Transport Across Cell Membrane Flashcards
That is a phospholipid bilayer that regulates the entry and exit of molecules?
Cell membrane
Transport such as diffusion, require no energy to function.
Passive transport
Transport that requires energy.
Active transport
What is a spontaneous process in which a substance moves from a region of high concentration to a region of low concentration, eventually eliminating the concentration difference between the two regions.
Diffusion
Transport across the plasma membrane occurs unaided in this diffuison, i.e., molecules of gases such as carbon dioxide and oxygen, as well as small molecules like ethanol, enter the cell by crossing the cell membrane without the assistance of any permease. A small molecule in an aqueous solution dissolves into the phospholipid bilayer, crosses it, and then dissolves into the aqueous solution on the opposite side during simple diffusion. The relative rate of molecule diffusion across the phospholipid bilayer is proportional to the concentration gradient across the membrane.
simple diffusion
This is a type of passive transport in which molecules that cross the cell membrane move quickly due to the presence of specific permeases in the membrane. This diffusion occurs only in the direction of a concentration gradient and does not require metabolic energy.
Facilitated diffusion
Water molecules can transport through the cell membrane. The movement of water molecules through the cell membrane is caused by differences in the concentration of the solute on its two sides. This is the process by which water molecules pass through a membrane from a region of higher water concentration to a region of lower water concentration.
Osmosis
The process by which water molecules enter the cell is known as?
endosmosis
the process by which water molecules exit the cell is known as?
exosmosis
Excessive exosmosis causes the cytoplasm and cell membrane in plant cells to shrink away from the cell wall. This is known as ? It is due to this that a plant loses its support and wilts.
plasmolysis
compartment with higher solute concentration is called?
hypertonic
compartment of lower solute concentration, which is described as?
hypotonic
When the internal solute concentration equals the external solute concentration, it is said to be ? Here, no net movement of water in or out of the cells occurs.
isotonic
The amount of water contained within the cell creates a pressure termed?
hydrostatic pressure (osmotic pressure)
What are the two types of passive transport which play a vital role in moving molecules in and out of the cell?
Osmosis and diffusion
What is the process of moving solvent particles across a semipermeable membrane from the solvent’s higher concentration to the solvent’s lower concentration. The complete process does not require energy to take place.
Osmosis
What is the process of moving particles from a region of higher concentration to a region of lower concentration until equilibrium is reached.
Diffusion
What diffusion does not require energy?
Simple diffusion
What diffusion requires ATP?
facilitated diffusion
What is a kind of cellular transport in which substances like amino acids, glucose and ions are transported across cell membranes to a region that already has a high concentration of such substances. As a result, this transport employs chemical energy like ATP to move substances against their concentration gradient. This type of transport is commonly found in the small intestine wall and root hair cells.
Active transport
Active transport is performed by a special type of protein molecules of the cell membrane called the ? They consume energy in the form of ATP molecules.
transport proteins or pumps
What are two sources of energy for primary active transport.
Photon energy and redox energy
What transport allows one solute to move downward (along its electrochemical potential gradient) in order to generate enough entropic energy to drive the transport of the other solute upward (from a low concentration region to a high concentration region).
Secondary active transport
Secondary active transport coupled is also known as?
coupled transport
