A cline: a. is continuous variation that follows a geographic continuum.
b. is variation that falls into discrete categories.
c. was used to describe human variation as early as the Renaissance.
d. describes the pattern of occurrence of trisomy 18.

The correct answer is - option A is continuous variation that follows a geographic continuum.

Explanation:

A cline is a slow change in the physical and genetic traits of a population or species across a geographical difference or gradient. If a species present in a very large area, there would be some members live on different environmental condition in comparison to others.

By this gradient members of species show continuous variation that follows a geographic continuum. For, example, In a species of warm-blooded animals have large body size in cooler area than in warmer area.

Thus, the correct answer is - option A is continuous variation that follows a geographic continuum.

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?