Each DNA double helix has a backbone that consists of alternating ____
a. covalent and ionic bonds
b. nitrogen-containing bases
c. hydrogen bonds
d. sugar and phosphate molecules
e. covalent and hydrogen bonds
ANSWER: d
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_____ is the process in which two groups of organisms speciate in response to each other and at the same time
A. allopatric speciation B. peripatric speciation C. adaptive radiation D. co-speciation E. sympatric speciation
One of the most critical adaptations of the reptiles in relation to their life on land is the evolution of the
A. amniotic egg. B. allantois egg. C. chorionic egg. D. diploid egg. E. swim bladder.
Most photosynthesis in typical C3 angiosperms takes place in the
a. palisade mesophyll b. spongy mesophyll c. epidermis d. pericycle e. vascular bundles
File this one under "confusing plant terminology." Both a plant's stoma and its stroma are important in photosynthesis. What's the difference between stoma and stroma?
a) Stoma is the singular of stomata, the gas exchange pores in the leaf of the plant, while stroma is the fluid that fills the inner space of a chloroplast. b) Stoma is the singular of stomata, the fluid that fills the inner space of a chloroplast, while stroma are the gas exchange pores in the leaf of the plant. c) Stoma is the singular of stomata, the gas exchange pores in the leaf of the plant, while stroma is the disk-like membranous sac in which the light-reactions of photosynthesis take place. d) Stoma refers to the non-sexual cells of a plant, while stroma is the fluid that fills the inner space of a chloroplast. e) Stoma is the fluid that fills the inner space of a chloroplast, while stroma is a stack of disk-like thylakoids.