Campbell Chapter 7 Flashcards
What is an amphipathic molecule
molecule that has both hydrophilic and hydrophobic regions
Most membrane proteins and membrane Lipids are _______
Amphipathic
How are proteins distributed in the membrane
They form groups of protein that act as long lasting patches
What interactions hold a membrane together
Hydrophobic interactions
Are membranes Stagnant or Fluid
Fluid
What 2 proteins are found in the membrane
integral proteins and peripheral proteins.
What are Integral Proteins
proteins that are permanently embedded in the cell membrane.
What are Peripheral Proteins
proteins that are attached to the surface of a cell or mitochondrial membrane, but are not embedded in it
What are glycolipids
Lipids that have Carbohydrates covalently bonded
What is a selective permeability of the membrane
the membrane allows some substances to cross more easily than others.
What are transport proteins
Transport Proteins are proteins that span the cell membrane, letting in hydrophilic substances without touching the hydrophobic interior of the membrane
What are Aquaporins
Transport Protein that let water molecules into a cell
Polar molecules are hydrophobic or hydrophilic
hydrophilic
nonpolar molecules are hydrophobic or hydrophilic
hydrophobic
What is Diffusion
the movement of particles of any substance so that they spread out into the available space
How is diffusion ruled
In the absence of any other forces, a substance will diffuse from where it is more concentrated to where it is less concentrated.
Does diffusion need energy
no
What is the diffusion of a substance across a biological membrane called
Passive transport
What is Osmosis
The diffusion of free water across a selectively permeable membrane, whether artificial or cellular
What is Tonicity
ability of a surrounding solution to cause a cell to gain or lose
water
If a cell without a cell wall, such as an animal cell, is immersed
in an environment that is isotonic(same tonicity) to the cell what happens
there will be no net movement of water across the plasma membrane
What does being hypertonic mean
a solution has a higher concentration of solute and lower concentration of water
What does being hypotonic mean
a solution has a lower concentration of solute and higher concentration of water
What is Osmoregulation
the control of solute concentrations and
water balance