4. Give functions.
a. Plasma membrane
b. Cytoplasm
c. Lysosome
d. Vacuole
e. Nucleus
Answers
Plasma membrane
It is a microscopic membrane of lipids and proteins which forms the external boundary of the cytoplasm of a cell or encloses a vacuole, and regulates the passage of molecules in and out of the cytoplasm.
Cytoplasm
Cytoplasm is the jelly like fluid substance around the cell body. Cytoplasm contains molecules such as enzymes for breaking down waste and also aid in metabolic activities.
Lysosome
Lysosomes are known as the "suicide bags of cell" as they helps in destroying the damaged cells. They contains digestive enzymes that digest the waste cell or organelles, engulf viruses
or bacteria and brings back immunity to the cell.
Vacuole
Vacuoles are membrane-bound sacs within the cytoplasm of a cell that function in several different ways. In mature plant cells, vacuoles tend to be very large and are extremely important in providing structural support, as well as serving functions such as storage, waste disposal, protection, and growth.
Nucleus
The main function of the cell nucleus is to control gene expression and mediate the replication of DNA during the cell cycle. The nucleus is an organelle found in eukaryotic cells. Inside its fully enclosed nuclear membrane, it contains the majority of the cell's genetic material.
Answer:
a. Functions of the plasma membrane:
It gives shape and support to the cell.
It acts as a mechanical barrier to protect the internal contents of the cell.
It separates the contents of the cell from its surrounding medium.
It performs physical activities such as diffusion and osmosis.
b. Functions of cytoplasm:
It is the medium for all cellular chemical reactions.
It is a medium in which the organelles remain suspended.
It helps in the movement of the different cellular elements.
c. Functions of lysosomes:
Lysosomes destroy foreign materials that enter the cell.
Dead and worn-out organelles are removed by lysosomes.
Cells are autolysed by lysosomes, and their contents are released within the cell.
d. Functions of vacuoles:
The main function of vacuoles is to store food in a cell.
They also help in storing and expelling wastes and toxic by products of metabolic reactions.
They help in maintaining the turgidity and rigidity of a cell.
e. Functions of nucleus:
It is the control centre of a cell as it controls all the activities of the cell.
It also contains gene-containing chromosomes which are the units of inheritance in an organism.