Question

Animal cell is limited by
A. Plasma membrane
B. Cell membrane
C. Basement membrane
D. Both a and b

Answer 1

Hint: Animal cell is typically a eukaryotic cell.
 It consists of plasma membrane, membrane bound nucleus and cytoplasm which contains mitochondria, small multiple vacuoles, endoplasmic reticulum.

Complete answer: In order to solve this question we need to know about animal cell.
Cell is a basic structural and functional unit of life
Two main types of cells are:
1. Plant cell
2. Animal cell
Organism which contains a single cell is known as a unicellular organism.
Organism which contains many cells is known as multicellular organisms.
According to this question, Animal cells are limited by plasma membranes.
Plasma membrane or cell membrane is the double layer outermost membrane of the animal cell which protects the cell from external environment
And separate the interior of the cell from the outer environment.
Plasma membrane is made up of lipid bilayer.
Lipids are arranged in such a way that the polar head faces towards the outer part and the hydrophobic tail towards the inner part.
It consists of proteins and carbohydrates also.
Two types of protein are found:
1. Integral protein
2. Peripheral protein.
 Integral protein lies on the surface of the layer, whereas peripheral protein is buried completely in the layer.
Plasma membrane helps in movement of substances in and out of the cell.
 It helps in cell signaling.

So, the correct option is option D both a and b.

Note: cell wall is the outermost layer of the cell which is found on the plant cell
Plant cell consists of a cell wall and plasma membrane. Cell wall is placed outer to the plasma membrane.
It is tough, flexible in nature but sometime may be rigid. It protects the cell from the outer environment. It also acts as a filtrating mechanism.