Sickle cell disease is caused by a
a. change in one dna base.
b. change in the size of a chromosome.
c. change in two genes.
d. change in the number of chromosomes in a cell.

Trustworthy health-related websites should be frequently reviewed by medical professionals, even if the content doesn't change. select the best answer from the choices provided. t f

Brad was almost hit by a speeding truck as he crossed the street. his heart began to race, and he felt extremely afraid as he jumped out of the way in just enough time to avoid the truck. a psychologist who supports the theory of emotion would claim that based on the arousal brad experienced, he appraised the situation and then labeled his racing heart as fear. a. james-lange b. cannon-bard c. schachter two-factor d. evolutionary

Epidemiology and health expenditure