brian kinkle biology 1 exam 2

-hydrophillic heads (outside)
-hydrophobic tails (inside)
-integral proteins tether them together
-inside actin and intermediate filaments
-fluid is between proteins

describe the fluid mosaic model

the structure of the plasma membrane

what does the fluid mosaic model describe

fluid- how some parts of the membrane can move around freely
mosaic- components that include phopholipids, cholesterol, proteins, and carbs

what is the fluid part of the fluid mosaic model? Mosaic part?

-when temp increases or decreases
- adding or subtracting double bonds
-adding or subtracting cholesterol
-lengthening the tail

how does the membrane become more or less fluid

peripheral and integral

proteins found in the cell membrane

transmembrane integral proteins

these proteins cross the entire membrane
(some only penetrate the membrane partially)

peripheral proteins

these proteins don't penetrate the bilayer at all

carbs

these are attached to the outer surface of some proteins and lipids

adhere one cell to another

some proteins also

fluidity of fatty acids in the membrane

cholestrol molecules influence the

:)

draw plasma membrane

transporter proteins

selective; only allow certain solutes to enter/ leave the cell through channels or carriers

enzyme proteins

carry out chemical reactions on the interior surface of membrane using themselves to attach to membrane

receptor proteins

membranes are sensitive to chemical messages detected by

identity markers

identify cells for other cells (combinations of proteins are the cells ID tag)

cell to cell adhesion proteins

cells use specific proteins to give themselves together. some are temporary, some are permenant

attachments to cytoskeleton

surface proteins that interact with other cells; anchored to cytoskeleton

proteins that affect membrane structure

wedge shaped proteins can cause membranes to bend, allowing formation of tubes/folded sheets

selective permeability

only allows some molecules through membrane

diffusion

movement of any substance to regions of lower concentration; doesn't require energy

osmosis

water movement (high to low concentration); regulates water balance

active transport

uses energy (ATP) to move materials against a concentration, requires energy, and moves particles up concentration gradient

carrier proteins

transport molecules by changing shape

channel proteins

transport small molecules or ions down a concentration gradient
hydrophillic pathways

hypertonic

water moves out of cell, causing shriveling

hypotonic

water moves into cell, causing cell to burst

isotonic

solution is equal to the amount of water in the cell and out of the cell

!

draw active transport

coupled transport

uses energy stored from a gradient to transport Na into cell down it's concentration gradient at same time it transports a glucose molecule into the cell

!!

draw coupled transport

sodium potassium pump

protein carrier that transports Na and K across plasma membrane
energy provided by ATP hydrolsis
every 3 na out = 2 k in

!!!

draw sodium potassium pump

a chemical or electrical gate

what can open a gated channel

the concentration gradient

where is the energy coming from to drive both simple and facilitated diffusion

symport

transport of things together in the same direction

antiport

opposite direction

uniport

one thing in one direction

antiport

sodium potassium pump is an example of

endocytosis and exocytosis

different mechanisms that cells use to transport large substances across the membrane

endocytosis

cell takes in molecules and particulate matter by forming new vesciles from plasma membrane
envelops food particles with fluid

phagocytosis

paarticules engulfed

pinocytosis

liquids engulfed

receptor mediated endocytosis

bind to receptors/ specific types

exocytosis

cell secretes certain molecules by the fusion of vesicles with plasma membrane

energy

the capacity to cause change

potential energy

stored energy

kinetic energy

energy of motion

a reaction where one atom loses an electron and another atom gains that electron

what happens during a redox reaction

oxidation

the loss of an electron

reduction

the gain of electrons

potential

nuclear

potential

gravitational

potential (mass at rest) and kinetic (mass in motion)

mechanical

potential (charged battery) and kinetic (discharging battery)

electric

kinetic

thermal (heat)

kinetic

radiation

potential

chemical

energy cant be created or destroyed only changed from one form to another

first law of thermodynamic

energy of the universe is increasing
to maintain order life requires constant input of energy

second law of thermodynamic

free energy

energy available to do work
can perform work when temp and pressure are uniform throughout the system

enthalpy

amount of energy stored in a bond
energy contained in the chemical bonds of the molecule symbolized as H
in a cellular reaction the free energy is equal to the _____ of the reactant molecules in the reaction

entropy

measure of disorder

equilibrium

free energy decreases
E reactants= E products

endergonic

more free energy than reactants
entropy increases
takes more energy to clean up room
taking in energy

exergonic

reaction that produces less free energy than reactants
entropy decreases
putting out energy

