The plasma membrane is the boundary between the cell and its environment. It regulates what enters and exits the cell. Cells must maintain an appropriate amount of molecules to function inside them. They must also have a way to keep things out or to allow things to enter. This is the job of the plasma membrane. The plasma membrane is like the guard at a gated community. The guard must inspect those who enter and those who leave to make sure that only the people and things needed in the community are there.
The cell membrane is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out. It also serves as a base of attachment for the cytoskeleton in some organisms and the cell wall in others. Thus the cell membrane also serves to help support the cell and help maintain its shape.
The biosphere. This is the layer that contains all life on the planet.
Biosphere- protect habitats
Atmosphere- reduce auto emissions
Hydrosphere- reduce,reuse,recycle
Geosphere- limit fertilizer
Answer:There are 11 nonessential amino acids.
Explanation:amino acids are monomers of proteins.proteins are made up of carbon,hydrogen, oxygen and nitrogen.there are 20 amino acids found in proteins.
Plants cam produce all the amino acids they need but animals cannot.
Essential amino acids are those that animals cannot produce by themselves and so need to obtain from their diet.there are 9 in numbers.
Non-essential amino acids are produced by the animals.they are not necessarily non-essential as the name indicates.they are 11 in numbers.
The answer is the first one.
