Answer:
Phospholipid bilayer.
Explanation:
The plasma membrane (also known as the cell membrane or cytoplasmic membrane) is defined as a biological membrane that separates the interiors of a cell from its external environment.
The plasma membrane has a function that protects the cell from its external environment, mediates cellular transport, and transmits cellular signals.
It is composed of a lipids bilayer (phospholipids and cholesterol), (phospholipid is a lipid made of glycerol, two fatty acid tails, and a phosphate-linked head group) with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules which hence, regulates the movement of substances in and out of cells. Plasma membranes is very flexible in order to allow cells change form example, red blood cells change shape as they pass through narrow capillaries.
The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the "Cambrian Explosion," because of the relatively short time over which this diversity of forms appears
B. An ecosystem in which plant roots are submerged during parts of the years
Answer:
C: autocrine
Explanation:
There are three types of hormones according to where their target cells are.
- Endocrine: Their target cells are distributed far and they travel via blood to reach the target cells.
- Paracrine: Their target cells are often their neighbors so they often diffuse to reach them
- Autocrine: Their secretion acts on themselves. Hence they are their own targets.
Hydrogen and hydroxide ions
