chapter 15 Flashcards
Contains main genome; DNA and RNA synthesis.ny
nucleus
Synthesis of most lipids; synthesis of proteins for distribution to many organelles and to the plasma membrane.
ER
Modification, sorting, and packaging of proteins and lipids for either secretion of delivery to another organelle.
golgi
Intracellular degradation
lysosomes
Sorting of endocytosed material
endosomes
ATP synthesis by oxidative phosphorylation
mitochondria
ATP synthesis and carbon fixation by photosynthesis
chloroplasts
Oxidation of toxic molecules
peroxisomes
Contains proteins that act as binding sites for the chromosomes.
inner nuclear membrane
Provides structural support for nuclear envelope
nuclear lamina
Closely resembles the membrane of ER.
outer nuclear membrane
Consists of one or two short sequences containing several positively charged amino acids. (lysines & arginines)
nuclear localization
Special proteins that aid in the transport of the protein across the two membranes and help fold it back into its tertiary structure once inside.
chaperone proteins
Completely translocated across the membrane and enter the ER lumen
water-soluble proteins
Partly translocated across the membrane and become embedded in it.
prospective transmembrane proteins
Present in cytosol, binds to both the ribosome and the ER signal sequence of polypeptide when it emerges from ribosome.
signal-receptor particle (SRP)
Distinctive coat protein on cytosolic surface; help shapes the membrane into a bud.
coated vesicles
Protein that interacts with the t-Snare prior to joining of target and vesicle snares.
snap-25
Process of cells detecting and responding to signals in the extracellular environment.
cell signaling
Extracellular signal molecule binds to receptor
reception
Transfer of signal from outside of cell to inside of cell
signal transduction
Response is initiated and/or occurs entirely within receiving cell.
cellular response
Long distance signaling that is able to signal the whole body, occurs through the systematic circulation.
endocrine signaling
Signaling in the neighborhood or communication to neighboring cells. Act as local mediators to influence neighboring cells. Depends upon diffusion and regulated by factors.
paracrine & autocrine signaling
Contains metabolic pathways; protein synthesis; the cytoskeleton.
cytosol
Certain type of cell will release the signal and a different type of cell will respond to signal.
paracrine signaling
Certain type of cell will release the signal and the same cell will respond to it.
autocrine signaling
Involves neurons delivering messages across long distances. Delivery is quick and specific.
neuronal signaling
Occurs between cells that are in direct contact with each other.
contact-dependent signaling
Protein molecule usually found inside of on the surface of a cell, that receives chemical signals from the outside.
receptor
Change permeability of cell membrane to certain ions. Signaling molecules regulates opening of ion transport channel.
ion-channel-coupled receptors
Activate membrane bound proteins that then trigger intracellular signaling pathway.
G-protein-coupled receptors
Receptor has enzymatic capabilities or receptor activates associates with an enzyme.
enzyme-coupled receptors
Largest family of such enzyme-coupled receptors, that phosphorylate their substrate proteins on tyrosine residues, includes receptors for most polypeptide growth factors.
receptor tyrosine kinases (RTKs)
Any permanent alteration in the nucleotide sequence of DNA.
mutation
A mutation that alters a single base.
point mutation
Large regions of DNA effecting the normal chromosome structure.
chromosomal mutations
Chemical or physical agents that interact with DNA to cause mutations.
mutagens
Mutagens that lead to cancer.
carcinogens
Genes that exhibit a gain-of-function in cancer.
oncogenes
Normal functioning form of oncogene.
proto-oncogenennn
Genes in which a loss-of-function plays a casual role in cancer.
tumor suppressor genes
Functions to regulate the cell cycle by activating the expression of genes involved in G1 checkpoint control upon DNA damage.
p53
