EUKARYA DOMAIN OF LIFE DERIVATION / ORIGIN OF EUKARYOTE • Eukaryote comes from two Greek words “EU” and “KARYOTE” 1. EU means True. 2. KARYOTE means Nuts. • Eukaryote can be defined as those organisms whose cell have nucleus enclosed within the nuclear envelope. • Eukaryotes are composed of the true nucleus. • Eukaryotic cells are the cells contains a membrane bound nucleus and organelles. Examples of Eukaryotes (Eukaryotic cells). 1. plant cell. 2. Animal cell. 3. Protozoa cell. 4. Fungi cell. shimoombah@gmail.com CHARACTERISTICS OF EUKARYOTIC CELL Eukaryotic cells have the nucleus enclosed within the nuclear membrane. The cell have mitochondria (powerhouse). Flagella and cilia are the locomotory organs in a eukaryotic cell. A cell wall is the outermost layer of the eukaryotic cells in plant cell. The cells in the eukaryotic domain divide by a process called mitosis. The nucleus contains a single ,linear DNA which carries all the genetic information of the cell. The eukaryotic cell is comprises of the following parts. 1. Plasma membrane . 2. Cell wall. 3. Cytoskeleton. 4. Endoplasmic reticulum. Divided into two categories such as rough and smooth endoplasmic reticulum. 5. Nucleus. 6. Golgi Apparatus. 7. Ribosomes. 8. Mitochondria. 9. Lysosomes. shimoombah@gmail.com EUKARYOTIC CELL STRUCTURE The diagram below shows the eukaryotic cell structure. shimoombah@gmail.com FUNCTIONS. Cell Wall. It provides the shape to the cell and helps in cell-to-cell interaction. It is a protective layer that protects the cell from injury or pathogen attacks. It is composed of cellulose ,hemicellulose, pectin, etc. Plasma Membrane. The plasma membrane separates the cell from the outside environment. Its comprises of specific embedded proteins (phospholipids) which help in the exchange of substances in and out of the cell. Cytoskeleton. It is present inside the cytoplasm, which consists of microfilaments, microtubules, and fibres to provide perfect shape to the cell, anchor the organelles, and stimulates the cell movement. Endoplasmic Reticulum. It is a network of small, tubular structures that divides the cell surface into two parts: Luminal and Extra luminal. It is of two types namely rough and smooth endoplasmic reticulum. Rough endoplasmic reticulum contains ribosomes while smooth lack ribosomes and therefore it is smooth. Nucleus. The nucleoplasm enclosed within the nucleus contains DNA and proteins. shimoombah@gmail.com It controls all the activities cell. Ribosomes production also take place inside the nucleus. Golgi Apparatus. It is made up of flat disc-shaped structure called the cisternae. They are important site for the formation of glycoproteins and glycolipids. Ribosomes. Its function is to synthesis proteins, and it is composed of proteins and ribonucleic acids RNA. Lysosomes. They are known as “suicidal bags” because they possess hydrolytic enzymes to digest proteins, lipids, carbohydrates, and nucleic acids. Mitochondria. These are also known as “powerhouse” of the cell, because they produce energy. They help in the regulation of cell metabolism. Thank you…..!!! shimoombah@gmail.com