APBIO Topic 3,4,5 Plasma Membrane and cell cize

hydrophilic

In the phospholipid what is the head?

hydrophobic

In the phospholipid what is the fatty acid tails?

unsaturated fat

A lipid made from fatty acids that have at least one double bond causing a kink in the tail

plasma membrane

separates internal cell environment from external environment

Phsopholipids

plasma membrane is primarily comprised of what?

bilayer

What do phopholipids form?

selective permeability

the ability of membranes to regulate the substances that enter and exit

toward aqueous environments

which way is the hydrophilic heads oriented?

away from aqueous environments

which way is the hydrophobic tails oriented?

fluid mosaic model

A model to describe the structure of cell membranes

fluid

membrane is held together by weak hydrophobic interactions and can therefore move and shift

temperature

affects fluidity

unsaturated hydrocarbon

help maintain fluidity at low temps

cholestrol

help maintain fluidity at high and low temps

high temperature

reduces movement

low temperature

tight packing of phospholipids

mosaic

comprised of many macromolecules

integral proteins

Proteins embedded within the lipid bilayer.

amphipathic

integral proteins are_____

peripheral proteins

proteins that are not embedded in the lipid bilayer

loosely bonded to the surface

peripheral proteins are ____

glycolipids and glycoproteins

important for cell to cell recognition

glycolipids

carbohydrates bonded to lipids

glycoproteins

most abundant; carbohydrates bonded to proteins

cell wall

what do plants have that covers their plasma membrane?

extracellular structure

what kind of structure is a cell wall?

shape, structure, protection, regulation of water intake

what does the cell wall provide?

cellulose

what is the cell wall composed of?

plasmodesmata

hole-like structures in the cell wall filled with cytosol that connect adjacent cells in the plant cell wall

cell size

cellular metabolism depends on what?

function

the size of a cell will dictate what?

high

cells want what kind of SA:V

high

small cells have what kind of SA:V ratio?

high SA:V ratio

Optimizes exchange of materials at the plasma membrane

lower SA:V

larger cells have what?

lower SA:V ratio

lose efficiency exchanging materials, demand for resources increases, and rate of heat exchange decreases