How can dominance and expression of alleles explain the differences between these fraternal twins?

Acell in the human nervous system whose primary function is to form myelin and the blood-brain barrier, respond to injury, remove debris, and enhance learning and memory is called a(n) cell.

Nephrons, the functional unit of kidneys, are responsible for formation of urine. the sentences describe situations that are the result of problems in the urine formation process. for the nephron shown below, match each situation to the step in the urine formation process where the problem lies.

Based on the number of offspring they produce at one time organisms are classified into two categories many offspring at once and a few at a time sort the carry sticks based on the category they describe