Answer:
Explanation:
The main function of the plasma membrane is to protect the cell from its surroundings. Made of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules it also regulates the movement of substances in and out of cells. Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. Membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors, which then trigger intracellular responses. Some viruses, such as Human Immunodeficiency Virus (HIV), can intercept these receptors to get into the cells, causing infections.
Answer:
Sunlight is an electromagnetic wave carrying energy that is absorbed by the skin.
Explanation:
Adrenaline
Nicotine is a substance that is addictive in nature commonly
found in cigarette, that affect the nervous system by binding to the receptors
in the brain and other part of the body. Atherosclerosis is the loss of
elasticity or thickens of arteries walls. However, nicotine increases the
release of neurotransmitter adrenaline into the blood which subsequently cause
the development of atherosclerosis.
