Cell division is a fundamental process that occurs in both plants and animals. However, the timing and pattern of cell division differ between these two groups of organisms. In plants, cell division occurs continuously throughout their lifespan, while in animals, cell division is limited to a certain age.

Continuous Cell Division in Plants
- In plants, cell division occurs continuously, allowing them to grow and develop throughout their entire lifespan. This means that plant cells can divide at any time, as long as the necessary conditions are met.
- Plant cells have the ability to divide and differentiate into various specialized cell types, allowing for growth in size and the formation of new tissues and organs.
- The meristematic tissues in plants, such as the apical meristem at the tip of the root and shoot, are responsible for continuous cell division. These meristems contain undifferentiated cells that are actively dividing, leading to the production of new cells.
- The newly formed cells from plant cell division can differentiate into different cell types, such as parenchyma, collenchyma, and sclerenchyma cells, contributing to the growth and development of the plant.

Limited Cell Division in Animals
- In contrast to plants, animals have a limited capacity for cell division. Most animal cells undergo a finite number of divisions, and once this limit is reached, they enter a state called senescence or cell cycle arrest.
- The number of cell divisions an animal cell can undergo is determined by factors such as the length of telomeres, which are protective caps at the ends of chromosomes. Telomeres shorten with each cell division, and once they become critically short, the cell can no longer divide.
- This limited cell division in animals is thought to be a mechanism to prevent uncontrolled cell proliferation and maintain tissue and organ function.
- However, some animal cells have the ability to divide throughout an organism's lifespan. For example, stem cells in certain tissues, such as the bone marrow and skin, retain their capacity for division and can replenish damaged or aged cells.

In conclusion, cell division occurs continuously in plants, allowing for growth and development throughout their lifespan. In animals, cell division is limited to a certain age, with most cells undergoing a finite number of divisions. This difference in the pattern of cell division reflects the unique biological characteristics and requirements of plants and animals.