One or more polypeptides.
Order of amino acids. Function of protein is controlled by folding, which is controlled by...
Pauling and Corey
discovered alpha helix structure of DNA
folding. alpha-helix, and beta-pleated sheets. hydrogen bonds form to give structure and support.
Secondary folding. Folding of alpha helix and beta pleated sheets and random coiling.
prevent incorrect folding, or association of two separate polypeptides.
Two or more polypeptides come together spontaneously because of R-groups.
1869 discovered DNA, collected nuclei and added protease to break down protein, found DNA and RNA, were not what he expected
discovered chromosomes are made of DNA and protein
Sub-units of nucleic acids. Nitrogen base, deoxyribose sugar, phosphate
Single rings (Thymine and Cytosine)
Double ring. Adenine and Guanine.
Discovered that A, G, C, T, ratio wasn't all 25%. A and T were similar and C and G were similar.
Scientist who was looking to find vaccine for pneumonia in 1928.
Rough (R) Type
Nonvirulent (non-encapsulated) form of virus
Smooth (S) Type
Virulent (encapsulated w/ polysaccharide)
One complete turn in helix is how long?
Size of DNA base
-Different base than DNA: Uracil instead of Thymine
-2' carbon has ribose rather than deoxyribose
More solutes outside membrane. Water moves out.
More solutes inside membrane. Water moves in.
Equal concentration of solutes. Net movement of water is 0.
Found structure of membranes
Gorter + Grendel
Showed membranes are bilayer. Took mammalian RBC's. calculated estimate of surface area. langmuir trough > put lipids in water to create monomolecular layer, which was twice as much as estimated total.
Davson + Danielli
showed bilayer coated with protein to improve surface tension
Singer and Nicholson
Created Fluid-mosaic model
50% lipid, 50% protein by weight.
on outside and inside edge of membrane. easily removed from membrane by change in salt conc.
lipid linked protein
on inside and outside of edge of membrane but linked to lipid which means not easily removed with change in salt conc
integral membrane protein (transprotein)
goes through cell membrane, can go multiple times.
10% of membrane.
Function: signal transduction, intercellular contact (adhesion)
Importance of fluidity
Flexibility (endocytosis), cell division, movement (of flagellum), molecules need to interact
high concentration to low concentration.
Diffusion and osmosis
movement across a membrane without energy or protein
Types of facilitated diffusion
channel mediated and carrier mediated
require input of cellular energy to move things from low conc to high conc
will reach some sort of steady state between concentration gradient and charge gradient, but never completely steady
how many Na+ pumped out per ATP used?
biological catalysts, speed up rate of reaction is the function of
amino acid sequence is the structure of
worked with enzyme that breaks sucrose into glucose and fructose and watched it take place at different conc.