Biology~AS

Attachments:

• AS level biology

1. Biological molecules
   1. Carbohydrates
      1. Sugars, Starch, Glycogen, Cellulose
         1. Starch
            1. α glucose
            2. Plants
            3. Medium-term storage
            4. Tight double helix
            5. Branched areas allow hydrolysis
         2. Cellulose
            1. β glucose
            2. Plants
               1. Cell wall
            3. Straight chains
               1. Hydrogen bonds between chains
         3. Glycogen
            1. α glucose
            2. Animals
            3. energy storage
      2. Monosaccharides
         1. All carbohydrates made from
         2. Monomers
            1. Glucose, galactose and fructose
               1. Glucose
                  1. α glucose
                     1. H then OH
                  2. β glucose
                     1. OH then H
            2. 2 make a disaccharide
      3. Disaccharides
         1. Condensation reaction
            1. Forms glyosidic bond
            2. Loss of water molecule
      4. Polysaccharides
   2. Lipids
      1. contain C, H little O
      2. Dissolve in solvents NOT water
      3. phospholipids
         1. Hydrophobic 'tails'
            1. 2 fatty acid tails
         2. Hydrophillic 'heads'
            1. Glycerol + phosphate group
      4. Saturated-solid no C=C
         1. Max. no. of H atoms
      5. Unsaturated kink C=C
      6. Triglycerides
         1. Condensation reaction
            1. Ester Bond
         2. Carboxyl group
      7. NOT POLYMERS
   3. Proteins
      1. Contains C, O, H, N, S
      2. Amino acid is monomer
         1. Acidic Carboxyl group
         2. Joined by Condensation reaction
            1. Peptide bond
         3. Amino Group
      3. Structure
         1. Primary
            1. Linear sequence of amino acids
            2. Peptide bonds only
         2. secondary
            1. Polypeptide chain coiled or twisted
               1. α helix
               2. β sheet
            2. Hydrogen & peptide bonds
         3. Tertiary
            1. Compact globular chain
            2. Disulphide (covalent) Ionic Hydrogen & peptide bonds
         4. Quaternety
            1. More than one poplypeptide chain
      4. Globular
         1. Metabolic functions
            1. Tertiary structure
               1. Compact shape
                  1. Not stable
      5. Fibrous
         1. Structural functions
            1. Long chains wound into helix
               1. Linked by cross bridges
                  1. very stable
2. Biochemical tests
   1. Test for reducing sugar
      1. Add Benedicts Heat in water bath
      2. +ve result: brick red colour
   2. Test for non reducing sugar
      1. Heat in water bath w/h HCL Neutralise w/h NaOH Add Benedicts Heat in water bath
      2. +ve result: brick red colour
   3. Test for startch
      1. Add Iodine
      2. +ve result: turns blue/black
   4. Test for proteins
      1. Add Biuret Solution
      2. +ve result: turns lilac
   5. Tests for lipids
      1. Add ethanol and shake
      2. +ve result: cloudy white
3. DNA and RNA
   1. DNA
      1. Structure
         1. DNA is a polymer
            1. made up of nucleotides
         2. Nucleotide
            1. Nitrogenous base
               1. Adenine===Thymine Guanine===Cytosine
            2. Phosphate group
            3. Deoxyribose sugar
               1. 5 carbon
               2. One less oxygen than RNA
            4. Phosphodiester bonds
               1. Between Bases phosphate and sugar
         3. Polynucletide chains
            1. Joined by hydrogen bonds
               1. Via condensation reactions
               2. reativley weak
                  1. Double helix makes stronger
      2. Replication
         1. DNA Polymerase
         2. DNA Helicase
         3. Hydrolysis
         4. Condensation reaction
         5. Semi-Conservative Replication
            1. Evidence
               1. Meselson and Stahl
   2. RNA
      1. Differences to DNA
         1. Ribose sugar
         2. Single standed
         3. Adenine===Uracil Guanine===Cytosine
         4. Shorter
4. ATP
   1. Adenosine Triphosphate
      1. Nucleotide derivative
         1. Adenosine
   2. Use
      1. Energy stored in high energy bonds between phosphate groups
         1. Coupled w/h other reactions
            1. Active transport
            2. Minimises energy loss
      2. Phosphorylation
   3. Differences
      1. No. phospahte
         1. ATP
            1. Three
         2. ADP
            1. Two
         3. AMP
            1. One
5. Cells
   1. Eukaryotic cells
      1. Animal and Plant
         1. Nucleus
