Chapter 3 Flashcards
What are the 6 functions of membrane proteins?
Anchoring, Recognition, Enzymes, Receptors, Carriers, Channels
Are cell membranes rigid and uniform?
No
What is a “ raft”
Embedded proteins confined to specific areas on the membrane. They are made up of anchoring proteins and receptors. Other integral proteins drift across the surface of the membrane
What is the glycocalyx
Layer of carbohydrates extending beyond the outer surface of the plasma membrane
What are 4 functions of the glycocalyx?
- Lubrication and Protection
- Anchoring and Locomotion
- Receptors
- Recognition
Describe the permeability of the plasma membrane
Selectively permeable
What is the cytoplasm ?
General term for material between plasma membrane and the membrane of the nucleus
Which contains more proteins - extracellular fluid or the cytoplasm?
Cytoplasm
What percentage of a cell’s weight is protein?
30%
Name the 5 membranous organelles (not including nucleus)
Endoplasmic reticulum, Golgi body, lysosome, peroxisome, mitochondria
Name the 3 components of the cytoskeleton
Microtubules, intermediate filaments, microfilaments
List 5 facts about microfilaments
~Made up of ACTIN
~smallest of the 3 cytoskeletal elements
~anchor to integral proteins of the plasma membrane and to the enclosed cytoplasm. This gives mechanical strength
~microfilaments determine the consistency of the cytoplasm
~ACTIN can interact with MYOSIN to move a portion of the cell or change shape of entire cell
List 5 facts about intermediate filaments
~ strengthen cell and maintain shape
~stabilize positions of organelles
~stabilize position of cell with respect to other cells
~most durable
~insoluble in water
What filament is Keratin
Intermediate - resistance to stretching
List 6 facts about microtubules
~largest filament
~made up of tubulin
~primary component of cytoskeleton-giving strength of cell and anchoring organelles
~form centrioles and cilia
~extend from the centrosome
~ “monorail system” - requires ATP
