Eukaryotes comprise all members of Plant Kingdom, Fungi and Animal Kingdoms, including the unicellular fungus Yeast, and protozoans. Eukaryotic cells, like prorkaryotic cells are surrounded by a plasma membrane. However, unlike prokaryotic cells, most eukaryotic cells contain internal membrane bound organelles.
Each type of organelle plays a unique role in the growth and metabolism of the cell, and each contains a set of enzymes that catalyze requisite chemical reactions.
The largest organelle in a eukaryotic cell is generally the nucleus, which houses most of the cellular DNA. The DNA of eukaryotic cells is distributed among 1 to about 50 long linear structures called chromosomes. The number
and size of the chromosomes are the same in all cells of an organism but vary among different species of organisms. The total DNA ( the genetic information) in the chromosomes of an organism is referred to as its genome. In addition to the nucleus, several other organelles are present in nearly all eukaryotic cells, the mitochondria in which the cell's energy metabolism is carried out, the rough and smooth endoplasmic reticula, a network of membranes in which proteins and lipids are synthesized and peroxysomes, in which fatty acids and amino acids are degraded. Chloroplasts, the site of photosynthesis are found only in plants and some single celled organisms. Both plant cells and some single celled eukaryotes contain one or more vacuoles, large, fluid - filled organelles in which nutrients and waste compounds are stored and some degradative reactions occur. The cytosol of eukaryotic cells contains an array of fibrous proteins collectively called the cytoskeleton. Cytosol is the soluble part of the cytoplasm. It is located between the cell organelles. The plant cell has a rigid cell wall composed of cellulose and other polymers. The cell wall contributes to the strength and rigidity of plant cell.
Some familiar prokaryotes are: Bacteria, filamentous bacteria (Actinomycetes) and Cyanobacteria.
Some familiar eukaryotes are: Fungi, plants and animals.
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