Question

Why are cell walls absent in animal cells, but necessary for the survival of plant cells?

Answer 1

Animal cells lack a cell wall because they do not need the structural support that plant cells do for upright growth. Plant cells have a rigid cell wall made of cellulose, which aids in providing support and protection, and facilitates the passage of water and nutrients.

Step-by-step explanation:

Why Animal Cells Lack Cell Walls

Animal cells do not have a cell wall because they have different structural requirements than plant cells. Animal cells are typically surrounded by a flexible plasma membrane that allows for the formation of a variety of shapes and for specialized functions like the ability to move. In contrast, plant cells require a cell wall for several reasons. The cell wall is a rigid structure made primarily of cellulose, a polysaccharide composed of glucose units. It provides the necessary support for plants to grow upright and maintain a fixed shape. Moreover, plant cells need this rigidity to withstand the osmotic pressure that could otherwise cause the cell to burst when water enters. In addition to cellulose, the cell wall contains proteins and other polysaccharides that contribute to its function.

Another key difference is the presence of chloroplasts in plant cells, which are necessary for photosynthesis—a process that does not occur in animal cells. The cell wall also contributes to a plant's overall strength and protection, and it allows water and nutrients to move into and out of the cell while maintaining the plant cell's integrity.

Answer 2

Cell walls are absent in animal cells, while they are essential for the survival of plant cells due to fundamental differences in their structure, function, and environmental adaptation.

The primary function of the cell wall in plant cells is to provide structural support and rigidity to the cell. It maintains the shape of plant cells and prevents them from collapsing.

Cell walls act as a protective barrier, shielding plant cells from physical damage and pathogens. The rigid cell wall helps protect against external pressures and environmental stress. The cell wall also plays a crucial role in regulating water balance. It allows plants to resist turgor pressure, which is the pressure exerted by the cell contents against the cell wall. This pressure contributes to cell rigidity and helps prevent wilting.