The first line of defense against foreign invaders is ____
a. adaptive immunity
b. the immune system
c. B and T cell activity
d. physical and chemical barriers
e. antibody production
ANSWER: d
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If a region of DNA contained numerous mismatches due to a modifying agent that caused methylation of guanine, which of the following mutagens is most likely the cause?
A. Ionizing energy such as gamma radiation B. An intercalating agent such as acridine orange C. A DNA modifier such as an alkylating agent D. A deaminating base such as nitrous oxide
Explain why epithelial cells are the source of 80% to 90% of all cancers. Then list at least two types of epithelial cells, and at least four types of cancer for which they are the source
What will be an ideal response?
Which major regions compose the contemporary vertebrate brain?
A. rhombencephalon and prosencephalon only B. mesencephalon and rhombencephalon only C. prosencephalon and metencephalon only D. metencephalon, rhombencephalon, and prosencephalon E. rhombencephalon, mesencephalon, and prosencephalon
What does "light pollution" refer to?
a. diminished natural lighting b. rapid proliferation of artificial lighting c. rapid proliferation of natural lighting d. diminished artificial lighting