What is true about the heterozygous sickle-cell (HbA HbS) condition?
A: sickle-cell anemia is not expressed
B: sickle-cell anemia is expressed under conditions of oxygen deficiency
C: sickle-cell anemia is apparent in men
D: none of the above

Epinephrine is a hormone released from the adrenal gland of the body, most often in a stressful situation. it is known as the "fight-or-flight" hormone. one way that it causes a response in the body is to activate receptors on muscle cells. where are these cellular receptors located? a. on the cell membrane b. in the nucleus c. on the cell wall d. around the mitochondria

The negative impacts of nonnative species generally outweigh the positive impacts

What is the statement plant growth is affected by the color light