3 phosphate groups, ribose, and adenine

draw picture of ATP structure

stores energy

ATP

to lower the activation energy to initiate a reaction
modify, increase rate of reaction

what does it mean to catalyze a reaction

enzyme

a protein that acts as a catalyst
made up of amino acids, held together by a peptide bond

proteins, cofactors (metal ions), coenzymes, and prosthetic
proteins with an activation site
substrates that bind to these and form enzyme substrate complex

what are enzymes made up of

cofactor

additional chemical component that aids enzyme activity
nonprotein, typically a metal ion

coenzyme

a cofactor that is a non portein organic molecule

multi enzyme complex

contains several copies of several enzymes packed into an assembly to carry out biochemical reactions

at their active site (it has a unique shape that fits that of the substrate)

how do enzymes bind to their substrate

temp increases enzyme activity until the optimum temp is met

how does temp affect enzyme activity

enzymes are too weak to maintain shape

above optimum temp

hydrogen bonds and hydrophobic interactions that determine the enzymes shape aren't flexible enough to permit an induced for that is optimum for catalysis

below optimum temp

changes shape of enzyme by interacting with noncovalent bonds
changes shape or charge properties of the substrate so that either substrate cant undergo catalysis
as ph increases enzyme activity increases until it reaches an optimal point in which enzymes denatures and as ph increases enzyme activity decreases

how does ph affect enzyme activity

higher substrate concentration = higher rate of a reaction because more substrate molecules will be colliding with enzyme molecules creating more product

how does substrate concentration affect enzyme activity

inhibitor

substance that binds to an enzyme that lowers activity

competitive inhibitor

compete with the substrate for the active site
occupying active site makes substrate unable to bind

noncompetitive inhibitor

bind to another part of the enzyme that changes the shape so the substrate will no longer be able to bind to it

allosteric inhibitor

a substance that binds to an allosteric site and reduces enzyme activity

allosteric site

where non competitive inhibitors bind to on the enzyme that can switch it on and off

allosteric activator

a substance taht binds to an allosteric site and increases enzyme activity

metabolism

sum of all chemical processes occuring within a living cell or organism

anabolism

biosynthetic or constructive part of metabolism
expand energy to build up molecules

catabolism

result in breakdown of complex molecules into simpler compounds
breaking down molecules

allosteric reaction

regulation of an enzyme or protein by binding an effective molecule at the proteins allosteric site

draw allosteric enzyme

draw feedback inhibition

feedback inhibition

control mechanism where an increase in the concentration of some molecules inhibits the synthesis of the molecule

to take energy from food and turn into ATP
flow of energy (bc electrons carry energy with them)

why do cells use redox reactions

NADH

acts as electron receptor
oxidizes energy rich molecules by gaining their electrons
donates electrons to other molecules

substrate level phosphorylation

matabolic reaction that results in formation of adhesion triphosphate or GTP by the direct transfer of a phosphoryl group to ADP or GDP from a phosorylated reaction intermediate
ATP is formed directly by adding a phosphate group to ADP from PEP part of glycolysis
FORMATION OF ATP FROM ADP

glycolysis

breakdown of glucose into pyruvate

to reduce and oxidize other substances and carry electrons

purpose of NAD/NADH

2 ATP
2 NAD+
glucose

inputs of glycolysis

4 ATP
2 NADH
2 pyruvate

outputs of glycolysis

draw glycolysis