While hiking, you must push aside thick branches that are near your face. One of them rips the skin on your arm and you begin to bleed from the cut. Which of the following plays an important role in initially protecting you from infection?

A) nonspecific antibodies
B) barriers such as dead skin cells and mucus because they are part of the innate immune system
C) increased production of certain hormones and changes in microcirculation
D) memory cells because they are part of the adaptive immune system


Answer: B

Biology & Microbiology

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What is the role of the MADS box genes in plants?

A) The MADS box inhibits compound leaf formation. B) The MADS box acts as a transcription factor that regulates flower formation. C) The MADS box genes allow for hypocotyl elongation. D) The MADS box genes control the organization of cell polarity in the apical meristem. E) The MADS box genes control the timing of germination.

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In invertebrates, such as flatworms, groups of neurons called ____ perform common functions

a. nerve cords b. ganglia c. brains d. nerve nets e. radially symmetrical

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All of the following are true of hemoglobin

EXCEPT

a. it is found in the blood of all vertebrates. b. it increases blood's oxygen carrying capacity. c. it is a protein. d. it will reversibly bind oxygen. e. it releases oxygen in regions where oxygen concentration is high

Biology & Microbiology

Fats and carbohydrates serve as the primary fuels to produce energy.

a. true b. false

Biology & Microbiology