Plasma Membrane PAL session questions

amphipathic

describes something with a hydrophobic tail and hydrophilic regions

phosphoglyceride

type of lipid with two fatty chains linked to glycerol via an ester bond

saturation

absense of double bond between C atoms in the hydrocarbon chain of a fatty acid

sphingolipid

type of lipid with a long hydrocarbon tail with a fatty acid chain attached to the amine group

cholesterol

type of lipid made up of inflexible rings

fluidity

describes the property of plasma membrane that allows components to move freely within the membrane

a membrane is a continuous

lipid bilayer

lipid bilayers are populated by

proteins and carbohydrates

proteins and lipids make up the

bulk of the plasma membrane

the head of a phospholipid is

hydrophilic

the tail of a phospholipid is

hydrophobic

what diffusion is the movement of membrane lipid to the other side of the bilayer

transverse

what diffusion is the movement of lipids within the same side of the bilayer 

lateral

integral proteins often take the shape of an

alpha helix

Glycolipids are lipids that have

sugars attached to their heads

what are the 6 functions of the plasma membrane?

compartmentalization: separates inside and outside; encloses intracellular compartments

scaffold for biochemical activities: organizes enzymes for effective interaction

selectively permeable barrier: allows exchange of specific substances

respond to stimuli: receive and produce signals that change cell activity 

interactions with other cells: signaling, exchange, and adhesion 

energy transduction: converting one type of energy into another

what are the three types of membrane lipids

-phosphoglycerides: hydrophobic tails, two fatty acids chains, linked to glycerol with ester bonds, fatty acids are 16 to 22 carbons longs

-sphinolipids: derivatives of amino alcohol sphingoshine, has a long hydrocarbon tail, have a fatty acid chain attached to the amine group, fatty acid chains tend to be more saturated and longer, the hydrophilic head varies

-cholesterol: sterol that makes up 50% of animall membrane lipids, fills space between phospholipid molecules. infleible rings that interfere with movemet of fatty acids tails which stiffen the membrane, membrane with high cholesterol concentrations lose fluidity

list and describe the four groups of membrane proteins

transporters- active or passive transports

anchors- anchor the membrane to macromolecules and adhesion

receptors- receive and transmit signals 

enzymes- catalyze reactions

label the following diagram

True or false: The function of plasma membrane carbohydrates is to recieve and transmit signals. Explain 

false, carbohydrates facilitate cell to cell recognition

what describes the structure of the plasma membrane

a dynamic, fluid mosaic

what type of molecules can diffuse directly through the lipid bilayer of the plasma membrane?

small hydrophobic molecules 

which factor primarily determines the fluidity of the plasma membrane

the concenration of the membrane lipids

what is the primary function of integral membrane proteins

to facilitate the movement of molecules across the membrane

what is the role of carbohydrates attached to proteins and lipids in the plasma membrane

cell to cell recognition 

which function is NOT associated with proteins in the plasma membrane

providing energy for cellular activities