<span>LD
means lethal dose. LD50 is the amount of a material, administered at once to
cause the death of half (50%) of a group of test organisms. A test which shows that LD50 of a certain
chemical is 20 mg per kg means that 20 milligrams of that chemical for every 1
kilogram body weight of the test animal when administered in one dose, causes
the death of 50% of the test group.</span>
The effect that malnutrition have on the fetus during critical development in pregnancy is that the impairment of the development of an organ is irreversible. Maternal malnutrition can adversely affect the division and replication of cells in the embryo at this stage, impairing its development. The effects of malnutrition during critical periods of pregnancy are seen in defects of the nervous system of the embryo, poor dental health among other effects.
Answer:
In biology, the smallest unit that can live on its own and that makes up all living organisms and the tissues of the body. A cell has three main parts: the cell membrane, the nucleus, and the cytoplasm. ... Parts of a cell. A cell is surrounded by a membrane, which has receptors on the surface.
The heart consists of four chambers in which blood flows. Blood enters the right atrium and passes through the right ventricle. The right ventricle pumps the blood to the lungs where it becomes oxygenated.
Explanation:
Pretty sure it's D. Mercury
