Question

State three main functions of cell membrane and nucleus

Answer 1

Biological membranes have three primary functions: (1) they keep toxic substances out of the cell; (2) they contain receptors and channels that allow specific molecules, such as ions, nutrients, wastes, and metabolic products, that mediate cellular and extracellular activities to pass between organelles and between the organelles and between the cell and the outside environment; and (3) they separate vital but incompatible metabolic processes conducted within organelles.
The nucleus regulates all cell activity. It does this by controlling the enzymes present. The chromatin is composed of DNA. DNA contains the information for the production of proteins. This information is encoded in the 4 DNA bases. Adenine, thymine, cytocine, and guanine. The specific sequence of these bases tells the cell what order to put the amino acids.
There are three processes that enable the cell to manufacture protein: 
Replication allows the nucleus to make exact copies of its DNA 
Transcription allows the cell to make RNA working copies of its DNA 
In translation the Messenger RNA is used to line up amino acids into a protein molecule

Answer 2

Answer:

Functions Of Cell Membrane

1. It allows movement of substances both inward and outward.

2. It provides shape to the cell .

3.It protects the cell .

Functions of Nucleus

1. It controls all the metabolic activities of the cell .

2. It is responsible for cell division.

3. It helps in inheritance of characters from parents to the children .