Free SAT Biology Practice Test Questions

The SAT (Scholastic Aptitude Test) is the most widely used college admission test.
Streams

• Biology Ecological (Biology-E): Leans more toward biological communities, populations and energy flow
• Biology Molecular (Biology-M): Geared toward biochemistry, cellular structure and processes, such as respiration and photosynthesis.

Exam Pattern

• Questions: 80 Multiple Choice Questions. 60 of the 80 questions are common to both Biology E and M, followed by 20 specialized questions for each section.
• Points: 200–800
• Minutes: 60

Choose the best answer from the five options given below. When you've finished answering as many of the questions as you can, scroll down to the bottom of the page and check your answers by clicking 'Score'. Percentage score will be displayed along with right answers

1. Which of the following describe the physical dimensions for DNA? I. The nitrogen bases are 0.34 nm from one another, moving 5’ to 3’. II. The diameter of the strand is 20 nm. III. The two strands run antiparallel.
I only
II only
III only
I and III
I and II
2. In the development of a frog embryo, Speman’s primary organizer was found to be the
dorsal ectoderm
notochord
neural tube
dorsal lip of the blastopore
archenteron
3. A colorblind man married a woman who wasn’t colorblind, but her father had been. What is the possibility that their first child will be a colorblind girl?
0 percent
25 percent
50 percent
75 percent
100 percent
4. The undershoot during an action potential is the result of
the sodium gates being closed and the potassium gate closed.
one of the sodium gates being open, one closed, and the potassium gate open.
the sodium gates being closed and the potassium gate open.
the sodium gates being open and the potassium gate closed.
the sodium gates being open and the potassium gate open.
5. A man with type O positive blood married a woman with type B negative blood. What is (are) the types of blood that their children can have?
B positive
O positive
B negative and B positive
O negative and O positive
B negative and positive and O negative and positive
6. Carbon dioxide that is leaving the body is carried in I. the plasma. II. erythrocytes. III. hemoglobin molecules.
I only
II only
III only
I and II
I, II, and III
7. People who have an extra X chromosome could have gotten it through
transposition
nondisjunction
crossing over
transduction
all of the above
8. The HIV virus infects mostly
complement cells
red blood cells
T-helper cells
T-killer cells
all of the above
9. Blood entering the dorsal aorta has most recently been in the
right atria
right ventricle
left atria
left ventricle
pulmonary vein
10. The function of ATP in voluntary muscle movement is to supply the energy for
myosin to bind to actin
myosin to become separated from actin.
tropomyosin to bind to troponin.
tropomyosin to become separated from troponin.
tropomyosin to become separated from actin.
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