Which animal of the Cambrian period is also one of the first animals to exhibit a sense of vision?
a. Cyclomedusa
b. trilobite
c. Dickinsonia
d. Spriggina
b. trilobite
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Examine the figure above. What type of pattern did the human population exhibit through most of its history (prior to the 1700s)?
A. logistic growth
B. exponential growth
C. zero growth (equilbrium)
D. negative growth
All vertebrates have a(n) __________ system of secretory glands and cells. Fill in the blank(s) with the appropriate word(s)
The cortical reaction functions directly in the
A) formation of a fertilization envelope. B) production of a fast block to polyspermy. C) release of hydrolytic enzymes from the sperm cell. D) generation of a nerve-like impulse by the egg cell. E) fusion of egg and sperm nuclei.
Which of the following statements is FALSE?
A) DNA polymerase joins nucleotides in one direction (5' to 3') only. B) The leading strand of DNA is made continuously. C) The lagging strand of DNA is started by an RNA primer. D) DNA replication proceeds in only one direction around the bacterial chromosome. E) Multiple replication forks are possible on a bacterial chromosome.