            1. Nucleolus
               1. RNA and ribosomes made
            2. Nuclear pore
               1. allows movement of mRNA
               2. Holes in the membrane
         2. Cell membrane
            1. Phospholipid bilayed
               1. Polar hydrophillic heads
                  1. Polar means electrons are not equally shared
               2. Non-polar hydrophobic fatty acids
                  1. Non-polar means electrons are equally shared
               3. cholesterol sits between phospholipids
                  1. gives membrane more stability
            2. Glycoprotein
               1. acts as antigen
                  1. Recognise as self
            3. Glycolipid
            4. extrinsic protein
               1. Lying on the surface of bilayer
            5. Intrinsic protein
               1. all the way through the bilayer
            6. Fluid mosaic model
               1. constantly changes shape
         3. Cytoplasm
            1. Semi-liquid
            2. most chemical reactions happen here
            3. contains dissolved ions
         4. Ribosomes
            1. aid manufacture of proteins
         5. Mitochondria
            1. energy release
               1. Aerobic respiration
               2. ATP
         6. Endoplasmic Reticulum
            1. Smooth
               1. no ribosomes
            2. Rough
               1. Ribosomes
         7. Golgi body
            1. Flattened sacks separated by a membrane
         8. vesicle
            1. Transport vessel
            2. Made of phospholipds
         9. Centrioles
            1. microtubles
      2. Plants only
         1. Chloroplast
            1. Contains chlorophyll
            2. Enable photosynthesis
         2. Vacuole
            1. Important for structure
            2. contains mineral ions in water
         3. Cell wall
            1. Structure
6. Microscopy
   1. Resolution
      1. The smallest distance between two particles which allows them to be distinguished as separate artlicles
      2. Half the wavelength of the medium used
   2. Microscopes
      1. TEM
         1. Best resolution
         2. Beam of electrons pass through specimen
            1. Detected on a fluorescent screen
         3. Thin sections of specimen needed
      2. SEM
         1. 3D image
         2. Specimen coated in heavy metals
         3. Thicker structures can be seen
            1. Electrons do not have to pass through sample
         4. Resolution is lower than TEM
   3. Magnification
7. Enzymes
   1. Inhibitors
      1. Competetive
      2. Non-competetive
   2. Stucture
      1. Proteins
         1. Globular
      2. Active site
         1. A specific pattern of amino acids that is complementary to a particular substrate
         2. Model
            1. Lock and key
            2. Induced fit
   3. Biological catalyst
   4. Effects on rate of reaction
      1. Temperature
         1. Increase in temp Increase in RoR Until optimum
            1. Increase in kinetic energy
               1. More successful collisions
                  1. More enzyme-substrate complexes formed
                     1. Increase rate of reaction
         2. Higher than optimum
            1. High temp. causes the bonds in the tertiary structure to break
               1. Denatures active site
                  1. Less enzyme-substrate complexes are formed
                     1. Decrease rate of reaction
      2. pH
         1. Not optimum
            1. Excess H+ and OH- ions
               1. Interfere with charges in bonds of tertiary structure
                  1. Causes them to break
                     1. Less enzyme substrate complexes formed
                        1. Decrease rate of reaction
         2. optimum
            1. No excess H+ and OH- ions
      3. Substrate conc
         1. <----
      4. Enzyme conc
         1. Increase
            1. More enzymes to collide w/h substrate
               1. More enzyme-substrate complexes formed
                  1. Increase rate of reaction
                     1. Up to a point
         2. Decrease
            1. Less enzymes to collide w/h substrate
               1. Less enzyme-substrate complexes formed
                  1. Decrease rate of reaction
8. Diffusion
   1. Osmosis
      1. Water potential
         1. Higher the Ψ purer the water
            1. 0Ψ= pure water
         2. From an are of high Ψ to an area of low Ψ
      2. Solute potential
      3. Partially permeable membrane
      4. Cells
         1. Plant
            1. Turgidity
            2. plasmolysis
         2. Animal
            1. haemolysis
   2. Definition

