Module 3 Flashcards
CAN FREELY move through membrane
-Hydrophobic molecules
-Small neutral molecules
CANNOT FREELY move through membrane
-Proteins & Ions
-Polar organic molecules
4 parts of phospholipid
Head group
Phosphate Group
Glycerol
Fatty Acid Tails
Phospholipid: head group
Chemical properties determine where phospholipid ends up
Phospholipid: phosphate group- Hydrophilic OR Hydrophobic
Hydrophilic, Charged
Phospholipid: Glycerol
3 C chain with 3 OH groups
Acts as BACKBONE
Phospholipid: Fatty Acid Tail
2 long hydrocarbon chains- vary in composition and bond #/rigidity
POLAR phospholipid HEAD groups
PI
PG
CL
CHARGED phospholipid HEAD groups
PS
PE
PC
T or F. Phospholipids form POLYMERS
False
4 lipid types in plasma membrane
Phospholipid
Cholesterol
Glycolipid
Sphingomyelin
Where is Cholesterol found? What group does it have?
Found in ANIMAL tissue
Hydroxyl group <– interact with membrane surface
Rest of cholesterol <– interact with lipid part of membrane
Where are Glycolipids found? What group does it have?
Found in membranes
Has sugar carbohydrate group
Glycolipids purpose
Cell-to-cell signalling
Sphingomyelin structure
similar to phospholipid but has SPHINGOSINE* instead of glycerol
*found around axons of nerve cells
Phosphlipids form 4 types of phospholipid clusters
Micelles
Liposomes
Monolayers
Bilayers
Signalling Molecules
Include proteins involved in cell communication
Integrins
Membrane-bound proteins that facilitate cell adhesion and cytoskeleton movement
Receptors
Faciliate endo/exocytosis on surfacce of cell for signalling
Anchors & Junctions
Help cells move and attach to other cells and the extracellular matrix.
5 types of membrane proteins
- Signal molecules
- Integrins
- Receptors
- Channels & Transporers
- Anchors & Junctions
3 types of transport that regulate phospholipid composition/asymmetry
- Floppies
- Flippase
- Scramblase
Water goes from inside the cell to outside
Hypertonic
Water goes from outside the cell to inside
Hypotonic
Flexibility goes UP when temp goes
UP (because motion goes up)
Flexibility goes up when lipid chains are
SHORTER (more motion)
Flexibility goes up if cholesterol concentration goes
DOWN (becomes less rigid)
Flexibility goes up if protein content is ____ rich
LESS (more movement)
Floppases
FLOP OUT
keep PC, cholesterol and sphingomyelin in exoplasmic leaf
Flippase
FLIP IN
Keep PS, PE, PI abd cytosolic leaflet
Scramblases
SCRAMBLES ASYMMETRY
Briefly disrupts membrane asymmetry by RANDOMIZING phospholipids
Def: Channel protein that has a hydroPHILIC interior to allow water to move through plasma membrane
AQUAPORINS
3 types of passive transport
Simple diffusion
Facilitated Diffusion
Osmosis
2 types of facilaited diffusion
Channel (charged)
Carrier (non-charged binds and changes shape)
What is active transport
molecules move AGAINST CONC gradient
Direct Active Transport
Na+/K+ Antiporter pump uses ATP DIRECTLY to make gradient
Indirect Active Transport
Na+/glucose sympoter
Na+ used to create glucose gradient INSTEAD OF ATP
Active transport: symporters
molecules move in SAME direction
Active Transport: Antiporter
molecules move in OPPOSITE direction
Cellular Metabolism
Sum of all diff reactions taking place in cell
CATAbolism
BREAKDOWN of macromolecules
RELEASE atp energy
Hydrolysis
React with water to remove compound
ANAbolism
PRODUCTIon of macromolecules
CONSUME atp from catabolism
How is ENERGY stored
other than ATP
carbohydrates
fats
protein
What are carbohydrates mainly STORED as
glycogen in muscle/liver
What are fats mainly STORED as
Triacylglcerols –> broken down to release FA’s –> for energy production
What are proteins mainly STORED as
Skeletal muscle –> used when fasting (break down muscle)
What is catabolism? examples?
RELEASE energy (breakdown)
Ex. ATP, A.A
What is Anabolism
Requires energy (production)
Ex. proteins, complex sugars
Where can GTP be found
Translation (elongation step)
What is ATP made up of
Adenine molecule, ribose sugar, 3 phosphates
What is NAD+
Converted to higher energy form by adding H+ and 2e- –> NADH
What is FAD
Converted to higher energy form by adding 2H+ and 2e–> FADH2
What energy process happens in the cristae (inner mitochondrial membrane)
Enzymes convert high-energy compounds into ATP
4 stages of aerobic respiration in the MITROCONDRIA
- pyruvate oxidation
2.krebs cycle
3.electron transport and proton pumping - chemiosmotic gradient
5.ATP synthesis
Other than glucose what can metabolize to produce ATP
Fats & proteins
Where does Fat metabolism occur
mitochondria
What energy source does the BRAIN use
Glucose, Ketones
What energy source does the HEART use
FA’s, Ketones *must be aerobic
What energy source does the SKELETAL MUSCLE use
Glucose, FA’s, Ketones
Protein metabolism
Deamination: Nitrogen (amino group) of A.A is removed (not required for ATP generation)
Muscle Cell Energy NEEDS
LOW: FATS
MEDIUM: CARBS/GLYCOGEN
HIGH:
-MUSCLE GLYCOGEN (anaerobic-> lactate)
-CREATINE PHOSPHATE
-Proteins (last resort)
What enzyme is used when there is excess ATP
Creatine Kinase
OG fluid mosaic model
Assumed to be homogenous and of even thickness
Revised fluid mosaic model
Membrane constituents (phospholipids, cholesterol, proteins)
Hydrophilic groups interact with hydrophobic portions of membrane proteins (membrane proteins, phospholipids, membrane constituents make up lipid raft)
What generates more ATP: NADH OR FADH2
NADH because it enters the ETC first
