An antigen is:
a. a phagocytic cell.
b. used to combat infections.
c. a molecule used by bacteria to destroy antibodies.
d. any molecule that is recognized as foreign by the immune system.
e. produced by a white blood cell.
D
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Match the following items to the correct phrase.
_______1. Facultative anaerobes. _______2. Microaerophiles. _______3. Some species are aerotolerant anaerobes and some species are obligate anaerobes. _______4. Fastidious bacterial pathogens that will grow on chocolate agar but not on blood agar. _______5. Capnophiles. _______6. Acid-fast bacteria. a. Neisseria gonorrhoeae and Campylobacter spp. b. Clostridium spp. c. E. coli, most Staphylococcus and Streptococcus spp. d. Mycobacterium and Nocardia spp. e. Neisseria gonorrhoeae and Haemophilus influenzae
The energy for nearly every organism in almost every ecosystem ultimately comes from _____.
Fill in the blank(s) with the appropriate word(s).
Classification.The five reactions listed below occur during the noncyclic pathway of ATP formation. Use them to respond to the following statements.
A. The final step that occurs during noncyclic ATP formation. B. High-energy phosphate bonds are formed during this process. C. This process releases electrons to replace those lost from chlorophyll in noncyclic ATP formation. D. When light energy is absorbed by a leaf, this will be the first result. E. This results when chlorophyll gains electrons from water molecules.
The main reason certain seeds germinate near the soil surface rather than deep in the soil is
A. they are then more aware of their surroundings. B. they require light to germinate. C. they need additional oxygen. D. they are sensitive to the cold temperatures of the soil. E. they have water deprivation.