Question

Plant cells differ from animal cells in having (a) cell wall (b) plastids (c) a large.central vacuole (d) all of these.

Short answer

Plant cells differ from animal cells in having all of the mentioned features: a cell wall, plastids, and a large central vacuole. So, the correct answer is (d) all of these.

Step-by-step solution

Identify Unique Plant Cell Features

To solve this exercise, first recall the distinct features that differentiate plant cells from animal cells. These may include structures like a rigid cell wall, chlorophyll-containing plastids, and a large central vacuole for storage and maintaining cell rigidity.

Match Features to Options

Compare each feature mentioned in the options (a, b, c) to the list of unique plant cell features identified in Step 1. Determine if each option is present exclusively in plant cells and not in animal cells.

Determine the Correct Answer

After analyzing all options individually, recognize that each of them (cell wall, plastids, and a large central vacuole) is indeed a feature that distinguishes plant cells from animal cells. Therefore, the correct answer includes all the given features.

Key concepts

Cell Wall

Plants have some distinctive features that set them apart from other living organisms, particularly animal cells. One such defining feature is the cell wall. Unlike animal cells, that only have a cell membrane, plant cells have an additional protective layer. The cell wall is made primarily of cellulose, a sturdy carbohydrate that provides support and structure.

The wall not only gives the cell its shape but also helps in defending against mechanical stress and pathogens. Its rigidity allows plants to stand upright and grow vertically, defying gravity. The existence of the cell wall is a fundamental characteristic that is key to plant cells' ability to thrive in a variety of environments.

Plastids

Another remarkable feature of plant cells is their plastids. Plastids are a group of membrane-bound organelles that are involved in the manufacture and storage of important chemical compounds used by the cell. One of the most well-known plastids are chloroplasts, which contain the green pigment chlorophyll. This is crucial for photosynthesis, the process by which plants convert light energy into chemical energy.

Plastids can also store pigments that contribute to the color of flowers, fruits, and leaves, as well as starches, lipids, and proteins. They are like tiny factories and storage units within plant cells that are not found in animal cells, serving functions vital for the plant's survival and functionality.

Central Vacuole

The central vacuole is a distinguishing component of plant cells. Occupying up to 90% of a cell's volume, this large, membrane-bound sac is essential for a variety of cell functions. It serves as a storage space for nutrients, waste products, and pigments, and also helps in maintaining turgor pressure against the cell wall.

Through this pressure, the vacuole supports the plant's overall structure and rigidity. The central vacuole also plays a role in cell growth by expanding and allowing cells to become larger without necessarily creating new cellular material. Animal cells, in contrast, have much smaller vacuoles, which serve similar storage functions but do not contribute to cell rigidity or growth in the same way.

Differences Between Plant and Animal Cells

Understanding the differences between plant and animal cells is vital for grasping key biological concepts. Plant cells are remarkable as they can synthesize their own food through photosynthesis thanks to chloroplasts, which animal cells cannot. Another key difference lies in plant cells having a cell wall, providing them with structural support for growth. This feature enables plants to stand upright and reach for light, essential for their survival.

Animal cells, conversely, have greater flexibility and can change shape owing to the absence of a cell wall, which is instrumental in enabling movement and a broader range of interactions with their environment. This adaptability assists animals in responding to stimuli with more precision, enabling various functions that plants, due to their rigid cell walls, do not exhibit. Both cell types have evolved to have unique strengths and specialized roles based on these differences, showcasing nature’s diversity.