Question

Size and shape of the cell depend upon their function

Answer 1

Cells are the building blocks of life – all living organisms are made up of them. Books often show a single ‘typical’ example of a plant cell or an animal cell, but in reality, the shapes of cells can vary widely. Animal cells in particular come in all kinds of shapes and sizes. Plant cell shapes tend to be quite similar to each other because of their rigid cell wall.

Cells are of different shape,size and structure according to the function they needs to perform. So, if all the cells will be of same shape and size , it will be very difficult for multicellular animals including humans to adapt better to the environment and survive. also, the division of labour among cells will be lost leading to difficulties in survival.

Cells have different shapes because they do different things. Each cell type has its own role to play in helping our bodies to work properly, and their shapes help them carry out these roles effectively. The following cell types all have unusual shapes that are important for their function.

Neurons are cells in the brain and nervous system. Their job is to carry electrical messages all the way from the brain to the rest of the body and back (almost like electrical wire), so they are very long, thin, branched cells. They also need to connect with other neurons to form communication networks, so they have many long branches.
photoreceptor cells (rods and cones) are cells in the eye that detect light.
Red blood cells are shaped like a doughnut to carry more hemoglobin, and to fit through small spaces, your epithelia of your gut have many small finger-like extensions to increase surface area to absorb the nutrients from digestion.
Immune cells are cells that respond when the body is infected (by a bacterium, for instance). To do their job, they need to be able to change shape. For instance, lymphocytes may need to move through body tissue to get to the site of infection, so they change their shape to squeeze past tightly packed tissue cells. Some immune cells (such as neutrophils) engulf bacteria and viruses, so they need to change their shape to ‘swallow’ them.