      Annotations:

      • The natural passive net movement of the particles within a gas or a liquid from a region of high concentration gradient to  an area of lower concentration until a dynamic equilibrium is reached
      1. Passive
         1. Not requiring energy
      2. Net movement
         1. overall movement
      3. dynamic equilibrium
         1. Equal overall but still particles moving
9. Active Transport
   1. Against the conc. gradient
      1. From an area of low to high
   2. Requires energy
      1. In the form of ATP
   3. Uses carrier proteins
      1. At like pumps
   4. Uses
      1. Small Intestine
         1. Uptake of glucose and amino acids
      2. Plant roots
         1. Absorption of mineral ions
      3. Kidneys
         1. Excretion of hydrogen ions and urea
      4. Muscle cells
         1. Exchange of K and Na ions and minerals
10. Cell replication
    1. Meiosis
       1. Genetic variation
          1. Recombination of homologous chromosomes
             1. Crossing over
          2. Independent segregation of homologous chromosomes
             1. Order in which chromosomes line up along side their homologous pair
       2. Mutations

          Attachments:

          • Biology 2
    2. Mitosis
       1. Interphase
          1. S
             1. DNA replicated
          2. G1
             1. period of cell growth
          3. G2
             1. 2nd period of cell growth
       2. Prophase
          1. Chromosomes condense
          2. nuclear envelope disinigrates
       3. Metaphase
          1. chromosomes align at the equator
       4. Anaphase
          1. Chromosomes pulled apart by spindle fibres
       5. Telophase
          1. Nuclei separate
          2. Daughter nuclei are genetically identical
11. Digestion
    1. Enzymes
       1. Carnohydrases
          1. Starch to maltose
             1. Amalyse
                1. Salivary and pancreatic
             2. Maltose to glucose
                1. Maltase
                2. Hydrolysis
             3. Hydrolysis
             4. Breaks glycosidic bond
       2. Lipases
          1. Triglycerides
             1. Lipase
             2. Monoglycerides
             3. Fatty acids
             4. Glycerol
       3. Proteases
          1. Endopeptidases
          2. Exopeptidases
          3. Dipeptidases
    2. Absorption
       1. Carbohydrates
       2. Lipids
       3. Proteins
    3. Adaptations of small intestine
       1. Villi and microvilli
          1. Increase surface are
       2. Muscle tissue
          1. Remain in contact with food
       3. Blood flow
          1. Conc. gradient
       4. single cell
          1. Short diffusion pathway
12. Water
    1. Dipolar
       1. Hydrogen bonds form between oxygen and water
          1. Of different water molecules
    2. High specific heat capacity
       1. Hydrogen bonds
          1. more energy required to break these
             1. Boiling point increases
    3. Large latent heat of evaporation
       1. Lot energy require to evaporate 1 gram of water
          1. Why sweat is an effective way of cooling in animals
    4. Strong cohesion
       1. Tendency of water molecules to stick together
          1. Surface tension
             1. Allows water to be pulled up tubes
                1. xylem in plants
    5. The role of inorganic ions
       1. H+
          1. Determining pH
             1. Function of enzymes
       2. PO3+
          1. ATP
             1. storing energy
          2. DNA
             1. Structural role
       3. Fe 2+/3+
          1. Haemoglobin
             1. Transport of oxygen
       4. Na+
          1. Transport of glucose and amino acids
             1. Na/K pump
13. Selection
    1. Adaptations
       1. Due to mutations
    2. Types
14. Classification
15. Biodiversity