AP Bio Chapter 6-7 Part 2 Flashcards
What’s the function of cholesterol
Acts as a “temperature buffer” to help maintain membrane fluidity over a range of temperatures
What’s the structure of cholesterol
A steroid lipid
What does membrane proteins moving around show
They are diffusible
What is the structure of membrane proteins
Various, depending on the role they play
What do integral proteins do
Penetrate one or both layers of the bilayer
What do peripheral proteins do
Associate with the membrane but don’t penetrate the bilayer
What varies according to the role of that protein
The polarity of different regions of a protein
What are the functions of membrane proteins
Transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining, attachment to the cytoskeleton and extra cellular matrix
What happened to the proteins at the end of the 1 hour experiment
The proteins mixed
What is the structure of membrane receptors
Integral proteins that span the bi layer with regions (domains) that extend extra and inter cellularly
Function of membrane receptors
Signal transduction
Signal transduction
The receipt of cellular messages from the environment and the relay (transduction) of those messages into the cell for response
Membrane receptions are exploited by
Viruses
Structure of glycoproteins
Integral proteins that span the bilayer with short polysaccharide residues projecting extra cellularly into the environment.
Function
Cell to cell recognition, serve as an identifying marker in cellular populations (like your body)
Glycoproteins are a complication for
Organ transplants
Structure of cell wall
A cross linked network of structure polysaccharides
Chitin
Fungal cells
Peptidoglycan
Bacterial cells
Cellulose
Plant like cells
Function of cell walls
Structural support only, cell walls are non living
No cell walls in
Animal cells
Structure of extra cellular matrix
A network of connective proteins and “proteoglycan” molecules outside of the cell membrane of animal cells
Function if extra cellular matrix
Cell anchorage, cell communication
Only _______________ have any major ECM
Animal cells
Structure of intercellular junctions
Proteins that connect cells to other cells, depending on junction, a channel between cells may exist
Functions of intercellular junctions
Anchorage and transport(“open” junctions only)
Open junctions are in
Plants
Closed junctions are in
Animals
Plasmodesmata
Open channels on plant cell walls
Gap junctions
Open channels between animal cells
Desosomes
Cellular “rivets” that anchor cells to basement membranes in tissues
Tight junctions
Cell-cell connections that make a waterproof seal
