Blood cells are produced in which system?
a. circulatory system
b. immune system
c. skeletal system
d. endocrine system
user:
heart disease includes all of the following risk factors except
a. high blood pressure
b. high cholesterol levels
c. cigarette smoking
d. regular exercise

What would most likely happen if green plants were exposed to longer days of sunlight? a. the mitochondria would produce less energy . b. the chloroplasts would produce more energy. c. the cell wall would become thicker. d. the vacuoles would quickly shrink.b. the chloroplasts would produce more energy.