Membrane Structure
what are membrane domains?
functionally specialized areas on the surface where the proteins will organize themselves into
what's the difference between passive and active transport?
passive transport: moves along the gradient
active transport: moves against the gradient, requires energy
name three superfoods that helps with brain function
blueberries, spinach, salmon, turmeric, omega 3, coffee, red grapes, tea, coffee, eggs, strawberries, nuts, avocados, etc...
explain compartmentalization
organelles have enclosed membranes so that chemical reactions are separated within the cell
what are two main functions of the cytoskeleton?
gives cell its shape
allows cell to move
allows organization of internal organelles
what are the four types of membrane proteins?
transmembrane
monolayer-associated
lipid-linked
protein-attached
what is the most regulated ion in the cell?
Ca2+
when are we at our peak cognitive function?
through what process did intracellular membranes evolve?
invagination of the plasma membrane
what is the toughest and most durable cytoskeletal filament?
intermediate filaments
what are the four ways a phospholipid can move within the membrane?
lateral diffusion
rotation
flexion
flip-flop
what can go through a membrane?
small molecules
nonpolar molecules
some uncharged polar molecules
what is the resting membrane potential of neurons?
-60 mV
why do proteins need signaling sequences?
without amino acid signaling sequences, proteins won't know where to go after they're synthesized
what causes progeria and what is the most well-known symptom of the condition?
caused by: defects in nuclear lamina
most prominent symptom: accelerated aging
name one of the three things that could affect how tightly packed a phospholipid can be within the phospholipid bilayer
length
number of double bonds
presence of cholesterol
for Na+/K+ pump, do the Na+ ions move to the inside or outside? what about the K+ ions?
3 Na+ goes outside the cell
2 K+ goes inside the cell
explain depolarization (what ions are associated and where are they going; is the membrane potential becoming more positive or negative)
depolarization: when a neuron receives a signal, it can become more positive inside due to an influx of Na+ ions
what is phagocytosis and pinocytosis?
phagocytosis: ingestion of large particles via large vesicles
pinocytosis: ingestion of fluid and small particles via small vesicles
what two filaments are associated with muscle contraction?
muscle contraction involves the interaction of actin (thin filaments) and myosin (thick filaments)
most common phospholipid?
phosphatidylcholine
for the glucose/Na+ symport, describe whether each component goes along or against the concentration gradient
glucose goes against gradient into the cell
Na+ goes along gradient into the cell
explain excitatory synapse vs. inhibitory synapse (what ions are associated and how does it affect the likelihood of firing an action potential)
excitatory synapse: influx of Na+ depolarizes membrane, increasing the likelihood of firing an action potential
inhibitory synapse: influx of Cl- keeps membrane polarized, decreasing the likelihood of firing an action potential
what are snares used for?
snares are used for docking the vesicle into the membrane properly
what are kinesins and dyenines and which way do they go?
kinesins and dyneins are motor proteins that transport cargo along microtubules
kinesins: move towards the plus end of microtubules (away from the cell center)
dyneins: move towards the minus end (towards the cell center)