Unit 4 quiz Flashcards
What causes gene expression?
High levels of signaling molecules (many bacteria)
Autocrine signaling
a cells signal acts on itself
Local Signaling
paracrine signaling to a cell close or neurotransmitters from one nerve cell to the next
endocrine signaling
long distance: signal (hormone) enters blood system to carry signal far away
Stages of cell signaling
- Reception
- Transduction
- Response
signal molecule
ligand
Plasma membrane receptor
Proteins: water-soluble ligands
G-protein
acts as an on/off switch
Receptor tyrosine kinases
membrane receptors that attach phosphates to tyrosines
receptor tyrosine kinase can…
trigger multiple signal transduction pathways at once
Transduction
relay signals from receptors to target molecules
Protein Kinase
enzyme that phosphorylation and activated proteins at next level
Phosphorylation cascade
amplifies signal
Second Messengers
small NONPROTEIN molecules/ions that can relay signal in cell
Responses
regulates protein synthesis by turning on or off genes in nucleus and regulating activity of protein in cytoplasm
Chromosomes
condensed DNA
Chromatin
DNA and proteins
Somatic Cells
body cells
Gametes
Reproductive Cells
M Phase
mitosis and cytokinesis
Interphase
G1
S
G2
G1
cell grows
S
DNA replicated
G2
grow and prepare
Mitotic Chromosome
duplicated chromosome (sister chromatids)
Cytokinesis
division of cytoplasm
animal cytokinesis
actin microfilaments contract around equator- cleavage furrow forms
Plant Cytokinesis
vesicles sent from golgi line up at equator and form 2 cell membranes
Binary Fision
used by prokaryotes (bacteria and archaea) where two daughter chromosomes actively move apart
