Topic 2 alevel biology

Alternative transcript:

alpha triple hele forms structure of Dones, cartsage is maintained by blood flow/ventilation "water Soluble globular protein "Consists of "bela polypeplide chaina haem group DNA replication DNA helicase binds to DNA "Non-overlapping •Hydrogen bonds between Strands is broken. 1. Free floating nucleotide form hydrogen bond with complementary bases 3. ONA polymerase forms phosphodiester bond between •Degenerale "Each triplet code is separate from the Other triplel in the Chromosome *Universal Some amino acids are enclosed by more than One coden Some four bases •Same Codon encodes same amino acids Topic 2 •Deletion mulation by Meselson-Stahl • New Down made up of one original polynucleotide strand and a new complementary Strand "Amino acids joun legelner to form a posypeplide chain "IRNA is Sungle Stranded molecube woin amino acid bunding sile *[MIA binds to specific amino acids depending on anti-codon (Aclaration) "Complementary anucodon (RA) binds to codon (mm) held together by hydrogen bonds 333 Hydrogen bonding-force of alination besertaon partially charged allows (group) "Ricosome join amino acids allached to 2 URNA molecul (peplide bond) "Adenine paired with inspine/uracil Tonic bonding - Sali bridge beiween appesiely charged groups (8 group) "Doulphide bridges - (ovalent bord belween Suipher wioms and cysteine Protein synthesis •Substitution malation nucleotides •2 new strands of DNA are Synthesised •Semi-conservation replication "Ensures genelic continunity between generations. cells Genetic information passed on •Proven •Translation Mutation • Almost always harmful • Change to DWn sequence •Addition mutation "Where 1 or more bases are added to DNA sequence * ATCGTT-> ATCCGTT "Where 1 or more bases are removed CATCGTT-ATCTT "Guanine paired win Cybosine - Transcription "Hydrogen bond beween complementary bases breath "Where 1 or more bases are changed. · 69 ATCOTT-> ACCGTT Active transport "It uses energy and is in charge of moving. Moucurus DCloss a membrane •Examples •Structure •DNA uncous-strands Separate "One Shand used as a template to make main lani sense surand) "mRNA moves out of nucleus through pove Plaches to ribosome-sue of nexe suage of ps Polypeptides Rapt I "Sagar is absorbed in the blood from the gul in the root hair of planis it allows plants to absorb mineral ions Osmosis "High Sunface area -High water potential gradient Enzymes •Biological catalyse which increase rate of reaction by lowering actuation energy - Active Sile is crea of enzyme where subsicale binds "Enzymes specific to Substrate they bind to. •Factors affecting rate of reaction • Enzyme concentration : Increasing conc- Increase of r Fincrease conc passed certain point- no resetion *Substrate concentration: Increasing conc increase ropr Increase Conc passed certain point no reaction •Temperature: Rate of reaction increase up to optimum lemp "PH ・After optimum temp the rate of reaction decreases "Made up of amino acids polypeptide "Peptide bond ions and •(Ran delachs from amino acids "Process repeated leading to pormation of polypepuide than wetel Step Coden (mun) H₂NC Нака OH • Each one has a tensial alpha carbon odomn *Amino acids (monomer) jaun together to form "Water molecull released •Peptide bond covalent bond -2 amino acids react together - bond formed between Carboxyl group -C. 0 •Diffusion of water across a partially permeable membrone from area of high concentration to area of low concentration •Factors that speed up osmosis: The membran cok g •Plasma membrans •Defines cell borders *Partialle permeable Phospholipids exter Phospholipid Bilayer environment PROOROCPPPPR Genetics (key words) Gene: Aece of an which has a specific sequence of bases Aliele: One of the different forms of a particular gene "Ghenolype: All the acts of an organisons "Phenotype: Bet of chservation Characteristics of an ondwridural (interaction of gerolyge /entvonment) "Retesswe: Allele that produces a feature only if 2 copes are present "Molecure consisting of 2 pally acids •Glycerol and a phosphate - Imed head. "Molecules arranged into bilayer ·Dominant : Alece that produces a feature if only one copy of the week is present • Homno zugple: Induvidual having 2 identical autres of a particular genes • Herozygose : individual having 2 different actres of a particular genes "Manong orld inheritance: Inherisence of one novacteristic S internal environment cholesterol phospholipid Endocytosis and exocytosis *2 ways that substances can be actively transported across membranes usung ATP a group Subsiane • Endocytosis : Cell engulf a substance from its surrounding it's achieved by flued cell membranc folding around substances *Exocytosis: when membrance bound vesicles fuse with plasena membrane before releasing the substance within them cell membrane Gragna Diffusion Passwe movement of particus in fluids Facilitated diffusion • Molecules diffusion through carrier / channel protein "Passwe process -no energy *Net movement of particles down concentration gradient •Factors which affect diffusion "Increase temperature - fasser •Thick membrane- Slower •Channel proteins "Allow pocor compounds aword nan polar central layer of plasma membrane •Carner probeins •When substance bonds to carruer proterm and changes it shape • Change Shape moves Substances from outside the cell to the inside •Cholesterol • lipids that sit with phospholipids in membrane care •Makes membrane more rigid "Membrane bound proseum •Phospholipid bilayer form the fluid (find mosial medel) • "Mosiac"- proteins, carbohydrates and lipid molecules "large molecules embedded in bilayer J look and hey model DNA Structure of a mononucleotide -Bases: 'MANA •Sugar "Purine (2 strogen containing rings): Adenine, quemme Pyramide (1 milgen containing rings) Cylesine Unymine P Deoxyribose Bonding "Prosphodiester band's between phosphate group and corken:5 "Hydrogen bandh belween bases Hydrogen Structure "Hudragen bands hold Structures Bogether gig •Bases •Double-stranded "Alpha devole heer with sugar- phosphate back on each suand "Purine: Adonunt, quam gine Cylesine, uraci *Sugar -Ribose Bonding "Tome aS DAVA Structure -Pauring "A-u Single-Sirandad "Carries codon attach to LRNA Thuring •IRNA •Bases, pairing, sugar, bonding: Same as mibia *Structure "Single-Sleanded "folded into specific palsern "Carrus ansiedons A-T -C-G