Is a network of flattened membrane sacs and the small, round membrane-coated vesicles that arise from them. the smooth portion of this organelle constructs fatty acids and phospholipids, which are needed to produce membranes. the rough portion of this organelle is covered with ribosomes, which are small, globular structures composed of rna and protein

Match the types of competition to their descriptions

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.

The human body maintains a temperature of around 98.6 degrees at all times. enzymes are involved in almost every chemical reaction in the body. which of the following describes the connection between these two statements? a. enzymes function best at a specific temperature. b. the body needs to be warm to prevent hypothermia. c. the body is kept relatively warm to prevent too much enzyme action. d. there is no connection between the two statements.