Answer:
Cancer is caused by accumulated damage to genes. Such changes may be due to chance or to exposure to a cancer causing substance. The substances that cause cancer are called carcinogens. A carcinogen may be a chemical substance, such as certain molecules in tobacco smoke.
Explanation:
Answer:
There, ecosystem services are grouped into four broad categories: provisioning, such as the production of food and water; regulating, such as the control of climate and disease; supporting, such as nutrient cycles and oxygen production; and cultural, such as spiritual and recreational benefits.
Explanation:
AIDS
Asexual reproduction means that the cell has "cloned" itself, and will therefore have the same number of chromosomes as its daughter, thus option B is correct.
Schwann cells produce the protective covering around certain nerve cells called myelin.
It's most commonly found covering motor neurons in vertebrate animals. Myelin-covered neurons have a faster conduction velocity.