Answer:
oxygen because that's one of the substance that plants produce.
You can also do this by the process of elimination. Knowing that atrazine impedes the production of substances in plants, we know that it can't be DNA and Phospholipid. Carbon Dioxide is used by plant, not produced; thus, oxygen is the answer.
The two lower chambers of the heat, which recurve blood from the atria and pump it into the arteries
Answer:
Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population.
Infertility is the incapacity to conceive an offspring while erectile dysfunction is the incapacity to get aroused so as to engage in sexual intercourse (mostly in men).
Erectile dysfunction could be caused by stress, cardiovascular diseases, and diabetes. Therefore treating it requires maintaining a healthy lifestyle of nutrition and exercise.
Infertility can be caused by disorders of reproductive organs such as endometriosis and occlusion in the tubes. This can be treated by assisted reproduction (IVF), corrective surgery and education.
