Chemical analysis indicates that the cell membrane is composed mainly of:

1) proteins and starch
2) proteins and cellulose
3) lipids and starch
4) lipids and proteins

Which of the following statements is true? a. the main cause for speciation is an increase in gene flow. b. organisms that reproduce asexually are not considered part of a species. c. on a tree of life diagram, speciation is shown by the merging of two different lineages. d.the size of the geographic area inhabited by a population can cause speciation.

Out of the seven main animal groups (fish, mammals, birds, insects, reptiles, amphibians, and arachnids), how many contain members with internal backbones? a. 5 b. 3 c. 7 d. 1

The buildup of sediments where a river empties into a slow-moving or nonmoving body of water is known as a/an