All plants and animals are made up of living cells, which are basic units of life. However, there are distinct differences between the cells of plants and animals like in
- Size
- Cell wall
- Cell organelles
- Food procurement
- Waste management
- Moveability etc.
Plants are fixed at one location throughout life, which leads to exposure to harsh environments like rainfall, sunlight, and cold.
Further, they cannot escape predators and have to survive within the available resources of water and soil nutrients.
Hence, their cells become adapted to suit the conditions.
Plant cell vs. Animal cell
| Feature | Plant cell | Animal cell |
| Size | Are larger in size comparatively (10 to 100 microns) | Are smaller in size (10 to 30 microns) |
| Shape of cell | Mostly fixed, rigid, and rectangular in shape | Fixed but flexible due to no cell wall, and shapes vary based on the cell types, tissue, and other requirements. |
| Cell wall | It is present, and it gives them rigidity and protections | Cell walls are absent and unnecessary as animals have other means of protection, such as running away to safety. |
| Cell organelles | Most cell organelles are similar, but special ones, like Chloroplasts and amyloplasts, are present. | Chloroplasts are absent except in euglena. Amyloplasts are absent. |
| Cell types | The types of cells few like 1. parenchymal 2. Collenchyma 3. Sclerenchyma 4. Germinal cells | Many cell types as per the animal’s need. 1. Muscle cell 2. Nerve cell 3. Bone cell 4. Secretory cell 5. Epithelial cell 6. ciliary cell 7. Red blood corpuscle 8. Fat cell |
| Dead cells | In plants, dead cells harden with age, and the inner content is lost, while only cell walls thicken and remain part of the body. | Dead cells are destroyed or digested. |
| Vacuoles | A single large vacuole is present | Small but more than one vacuole present |
| Tissue types | Only three major tissues are present in plants: parenchyma, collenchyma, and sclerenchyma. Besides, there is meristem at tips. | Four tissue types are epithelial tissue, connective tissue, muscular tissue, and nervous tissue. |
| Free moving cells | No plant cell is free to move within the body | Blood cells, sperms, and ova in animals move freely in the defined channels. |
| Centrioles | Centrioles help cells to pull apart chromosomes. These are absent | Centrioles present and help to organize spindles to pull chromosomes away |
| Plasmodesmata | Plasmodesmata, i.e., cell bridges connecting the cytoplasm of adjacent cells, present | Plasmodesmata is absent and not necessary. |
| Photosynthesis | Green cells with chloroplast prepare their own food by photosynthesis | Animal cells always depend on others for food. |
However, there are many similarities between plant cells and animal cells, too.
They are both eukaryotic cells and are also similar to a large extent in terms of the cell organelles.
These cells control the organism’s birth, growth, reproduction, and even death.
They differ a lot in terms of physiological function and their role.
Plant cell phases:
Based on their cell phases or life stages.
The early cells are called parenchyma. These cells form tissues in plants and get differentiated to form newly formed tissues. This tissue has great potential to grow.
The next stage of the cells is collenchyma. This collenchyma tissue has no potential to grow but has physiology and a very long life span. It is terminated by the next stage when cells convert to sclerenchyma.
The last stage of plant cell life is sclerenchyma. Sclerenchyma has only dead cells, which are not removed from the plant body. Instead, it is used to give hardness and support to the plant.
This sclerenchyma cell is made hard due to the deposition of a dead substance, namely lignin. It also supports other plant functions by being converted to xylem, phloem, etc. Here, the xylem is a water-conducting channel, and the phloem is a food-conduction channel to the whole plant. Since plants have no circulatory system, these channels serve the purpose.
So, the trend in plant cell life is that parenchyma converts to collenchyma, and then they convert to sclerenchyma as they age.
Animal cell phases: Animal cells have no such phases. They are just born, grow, perform normal physiology, and die.
The dead ones are replaced by new cells. Dead cells are removed from the body, unlike in plants.
Animal cells and plant cells are similar to a great extent in terms of structure and physiology.
Plants have small variations like an outer rigid cell wall, chloroplast for synthesizing their food by using sunlight, duct-like cell structures to move water and other essential elements through their large and long bodies, etc.
Xylem is meant for water transport, and phloem is meant for food transport. The hormones that influence their physiology are different from those of animal cells.
Food: In animal cells, the food is supplied by some external source and transported by blood. So, for food, animal cells depend on some source, while most plant cells synthesize their food.
Photosynthesis:
This is a process by which cells synthesize their food to the availability of photosynthetic pigments.
Plant cells, especially of leaves and other green-colored areas, have chloroplasts in them by which they synthesize their food by photosynthesis in the presence of light.
On the other hand, animal cells do not have this pigment and mostly do not synthesize their food. However, few protozoa like euglena have pigments that they use for photosynthesis.
Excretion:
The waste of animal cells is removed from the cell and carried outside the body. The waste is mostly in liquid form and is expelled by some specialized organs like the kidney.
In a plant cell, the waste is stored inside the cell or in the vicinity of the cell. This is then stored as alkaloids or other waste, like in leaves, which wither away during monsoons.
So, the waste is eliminated as part of dead body organs.
Respiration: In both plants and animals, respiration is by mitochondria, and energy is from the combustion of carbohydrates in the presence of oxygen.
Read the article on mitochondria and its characters for more details on respiration.
Multiplication:
Cells in both animals and plants multiply in their number by mitosis or meiosis.
The difference is that mitosis gives rise to two new cells with the same genetic trends as parent cells, while meiosis gives four cells with half of the genetic trait of the parent cell.
Mitosis is for cell replacement, while meiosis is for reproduction.
Cell death:
In plant cells, the cells get lignified with age and lose their internal contents.
This adds strength to the plant, though the cell is dead. In animals, cell death results from apoptosis and necrosis.
Also, read more about animal cell facts.
References:
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