Chapter 3: The cell-Anatomy and Division questions answered!

Chapter 3: The cell-Anatomy and Division questions answered!What 3 parts do all cells have? Nucleus, plasma membrane, and cytoplasm. Nucleus Control center of the cell and is necessary for cell reproduction. 00:17 01:08 Chromatin Genetic threadliike material that is when the cell is not dividing. Chromosomes A coiled and condesed chromatin that forms a darkly staining rodlike bodies. Nucleoli One or small bodies that assembles sites for ribosome. Nuclear membane A double-layered porous membrane that bounds the nucleus. Plasma membrane A membrane that separates cell contents from the surrounding environment. Has a double-layered lipid structure that protein molecules float in. Micro Villi finger like projections that greatly increase the surface area of the cell. Cytoplasm Cell contents outside of the nucleus and its the major site of most activities carried out by the cell. Cytosol The fluid part of the cytoplasm. Inclusions Other substances that are not part of the active metabolic machinery of the cell. Ribosomes Spherical bodies composed of RNA and protein. Actual sites of protein synthesis; seen floating free or attached to rough ER. 00:02 01:08 Endoplasmic Reticulum Membranous system that extends throughout the cytoplasm; There are 2 varieties, rough and smooth E.R. Rough ER Studded with ribosomes. Provides an area for storage and transport of the proteins made on the ribosomes to other cell areas; external face synthesizes phospholipids and cholesterol. Smooth ER A site of steroid and lipid synthesis, lipid metabolism, and drug detoxification. Golgi Aparatus Stack of flattened sacs with swollen ends and associated small vesicles; found close to nucleus; plays a a role in packaging proteins or other substances for export from the cell or incorporation into the plasma membrane and in packaging lysosomal enzymes. Lysosomes Various-sized membranous sacs containing digestive enzymes; act to digest worn-out cell organelles and foren substances that enter the cell; if ruptured they have the capacity to totally destroy the cell. Peroxisomes Small lysosome-like membranous sacs containing oxidase enzymes that detoxify alcohol, hydrogen peroxide, and other harmful chemicals. Mitochondria Rod-shaped bodies with a double-membrane wall; inner membrane is thrown into folds, or cristae; contain enzymes that oxidize foodstuffs to produce cellular energy (ATTP) Centrioles paired, cylindrical bodies lie at right angles to each other, close to the nucleus; direct the formation of the mitotic spindle during cell division; form the bases of the cilia and flagella. Whats the difference between: Interphase, Mitosis and Cytokenisi? Interphase is when the cell grows and carries out its usual activites. Mitosis is nuclear divison. Cytokinesis is the division of the cytoplasm; which begins when mitosis is nearly finished. Prophase As cell divisions begins, the chromatin threads coil and shorten to form densely staining, short, bar like chromosomes. metaphase In the briefe stage, the chromosome align along the central plane or equator of the spindle. Anaphase During anaphase, the centrosomes split, and the chromatids (now called chromosomes again) separated from one another and then move slowly toward opposite ends of the cell with their "arms" dangling behind them. Telophase The chromosome uncoil and resume the chromatin from, the spindle breaks down and disappears, a nuclear membrane forms around each chromatin mass, and nucleoli appear in the daughter nuclei. Cytokinesis Typically beings during telophase. A cleave furrow begins to from approximately over the equator of the spindle and eventually pinches the original cytoplasmic mass into 2 parts.