| PART A -
Answer all 35 questions in this part. (35)
Directions (l-35): For each statement or question, write on the separate
sheet the number of the word or expression that, of those given,
the statement or answers the question.
1 Which statement describes the best procedure to determine if a vaccine
for a disease in a certain bird species is effective?
(1) Vaccinate 100 birds and expose all 100 to the disease.
(2) Vaccinate 100 birds and expose only 50 of them to the disease.
(3) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose all 100 to the disease.
(4) Vaccinate 50 birds, do not vaccinate 50 other birds, and expose only
the vaccinated birds to the disease.
2 Scientists have cloned sheep but have not yet cloned a human. The best
explanation for this situation is that
(1) the technology to clone humans has not been explored
(2) human reproduction is very different from that of other mammals
(3) there are many ethical problems involved in cloning humans
(4) cloning humans would take too long
3 In an ecosystem, what happens to the atoms of certain chemical elements
such as carbon, oxygen, and nitrogen?
(1) They move into and out of living systems.
(2) They are never found in living systems.
(3) They move out of living systems and never return.
(4) They move into living systems and remain there.
4 The main function of the human digestive system is to
(1) rid the body of cellular waste materials
(2) process organic molecules so they can enter
(3) break down glucose in order to release energy
(4) change amino acids into proteins and carbohydrates
5 The normal sodium level in human blood is 135 mEq/L. If a blood test
taken immediately after a meal reveals a sodium level of 150 mEq/L, what
will most likely result?
(1) Antibody production will increase.
(2) The person will move to an ecosystem with a lower sodium level.
(3) The nutritional relationships between humans and other organisms
(4) An adjustment within the human body will be made to restore