Exam III Flashcards
What type of cellular movement occurs with a concentration gradient?
Passive diffusion
What type of cellular movement occurs against a concentration gradient?
Active transport
What types of proteins are found within the plasma membrane?
Ion channels, transporters, and pumps
What is the main cation found in intracellular fluid?
Potassium (K+)
What is the main cation found in extracellular fluid?
Sodium (Na+)
This process is characterized by random movements powered by a concentration gradient ONLY (high to low) and it occurs until equilibrium is reached
Diffusion
What are some factors that determine the amount of diffusion that is occurring?
A concentration gradient, particle size, and the permeability of the compound in the barrier it is trying to cross
Can lipid-soluble molecules diffuse through a lipid bilayer?
Yes, but it depends on the solubility of the lipid
Can water and other lipid-insoluble compounds diffuse through the lipid bilyaer?
Yes, but they require protein channels/pores to enter
In diffusion there are two different types of channels that allow substances into and out of the cell. What are they?
Voltage-gated channels and ligand-gated channels.
Sodium channels and potassium channels open when the inside of the cell membrane becomes positively charged. What types of gating would this be considered?
Voltage-gating
The binding of a molecule to a channel will result in this type of gating.
Chemical gating
In this type of cellular transport a carrier protein is required. Each carrier protein has a specific affinity for binding a molecule.
Facilitated diffusion
In facilitated diffusion, transport proteins are sometimes called…
Permeases
This term is used when a solute concentration gives half of Vmax.
Km
This is the maximum attainable reaction rate based on the initial enzyme concentration
Vmax
This term refers to the diffusion of water across a semipermeable membrane, but not solutes.
Osmosis
During osmosis, ____allows water into the plasma membrane.
Aquaporins
This is the pressure applied to stop the flow of water to the side of the highest concentration.
Osmotic Pressure
When the osmotic pressure inside and outside of the cell is the same.
Isotonic
This term is used to describe cells that have a higher osmotic pressure inside than outside. Water is moving into the cell, which increases cell volume.
Hypotonic
This term is used to describe cells that have a higher osmotic pressure outside of the cell rather than inside. Water is moving out of the cell, which decreases cell volume.
Hypertonic
What is the term used to describe a scalloping of the cell membrane?
Crenation
Which type of cells are more resilient to changes in osmotic pressure? Animal or Plant?
Plant cells, because they have a cell wall.