chapter 7
This property of phospholipids drives spontaneous bilayer formation in aqueous environments.
amphipathicity
These molecules cross membranes most rapidly due to their solubility in the lipid bilayer.
small hydrophobic molecules. Small nonpolar.
This microscopy technique allows visualization of internal cell structures at nanometer resolution but requires non-living specimens.
TEM. Transmission Electron Microscopy
This organelle modifies, sorts, and ships proteins received from the ER.
Golgi Apparatus
Whats the 2nd law of thermodynamics.
Although energy is conserved, usable energy decreases during reactions.
This type of protein contains hydrophobic regions typically arranged as alpha helices spanning the membrane.
integram transmembrane proteins.
Despite being polar, this molecule crosses membranes rapidly due to both its size and specialized proteins.
water.
Aquaporins.
Unlike eukaryotes, prokaryotes lack this membrane-bound structure that houses DNA.
nucleus
A protein destined for secretion is synthesized here before being transported via vesicles.
Rough Endoplasmic Reticulum
A reaction with ΔG < 0 is classified this way and will proceed without energy input.
exergonic
This membrane component modulates fluidity by preventing tight packing at low temperatures and restricting movement at high temperatures.
Cholesterol
This is the net movement of molecules from high to low concentration due to random motion.
diffusion
name 3 types of RNA.
mRNA / Messenger RNA
tRNA / Transfer RNA
rRNA / Ribosomal RNA
A mutation prevents vesicle formation from the ER; this will most directly disrupt this downstream organelle’s function.
golgi apparatus
If ATP synthesis stops, this category of cellular work fails first in membrane proteins.
transport work by active transport proteins.
At this state, molecules still move across the membrane, but there is no net change in concentration.
Dynamic Equilibrium
Water moves toward this condition during osmosis.
Higher solute concentration.
Proteins synthesized on free ribosomes are most likely destined for this location.
cytosol
This organelle converts chemical energy from food into ATP via cellular respiration.
mitochondrion
Enzymes accelerate reactions by lowering this specific energy barrier.
activation energy Ea
This type of transport moves solutes against their concentration gradient using ATP.
active transport
how many Na+ and K+ does the NA/K pump move?
3 NA+ out, 2 K+ in.
Vesicle movement along “tracks” inside the cell depends on this structure and ATP-powered motor proteins.
cytoskeleton
A toxin disrupts microtubule formation; predict two major cellular processes that would fail
Intracellular transport and cell division due to spindle formation. Loss of tracts in cell structure.
In a metabolic pathway, the final product shuts down the first enzyme; this regulatory mechanism prevents waste and is called this.
feedback inhibition.