Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
45 Cards in this Set
- Front
- Back
|
magnification
resolution |
increase in apparent size
differentiation of two closely situated objects |
|
|
hematoxylin
|
a dye that reveals DNA/RNA distribuation based on affinity for neg. charged particles
|
|
|
three main methods to study cells
|
microscopy
autoradiography centrifugation |
|
|
autoradiography
|
isotopic labeling of molecules with radioactive substance to track cell structures/synthesis of proteins and DNA/RNA.
|
|
|
Eukaryotic cell sedimentation pattern -
ribosomes, mitochondria, lysosomes? |
bottom - ribosomes
top - mito and lyso. |
|
|
Prokaryotes - two types:
|
bacteria, cyanobacteria.
UNICELLULAR. |
|
|
nucleoid region
|
the nuclear region in prokaryotes. not membrane-bound. contains the single molecule of circular DNA.
|
|
|
how many membrane-type structures in bacteria? what?
|
2. The cell WAll and MEMBRANE.
|
|
|
CYTOSOL
|
the simfluid medium within the cytoplasm that contains suspended organelles
|
|
|
Types of eukaryotic cells:
|
Animal
plant fungi protist |
|
|
Cells walls are present in:
|
plants and fungi only
|
|
|
Chloroplasts are only in
|
plants
|
|
|
centrioles are only in
|
animals
|
|
|
cytoskeleton is composed of
|
microtubules, microfilaments, intermediate fibers.
|
|
|
transport proteins
|
membrane-spanning molecules that allow certain ions and polar molecules to pass through lipid bilayer.
|
|
|
cell adhesion molecules
|
cell recognition/adhesion.
|
|
|
how cell receptors signal
|
-pinocytosis (carry molecule into cell)
-or signal via second messenger. |
|
|
nuclear pores
|
allow selective 2-way exchange of materials between nucleus/cytoplasm.
|
|
|
histones
|
structural proteins complexed in DNA to form chromosomes.
|
|
|
nucleolus - what happenes here?
|
dense region in nucleus where ribosomal RNA synthesis occurs.
|
|
|
ribosomes - what are they?
|
sites of protein production.
2 subunits - large/small. |
|
|
secretory vesicles
|
secreted by the Golgi apparatus to release contents to cell exterior.
|
|
|
rough ER
|
ribosome-dotted endoplasmic reticulum.
|
|
|
ER's general purpose:
|
transpot of secretion-destined materials frmom the cell/throughout the cell.
|
|
|
purpose of smooth ER
|
lipid synthesis, detoxification of drugs/poisons.
|
|
|
purpose of rough ER
|
protein synthesis
|
|
|
lysosomes
|
organelles that contain hydrolytic enzymes for intracellular digestion.
|
|
|
autolysis
|
cell-suicide, through process of lysosomal rupturing and spilling hydrolytic enzymes to digest cellular contents.
|
|
|
2 most common microbodies
|
peroxisomes - break down macro fats, detoxify harmful compounds.
glyoxysomes - used in germinating seedlings. |
|
|
which mito membrane contains proteins of ETC?
|
INNER mitochondrial membrane.
|
|
|
enzymes DO and DON'T
|
DO lower act. energy
DO increase reaction rate DONT affect overall delta G DONT change/get consumed in rxn. |
|
|
cofactors
|
non-protein molecules that activate enzymes by:
1. Stabilizing active state. 2. Aiding in binding of substrate. |
|
|
apoenzyme
|
an enzyme without its cofactor
|
|
|
holoenzyme
|
an enzyme with its cofactor - active
|
|
|
prostethic groups
|
cofactors tightly/covalently bound to their enzyme
|
|
|
Coenzymes
|
cofactors that are organic.
|
|
|
Vmax
|
Maximum velocity of a reaction catalyzed by an enzyme.
-Occurs when Substrate conc. is high compared to enzyme. |
|
|
Michaelis constant
|
K2+K3/K1
Rate of ES breakdown to E + S or P divided by rate of ES formation. |
|
|
How does [S] affect reaction rates?
|
If lower than Km, big impact on rate.
If higher than Km, not big impact; rate is approaching Vmax. |
|
|
Effect of TEMP on enzyme kinetics
|
For every 10 C increase, rate doubles up to 37 C. Above that, the enzyme denatures.
|
|
|
Effect of pH on enzyme kinetics:
|
Optimal is 7.2
Pepsin likes acid in stomach - 2 Pancreatic enzymes like base in small intestine - 8.5 |
|
|
At 1/2Vmax....
|
Km = [S]
|
|
|
allosteric enzyme
|
multiple active sites
multiple subunits |
|
|
allosteric regulators:
|
inhibitors
activators |
|
|
action of allosteric inhibitor:
action of allosteric activator: |
prevent binding of substrate to enzyme. How: stabilize the inactive form.
allow binding of substrate to enzyme. How: stabilize the active form. |
