Membranes and membrane transport Flashcards
What is the plasma membrane made out of
phospholipid bilayer - go to the other deck of flashcards if u wanna know more abt that.
what is an integral protein
protein within the phospholipid bilayer
peripheral protein
outtta the bilayer so in the extracellular space.
functions of integral proteins
transport diff molecules across the biylaer cuz the middle is hydrophobic - sooo these proteins r amphipathic meaning both phobic and phillic. which allow diff molecules to be transported.
integral proteins r usually transmembrane - so they extend across the bilayer.
peripheral proteins ka function
hydrophillicccccc so they chill on top of the bilayer cuz the top/head part is Phillic so then they only interact with same same molecules like the Phillic heads of the bilayer. etc
what is selective permeability and what charge does the intra/extra cellular space of a cell have.
SP: Selective permeability refers to the property of biological membranes to allow certain substances to pass through while restricting the passage of others. This selectivity is based on factors such as size, charge, and polarity of the molecules attempting to cross the membrane. Essentially, selective permeability allows the cell to regulate the movement of substances in and out of the cell, maintaining internal balance and functionality.
intracellular space is positively charged
extracellular space is negatively charged.
facilitated diffusion
spreading out of something due to something that doesn’t require energy.
Facilitated diffusion is a type of passive transport across biological membranes that involves the movement of molecules or ions from an area of higher solute concentration to an area of solute lower concentration with the assistance of specific transport proteins.
what r transport proteins, how many r there and r they integral or peripheral
2 types: channel and carrier protiens
these r integral proteins - passive transport mechanisms
what is the term called for facilitated diffusion of water
osmosis baby
what is active transport
moving molecules or ions w the use of energy, so usually against the concentration gradient (CG).
CG is basically ur moving from a place that has a lot of solute to a place that has less solute.
what type of protein is used in active transport
protein pumps brooo
these pump the molecules - now they pump bcz they need energy in the form of ATP to move these molecules, since they r moving AGAINST the concentration gradient - uphill - this is direct active transport cuz ur using energy
what is the main typa protein pump
sodium - potassium pump
Na+ K+ pump.
moves sodium outta the cell n potassium into, occurs continuously.
what r the three types of channel proteins, what do they transport and what type.
- sodium channel (mechanicaly or ligand gated) - literally just means does it open by itself or does it need a signal from our 5 senses to open it. - moves shit into the cell-remains closed until activated.
- voltage gated sodium channel (means it needs a certain volt of elec to open it)-moves into cell- closed until activated.
- voltage gated potassium channel - moves shit outta cell - closed until activated.
ALL R GOING DOWN THEIR CONCEN G
what typa change does the na-k+ pump go thru
conformational change
where does facilitated diffusion, active and passive transport take place?
Yes, both facilitated diffusion, passive and active transport occur in neurons. Neurons utilize various mechanisms to transport ions and molecules across their membranes, including passive diffusion and facilitated diffusion, to maintain proper function and signaling.
what is a axon in the neuron
is the long parts of the neuron, that transmit info from one neuron to another or an effector cell like a muscle or gland cell.
They serve as the primary means of communication within the nervous system, allowing signals to travel rapidly over long distances. Think of axons like the long wires that transmit signals in an electrical circuit.
they RECIVE ELECTRICAL SIGNALS FROM THE IONS N MOLECULES N SHIT
what is a myelin sheet bro
protects them axons to make sure some stupid shit doesn’t touch the axon, its a fatty substance so it acts as an insulator to increase the speed at which electrical impulses (action potentials) propagate along the axon.
what r action potentials
They are the means by which neurons communicate with each other and with other cells in the body, such as muscle cells or gland cells.
basically its energy-its that message itself that is transmitted to go to other cells n do their shit yk. Action potentials are the electrical signals generated by neurons to transmit information from one cell to anothe
what is the process of action potential propagation yo
This process involves a rapid and temporary reversal of the electrical charge across the cell membrane, where the inside of the neuron becomes briefly more positively charged compared to the outside. This reversal of charge occurs due to the opening and closing of ion channels in the neuron’s membrane, allowing specific ions, such as sodium (Na+) and potassium (K+), to flow into or out of the cell.
r protein pumps a type of carrier protein yes or no
YESSSIRRR
its cuz they go thru a conformational change n shit yah
what r aquaporins
they r integral proteins what have 4 identical water channels - basically holes that allow water to pass thru. These intergral proteins r tetrameteric meaning they have 4 monomeric subunits, which r quaternary proteins right, kinda like histone proteins,
what is depolarization?
Depolarization is a change in the electrical charge across the cell membrane of a neuron or other excitable cell, where the inside of the cell becomes less negative compared to the outside. In neurons, depolarization is often associated with the initiation of an action potential. During depolarization, voltage-gated ion channels in the cell membrane open, allowing positively charged ions, such as sodium (Na+) or calcium (Ca2+), to flow into the cell.
basically the inside of the cell becomes more positive cuz positive ions go inside like the sodium in the VOLTAGE GATED SODIUM CHANNEL NOT THE SODIUM POTASSIUM POUMP .
what is repolarization
inside becomes more neg cuz the pos ions leave inside of cell.
its when the cells membrane potential is going back to its resting stage
what’s hyper polarization
where the inside of the cell becomes more negative compared to the outside. It occurs when the membrane potential becomes more negative than the cell’s resting membrane potential.
when the line goes under the resting potential state.
