and label a relaxed sarcomere, then draw the same sarcomere in a contracted
state. the myofilaments may be represented as simple lines.