Answer:E. Down-regulation
Explanation:Cells typically up or down regulate depending on the concentration of a hormone levels. When there is a excessive concentration of a hormone in the blood stream, the cell decreases the number of receptors reducing the interaction with that hormone, Also, when there is excessive hormone reduction, the target cells activate to increase their number of receptors.
Down regulation occurs by the the deactivating or degrading of target cells to reduce the number of receptors due to their sensitivity to a particular excess hormone.
1) The antibodies destroy the antigen (pathogen) which is then swallowed and digested by macrophages.
2) White blood cells can produce antitoxins which destroy the toxins that are otherwise known as poison.
It is very important to control the conditions of an experiment because FAILURE TO DO THIS WILL MAKE THE RESULTS OF THE EXPERIMENT INVALID.
A controlled experiment refers to an experiment that is conducted under controlled conditions. Conducting experiments under controlled conditions helps scientists to minimize the changes in all other variables with the exception of the ones been tested.
Answer:
D
Explanation:
With a higher surface area the cell is able to produce more ATP
Answer: B. Pathways by which matter is transferred between organisms and the environment
Explanation:
Biogeochemical cycles can be define as cycles which involves the natural pathways by which inorganic and organic matter is transferred within the living organisms and the environment.
The essential elements such as water, carbon, phosphorous, nitrogen and oxygen are transferred among the various spheres of the earth like atmosphere, biosphere, lithosphere and others which forms the integral part of the non-physical environment.