The answer is D, white blood cells.
The main function of white blood cells is to defense the body from bacteria or other pathogens. There's 2 main kinds of white blood cells, lymphocytes and phagocytes. Lymphocytes mainly produce antibodies that can kill bacteria or any pathogens, and phagocytes can ingest the pathogens directly.
Therefore, since the white blood cells can protect our body, they're part of our immune system.
Answer:
All
Explanation:
You would need carbon dioxide to be able to sustain life forms such as plants, warm enough temperatures to allow the development of animals, (because they cannot be frozen), they would, of course, need oxygen to allow anyone to breathe, and finally liquid water to sustain healthy life, because we must hydrate that is necessary for survival.
The statement which is false about the intergumentary system is option D. "Keratin is the pigment responsible for skin color."
Even though the skin color of human beings is affected y different substances, the pigment melanin is responsible for it. Melanin is produced within the skin in cells known as melanocytes and it determines of the skin color of darker-skinned humans.
For instance, the skin color of those who have light skin is determined primary by the bluish-white connective tissue placed beneath the dermis and by the hemoglobin which circulates in the veins of the dermis.
As the population of the hares increase, the coyote population increases as they have more food to eat.
