-
interphase
The cells life cycle is a series of changes- from formation until reproduction of itself- interphase is the longer period during which the cell gows and carries out its usual activities and cell division
-
mitosis
division of cell division, mitosis is nuclear division.....the product of mitosis is 2 daughter nuclei that are genetically identical to the mother nucleus
-
cytokinesis
division of the cytoplasm which begins after mitosis is nearly complete. If cytokinesis does not occur binucleate or multinucleate cells form, common in the liver
-
cell
structural and functional unit of all living things, complex entity
-
3 major regions of the cell
nuleus, plasma membrane, cytoplasm
-
chromatin
threadlike genetic material loosely dispersed throughout the nucleus
-
chromosomes
when the cell is in the process of dividing to form daughter cells, the chromatin coils and condenses- forming dense, darkly staining rodlike bodies
-
nucleoli
one or more small round bodies, primarily protiens and ribonucleic acid (RNA)
-
nuclear envelope
double layered pourous membrane, distinguished by large nuclear pores
-
plasma membrane
seperates cell contents from surrounding environment.
-
selective permeability
valuable cell proteins and other substances are kept within the cell and excreta or wastes pass to the exerior
-
microvilli
fingerlike projections, increase the surface area of the cell available for absorption or passage of materials and for binding molecules.
-
cytosol
fluid cytoplasmic material in the cytoplasm where the most cell activities are carried out
-
organelles
metabolic macheinery of the cell, highly organixed to carry out specific functions of the cell...include ribosomes, endoplasmic teticulum, Golgi apparatus, lysosomes, peroxisomes, mitochondria, cytoskeletal elements and centrioles
-
Ribosomes
densly staining, roughly spherical bodies composed of RNA and protein: actual sites of protein synthesis
-
endoplasmic reticulum (ER)
highly folded system of membraneous tublues and cisternae (sacs) that extend through the cytoplasm- provides a system of transport of cellular substances (mainly proteins) from one part of the cell to another
-
rough ER, smooth ER
- rough ER is studded with ribosomes, its cisternae modify and store newly formed proteins and dispatch them to other areas of the cells
- smooth ER- does not participate in protein synthesis, it is present in cells that produce steroid based hormones, and abundant in cells that are active in lipid methobllism and drug detoxification (ex: liver cells)
-
Golgi apparatus
stack of flattened sacs with bulbous ends generally found close to the nucleus; proteins delivered from rough ER are modified, segregated and packaged in membranous vesicles that 1. incorporated in to the plasma membrane 2. become secretory vesicles that release their contents 3 become lysosomes.
-
lysosomes
various sized membrane bound sacs containing powerful digestive enzymes
-
Peroxisomes
like lysosomes, enzyme containing sacs, they detoxify harmful substances, such as free radicals using oxygen, abundant in kidney and liver cells
-
mitochondira
rod shaped bodies with a double membrane wall - catalyze the reactions of Krebs cycle (oxidative respiration)- produce energy captured in the bonds of ATP molecules, ready energy to power the cells- powerhouses of the cell
-
cytoskeletal elements
support and move substances within the cell
-
microtubules
slender tubules formed of proteins (tubulins organize the cytoskeleton and direct formation of the spindle formed by the centrioles during cell division- also transport substances down the elongated cells, suspend organelles and help maintain cell shape
-
intermediate filaments
stable proteinaceous cytoskeletal elements that act as internal guy wires to resist mechanical forces acting on cells
-
microfilaments
ribbon or cordlike elements formed of contractile proteins, primaily actin- important in cell mobility and contrast
-
centrioles
lie close to the nucleus in all animal cells capable of reproducing themselves, rodshaped bodies that lie at right angles to each other- during cell division they direct the formation of the mitotic spindle, also form the cell projections called cilia and flagella.
-
life cycle stages
- interphase
- prophase
- metaphase
- anaphase
- telophase
- cytokinesis
-
prophase
first and longest stage of mitosis, formation of chromosomes
-
metaphase
brief 2nd stage of mitosis in which chromosomes migrate to the central plane of th spindle and align along the plane in a straight line
-
anaphase
3rd stage of mitosis- the enzyme separase cleaves cohesin and centromeres split- moving chromosomes look V-shaped
-
telophase
final phase of mitosis, chromosomal movement stops, prophase in reverse. mitosis ends, briefly has 2 nuclei
|
|