What happens in the human body as heart rate is increasing?

Astructure that is found in a plant cell and not in an animal cell is a ? central vacuole mitochondrion nucleus ribosome

With regard to enzymes, key is to lock as a) substrate is to activation energy eliminate b) product is to substrate. c) enzyme is to active site. d) substrate is to active site.

Need asap plz hurry im being timed when a body cell divides through the process of mitosis, the chromosomes in the daughter cells a. represent only the healthiest chromosomes from the parent cell. b. represent only half of the chromosomes in the parent cell. c. are identical to the chromosomes of the parent cell. d. are formed when chromosomes from the parent cell cross over.