Modern invertebrates first appear in the fossil record during the

A) Cambrian period.
B) Silurian period.
C) Precambrian era.
D) cyanobacteria.
E) Devonian period.


C

Biology & Microbiology

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In your Drosophila laboratory, you find a larva that is missing segments Lb, T1, T2, and T3. This larva probably has a mutation in a ___________ gene.

A. pair-rule B. gap C. maternal effect D. segment-polarity E. gap or segment-polarity

Biology & Microbiology

The movement of water across a membrane in response to a gradient of solute concentration is called:

a. salinity. b. osmosis. c. solubility. d. diffusion. e. pressure.

Biology & Microbiology

Which of the following is not an assumption of the Hardy-Weinberg principle?

a. no mutation b. no migration c. small population size d. random mating e. no selection

Biology & Microbiology

To which group of plants are insect pollinators most important?

A) gymnosperms B) angiosperms C) mosses D) ferns

Biology & Microbiology