Central chemoreceptors located in the medulla provide feedback to increase the rate and depth of breathing when they sense: select one: a. decreased levels of oxygen in the blood and an increase in the ph of the cerebrospinal fluid. b. increased levels of oxygen in the blood and a decrease in the ph of the cerebrospinal fluid. c. slight decreases in carbon dioxide and an increase in the ph of the cerebrospinal fluid. d. slight increases in carbon dioxide or a decrease in the ph of the cerebrospinal fluid.

Fan egg cell containing the (n+1) number of chromosomes combines with a sperm cell containing the (n) number of chromosomes, what is the result of this union? a) all future somatic cells of the organism will contain the (2n + 1) number of chromosomes. b) all future somatic cells of the organism will contain the (2n - 1) number of chromosomes. c) only certain somatic cells of the organism will contain the (2n + 1) number of chromosomes. d) all future somatic cells of the organism will contain the normal diploid number of chromosomes.

Which is an example of a decomposer? a. bear b.algae c.grass d.bacteria d bacteria

18. which statement about cancer is true?