Overview

Animal and plant cells not only differ in their structure, function, and mode of nutrition but also in how they reproduce, specialize, and organize into complex structures.

Cell Division

Though both plant and animal cells divide by mitosis (for non-gametic cells) and meiosis (for gametic cells), they differ in the specifics of this process. Unlike animal cells, plant cells lack centrosomes — an organelle responsible for organizing the spindle fibers and segregating the chromosomes during cell division. Instead, they have a microtubule-organizing center (MTOC) that helps the self-assembly of the tubules forming the spindle. Cytokinesis in plant cells is achieved by forming a cell plate, which develops from the center of the cell to the periphery. However, in the flexible animal cells, the contractile ring causes the cell membrane to contract and pinch off two daughter cells.

Cellular Organization

Plant cells typically have a fixed shape, mostly rectangular, due to the rigid cell wall primarily made of cellulose. Therefore, tissue organization in plants is simple, and intercellular communication and exchange of molecules occur via junctions called plasmodesmata. Animal cells are usually smaller and not as rigid due to the absence of a cell wall. This flexibility allows these cells to take up many different shapes and forms. Their tissue organization can be highly complex, with various junctions and channels facilitating intercellular communication. 

Cell Specialization

While both animal and plant cells can specialize into different cell types, the specialization spectrum is relatively limited in plant cells. The primary cell types in plants include the parenchyma, sclerenchyma, and collenchyma, with a few special cells such as xylem, phloem, and root hair cells. On the other hand, animal cells have a diverse spectrum of structure and function ranging from the round, biconcave red blood cells that transport oxygen to the highly branched, star-shaped nerve cells that relay electrical signals.

Procedure

Both plant and animal cells are eukaryotic. Their cytoplasm contains membrane-bound organelles, such as the nucleus, endoplasmic reticulum, and mitochondria.

However, they differ in their structure, mode of nutrition, and functions.

Plant cells can range from 10 to 100 microns in size and are primarily supported by a cell wall and a large central vacuole. The water-filled vacuole stores nutrients and helps maintain turgor pressure to support the cell shape.

In contrast, animal cells are smaller, measuring only 10 to 30 microns in size. They lack a cell wall and have numerous small vacuoles. 

Animal cells are supported internally by a network of protein filaments called the cytoskeleton.

Both these cell types primarily differ in their nutritional requirements.

While plant cells contain plastids, such as chloroplasts, that enable them to carry out photosynthesis and make their food; animal cells can only ingest nutrients from the outside.

In animal cells, membrane-bound organelles called lysosomes function as sites for the breakdown of macromolecules. However, these organelles are rarely observed in plant cells.

Whereas plant cells lack cilia and flagella, animal cells often have such cellular appendages that help in motility.