An explanation the function of a cell wall and a central vacuole (2) An explanation of why animal cells do not need these organelles

Answer 1

Function of a Cell Wall

The cell wall is a rigid outer layer found in plant cells, fungi, bacteria, and some protists. Its primary functions include:

1. Structural Support and Protection: The cell wall provides rigidity and strength, helping maintain the shape of the cell and protecting it from mechanical stress and external pathogens.
2. Regulation of Water Intake: The cell wall helps control water uptake by creating a pressure potential in conjunction with the central vacuole, which can prevent excess water influx that might cause the cell to burst.

Function of a Central Vacuole

The central vacuole is a large, membrane-bound organelle found primarily in plant cells. Its main functions include:

1. Storage: The central vacuole stores nutrients, waste products, and other substances, which can be essential for the cell’s metabolic processes and overall growth.
2. Turgor Pressure Maintenance: The vacuole helps maintain turgor pressure against the cell wall, critical for maintaining the structural integrity of plant cells and supporting the plant as a whole.

Why Animal Cells Do Not Need These Organelles

Animal cells do not require a cell wall and a central vacuole for several reasons:

1. Lack of Rigid Structure Requirement: Animal cells have flexible plasma membranes rather than rigid cell walls. This flexibility allows them to adopt various shapes and enables movement, as many animal cells are involved in different types of mobility, such as muscle contraction and blood flow.

2. Different Mechanisms for Maintaining Shape and Volume: Animal cells rely on a cytoskeleton, composed of microfilaments and microtubules, to provide structural support and maintain shape. Additionally, animal cells regulate their internal environment and osmotic balance through other means, like ion transport and the presence of various organelles, which makes a central vacuole unnecessary for osmoregulation.

In summary, the absence of a cell wall and a central vacuole in animal cells is due to their structural and functional adaptations that align with their specific roles in multicellular organisms.