Membrane Structure Chap5 Flashcards
Plasma Membrane
Defines a cell , outlines its borders and how it interacts with its surroundings
They carry a marker that allows cell to recognize one another
Two components of plasma membrane
Glycolipid
Glycoproteins
Passive transport
Substance move from an area of higher concentration to an area of lower concentration
Concentration gradient
A physical space in which there is a single substance concentration range
Peripheral protein
Membrane exterior
Aquaporin
Channel protein that allows water to pass through the membrane at a very high rate
Channel Protein
They are trans membrane proteins, have hydrophilic domains
Carrier Protein
They are specific to a substance
Do protein changes shape
Yes
When their hydrogen bond is affected
Osmosis
Is the movement of water through a semi permeable membrane according to the water concentration gradient across the membrane.
Tonicity
It’s how an extra cellular solution can change the cells volume by affecting osmosis
Example of hypotonic
Cytoplasm
Extra cellular solution have a lower solute concentration
Types of proteins
Carrier protein : they have the ability to change their shape , moving the bounded molecules from cells outside to its interior
Channel : they help polar substances get into the membrane eg aquaporin
Integral protein : completely integrated into the membrane
Peripheral proteins: attached to integral protein, may serve as enzymes, structural attachment to cytoskeleton, cell recognition sites
( cell specific proteins)
Size of plasma membrane
5-10nm in thickness
Phospholipids is made up of?
Glycerol, 2 fatty acids and a phosphate linked head
Cell identification
Glycocalyx ( sugar coating)
Important for embryonic development, cell to cell attachment to form tissue.
Osmolarity
Describe the total concentration of solutes
Solution with low solute (hypotonic) have low osmolarity.
Water enters the cells
Solute with high solute (hypertonic) have high osmolarity
Water leaves the cell
What are the 3 types of carrier protein
Uniporter : specific ion or molecules
Symporter : different molecules to same destination
Antiporter : different molecules, different destination
What is one of the important pump in human cell
Sodium potassium pump Na+ K+ ( electrogenic pump)
It moves Na into cell at the same time K out of the cell
Vacuole
Storage of water, waste disposal and nutrients
