Importance of Cell Differentiation

Discuss the importance of cell differentiation.

There are a variety of ways in which cells can be differentiated. A cell can be separated depending on its ability to exist alone or in a group. Single cell (unicellular) organism functions by itself while a multi-cellular organism is made up of a group of cells that are interdependent to meet their function. These specialized cells make up plant cells like palisade cells, xylem, phloem and stomata whose structure is vital for the occurrence of photosynthesis, making plants the primary producers. They also make up the consumers of plants i.e. the animals. Egg and sperm cells enable the production of offspring in humans. In humans coordination is possible due to specialized cells in neurons and neurotransmitters controlling impulses through the muscles. Retinal cells in the eye are also very vital in enabling various organisms to see accurately in order to survive.

The cell is generally classified into two types: eukaryotes and prokaryotes. Prokaryotes are single cell organisms that do not have a nucleus or any other membrane bound organelle. They have no nuclear membrane and hence the genetic material is dispersed in the cytoplasm. They usually have flagella which enables them to move. Prokaryotes reproduce asexually by binary fission which is the splitting of two cells in half, producing two daughter cells which are identical copies of the cell. Prokaryotes have an enfolded plasma membrane called mesosome which aids in DNA replication. They also have an outer surface made of a slimy layer which protects it from dehydration and antibodies that might attempt to kill it. In contrast, the eukaryotic cells are complex with many membrane bound organelles. Some eukaryotes have chloroplast which traps sunlight for use in photosynthesis. Most eukaryotes contain Golgi body which synthesizes glycoprotein and removes waste products from the cell. They also contain mitochondria which produces ATP which provides energy for various biochemical reactions. Eukaryotic cells work together to form various tissues and organs in humans enabling their complex systems to function effectively. While prokaryotes form simple single celled organisms like amoeba.

Plants are made up of eukaryotic cells which enable it to carry out photosynthesis. The upper epidermis is a single layer of cells containing few or no chloroplasts. These cells are quite transparent, allowing most of the light that strikes them to pass through to the underlying cells. The upper surface is covered with a waxy, waterproof cuticle, which serves to reduce water loss from the leaf. The next layer is made up of palisade cells which consist of one or more layers of cylindrical cells. The cells are packed with chloroplasts and are the site of photosynthesis in the leaf. The spongy mesophyll cells lye under the palisade cells. They are irregular in shape and loosely packed. Their main function is the temporary storage of sugars and amino acids synthesized in the palisade layer. They also aid in the exchange of gases between the leaf and the environment. During the day, these cells give off oxygen and water to the air spaces that surround them. The air spaces are interconnected and eventually open to the surrounding through pores called stomata. Each stoma (pore) is surrounded by guard cells which have elastic inner walls to regulate the opening and closing of the stomatal pores, hence