Terms in this set (25)
- chromatin is when the DNA not condensed
- chromosomes is condensed chromatin when the cell is ready to divide
-histones serve to organize DNA which coil around it into bundle nucleosomes (8 histones)
- nucleolus inside the nucleus are the maker of ribosomes (rRNA)
- dense fibrillar network inside nucleus of eukaryotic cells
- Provides mechanical support; also helps regulate DNA replication, cell division, chromatin organization.
irregular shaped region within the cell of prokaryote that contains all/most generic material
this is an area, not a structure! metabolic activity and transport occur here. Cyclosis is streaming movement within cell. Doesn't include nucleus, but does included cytosol, organelles, everything suspended w/in cytosol but nucleus
cytosol doesn't include the stuff suspended within the gel-like substance, it is JUST the gel-like stuff. Think jello vs veggie stew.
60S + 40S = 80S, prokaryote (50S + 30S = 70S); the two subunits produced inside the nucloleus moved into the cytoplasm where they assembled into a single 80S ribosomes (larger S value indicates heavier molecule). Made of RNA+protein, function to make proteins.
rough ER (with ribosomes) creates glycoproteins by attaching polysaccharides to polypeptides as they are assembled by ribosomes. In eukaryotes the rough ER is continuous with the outer nuclear membrane.
Smooth ER (no ribosomes) synthesizes lipids and steroid hormones for export. In liver cells, smooth ER has functions in breakdown toxins, drugs, and toxic by-products from cellular rxn. Can also store ions, e.g. Ca 2+
vesicles produced from Golgi that contain digestive enzymes (low pH for function); any enzyme that escape from lysosomes remains inactive in the neutral pH of cytosol (other source says autolysis) (lysosomes in plant cell - maybe, but generally taught as none). Functions in apoptosis (releases contents into cell).
transport of various substances in vesicles (cis face is for incoming vesicles, trans face for secretory vesicles). Has flattened sacs known as cisternae.
break down substances (H2O2 +RH2 => R + 2H2O), fatty acid, and amino acid; common in liver and kidney where they break toxic substances. In plant cell, peroxisomes modify by-products of photorespiration. In germinating seeds, it is called glyoxysomes break down stored fatty acids to help generate energy for growth. Peroxisome produce H2O2 which they then use to oxidize substrates, they can also break down H2O2 if necessary (H2O2 => H2O + O2)
made up of protein tubulin, provide support and motility for cellular activities; spindle apparatus which guide chromosomes during division; in flagella and cilia (9+2 array; 9 pairs + 2 singlets in center) in all animal cells and lower plants (mosses, ferns).
provide support for maintaining cell shape.
made up of actin and involved in cell motility. (skeletal muscle, amoeba pseudopod, cleavage furrow)
microtubules organizing center
include centrioles and basal bodies (are at the base of each flagellum and cilium and organize their development). 9x3 array. Plant cells lack centrioles because its division is by cell plate instead of cleavage furrow - note that plants DO have MTOC's.
move materials between organelles or organelles and the plasma membrane
temporary receptacles of nutrients; merge with lysosomes which break down food.
large, occupy most of plant cell interior, exert turgor when fully filled to maintain rigidity. Also store nutrients, carry out functions performed by lysosomes in animal cells. Have a specialized membrane (tonoplast)
plants store starch, pigments, and toxic substances (nicotine).
in single-celled organisms that collect and pump excess water out of the cells (prevent bursting). Active transport. Found in Protista like amoeba and paramecia, organisms live in hypotonic environment.
found in plants, fungi, protists, and bacteria (cellulose in plants; chitin in fungi; peptidoglycans in bacteria, polysaccharides in archea). Provides support. Sometimes a secondary cell wall develops beneath the primary one.
found in animals, in area between adjacent cells (beyond plasma membrane and glycocalyx); occupied by fibrous structural proteins, adhesion proteins, and polysaccharides secreted by cells; provide mechanical support and helps bind adjacent cells (collagen is most common here, we also see integrin+fibronectin).
found in plant cells. Chloroplasts (site of photosynthesis), leucoplasts (store starch), chromoplasts (store carotenoids)
make ATP, also fatty acid catabolism (B-oxidation)! (fatty acids are made in cytosol). Also have their own circular DNA and ribosomes (gives rise to endosymbiotic theory!). Have a double layered membrane.
microtubules (ex. flagella & cilia), microfilaments, intermediate filaments. In eukaryotic cells, aids in cell division, cell crawling, and the movement of cytoplasm and organelles.