CELL STRUCTURE 1

Question	Answer
What are the major Precursors	H2O CO2 Nitrogen (NH+4,NO-3 and N2)
Name the Organisational levels of Bio molecules	Inorganic Precursors Metabolites Building Blocks Macro molecules Supra molecular complexes
What hold these molecules together	-Covalent Bond -Weaker chemical forces Hydrogen Bond Van Der Waals forces Ionic interaction Hydrophobic interaction
Main factors about Van Der Waals forces	TEMPORARY -Causes electrical interactions -Dipole dipole interaction -Dispersion -Electrons are always moving -Precise fit
Main factors about Hydrogen Bonds	-Hydrogen bonded to an electronegative atom (O/N) -Also connected to a second electronegative atom that serves as a hydrogen bond acceptor -Highly directional -Form straight line -Specific
Main factors about Ionic interactions	-Attractive forces between oppositely charged polar function -Radially disrupted -Can involve ions, permanent dipoles, induced dipoles
Main factor about Hydrophobic interactions	-Caused by non-polar groups excluding water -Often found buried away from aqueous environment - Causes bio molecule interaction -Define the environmental limit that biological systems can function in
What are the two broad classes of cells	Prokaryotes and Eukaryotes
What are three broad domain of life	Eubacteria Archaea Eukaryotes
Name five function of the membrane	1.Exclude certain toxins and ions 2. Responsible for accumulation of cell nutrients 3. Energy transduction 4. Cell locomotion 5.Reproduction
General membranes structure	-Bilayer -Contains lipids and proteins -5nm thick
what is the difference between Eukaryotes and prokaryotes membrane wise	Eukariotic cells have membranes in almost of the organelles and prokaryotes only have plasma membrane
What are biological membranes composed of	Lipids and Proteins
What is the structure of lipids in the membrane	-Amphipathic the membrane has a polar head which is polar and hydrophilic and a non-polar tail which is hydrophobic
What are the two proteins found at the membrane	Integral membrane protein-within Peripheral membrane protein-attached
Explain amphipathic lipids	They form an organised structure in an aqueous environment to minimize water interaction with hydrophobic tail
What is fluid mosaic model	its the ability of the amphipathic membrane to bend, tilt and rotate due to the fluidity of the membrane bilayer. Lipids and proteins can move laterally and rotate
What is the affect of transition temperature	When the temperature is above the transition temp lipids are mobile and flexible, however when the transition temperature is low the lipids are slightly packed. TRANSITION TEMP IS DETERMINED BY THE LIPID COMPOSITION OF THE MEMBRANE
What are two components of amino acids	Carboxylic head group and Hydrocarbon tail
Difference of saturated and unsaturated in tails	Saturated-No double bonds Unsaturated- Has a double bond and puts a bend in the fatty acid
What lipids make up membrane	-Glycerolipids -Cholesterol -Sphingolipids Glycolipids can either be glycerolipids or sphingolipids
What are the features and characteristics of glycerolipids	-Most abundant lipid in the membrane -Glycerophospholipids are responsible for the bilayer. Made up of two fatty acids, a phosphate, and usually one other small molecule
phosphatidic acid	Parent of a variety of phospholipids
what are the polar groups (alcohol and acid ) esterified to	Phosphoric acid which forms the head group
Name the three major phospholipids found in mammalian membrane	-Phosphatidyl-ethanolamine -Phosphatidyl-serine has COO- -Phosphatidyl-choline has CH3-N-CH CH3
What are the features of cholesterol	-Amphipathic lipid polar hydroxyl -Bidirection regulator of membrane fluidity -In high temperature it increases Tm and stabilizes the membrane -Prevents fatty acid tails of phosopholipids from crystallizing -20% of plasma membrane -Second most abundant
Sphingolipids	-Important in cell signaling and signal transduction -More common in brain and nervous system - Sphingomyelin important in membranous myelin sheath found around nerve axon
Lipid rafts characteristic	-Localized regions of elevated glycoshpingolipid and cholestrol content -FA side chains of lipid raft phospholipids more saturated allowing closer packing with sphingolipid acyl chain -Insoluble in non-ionic detergents -Proteins in raft area are associated with cell signalling -Important in signal transduction
Lipid raft characteristics	-Contain twice as much as cholestrol and 30 % more sphingolipids that the rest -Cytocol side of the raft differs in composition from the extracellular side -Different classes of raft contain different configurations of protein
Bacteria cell wall	Gram positive- Purple, thick peptidoglycan and one lipid bilayer Gram negative- Pink, thin peptidoglycan an two lipid bilayer. Direct amide bonds between peptidoglycan
Mitochondria	Powerhouse of the cell two membranes Oxidasive phosphorilation- regenerates majority of ATP in the cell Uses majority of oxygen in the cell
Chloroplast	Converts light and CO2 into sugar Photosynthesis- Light reaction (Energy gathering) Dark reaction ( CO2 fixation)

Next up

Description

Resource summary

Similar

	Created by Ali Mohamed Omar about 5 years ago