280 likes | 381 Views
Overview of BCOR 11. (These are just some of the many themes we have talked about this semester.). Structure and Function. pH Scale. 0. 1. Battery acid. 2. Digestive (stomach) juice, lemon juice. +. –. Increasingly Acidic [H + ] > [OH – ]. Vinegar, beer, wine, cola. 3. H.
E N D
Overview of BCOR 11 (These are just some of the many themes we have talked about this semester.)
pH Scale 0 1 Battery acid 2 Digestive (stomach) juice, lemon juice + – Increasingly Acidic [H+] > [OH–] Vinegar, beer, wine, cola 3 H H 4 Tomato juice H + H 5 Black coffee Rainwater H H H 6 H Urine Neutral [H+] = [OH–] 7 Pure water Human blood Hydroxide ion (OH–) Hydronium ion (H3O+) 8 Seawater 9 10 Increasingly Basic [H+] < [OH–] Milk of magnesia 11 Household ammonia Figure on p. 53 of water dissociating 12 Household bleach 13 Oven cleaner 14 Figure 3.8 Water • Cohesion/surface tension • Temperature moderation • Solvent Ability • Hydrophilicity – dissolves polar things & ions • Hydrophobicity – herds away nonpolar things • Ionization ability (pH)
C C C C C C Various forms of Carbon molecules and functional groups H O H H H H C=O C C C =C C H N H H H H H
Carbohydrates Lipids monomers and polymers
Membrane Functions 1. boundaries 6. Cell-cell adhesion 2. Localize specific functions 5. Cell-cell communication 3. transport 4. Signal detection
Transport – channels and pumps • Links to structural proteins • Receptors - doorbells • Enzymes – localized biochemical rxns • Energy Generation – utilize gradient – + H+ ATP H+ + – H+ Proton pump H+ – + H+ – Diffusion of H+ + H+ Sucrose-H+ cotransporter H+ – + VoltageLigand Mechanosensitive – Sucrose +
Animal Cell endoplasmic reticulum ENDOPLASMIC RETICULUM (ER) nucleus NUCLEUS Rough ER Smooth ER Plasma membrane cytosol Centrosome CYTOSKELETON Microfilaments Intermediate filaments ribosomes Ribosomes Microtubules Golgi apparatus Golgi apparatus Peroxisome lysosome In animal cells but not plant cells: Lysosomes Centrioles Flagella (in some plant sperm) Lysosome Figure 6.9 Mitochondrion mitochondrion
A B D C Transition state HO OH OH EA B A OH HO - D C Free energy Reactants HO + B A ∆G < O C D Products Progress of the reaction Figure 8.14 Enzymes bring substrates together to lower the activation energy of a reaction DG = DH - TDS
H2O CO2 LIGHT NADP+ ADP CALVIN CYCLE LIGHT REACTOR ATP NADPH STROMA (Low H+ concentration) O2 [CH2O] (sugar) Cytochrome complex Photosystem II Photosystem I NADP+ reductase Light 2 H+ 3 NADP+ + 2H+ Fd NADPH + H+ Pq Pc 2 H2O 1⁄2 O2 THYLAKOID SPACE (High H+ concentration) 1 2 H+ +2 H+ To Calvin cycle ATP synthase Thylakoid membrane STROMA (Low H+ concentration) ADP ATP P H+ Figure 10.17 Proton gradients power reactions to create high energy ATP NADPH and ATP can be used to transfer energy
Fatty Acid Oxidation (b-oxidation) Priming Step Saturated hydrocarbon 2e- 2 H+ removed Energy is captured in many small steps in this metabolic pathway Ester (acid) unsaturated hydrocarbon -captures Reducing potential NADH + H+ FADH2 Ketone 2e- 2 H+ removed alcohol
DNA TRANSCRIPTION RNA is transcribed from a DNA template. 2 3 4 5 1 3 Poly-A RNA transcript RNA polymerase 5 Exon RNA PROCESSING In eukaryotes, the RNA transcript (pre- mRNA) is spliced and modified to produce mRNA, which moves from the nucleus to the cytoplasm. RNA transcript (pre-mRNA) Intron Aminoacyl-tRNA synthetase Cap NUCLEUS Amino acid FORMATION OF INITIATION COMPLEX AMINO ACID ACTIVATION tRNA CYTOPLASM After leaving the nucleus, mRNA attaches to the ribosome. Each amino acid attaches to its proper tRNA with the help of a specific enzyme and ATP. Growing polypeptide mRNA Activated amino acid Poly-A Poly-A Ribosomal subunits Cap 5 TRANSLATION C A succession of tRNAs add their amino acids to the polypeptide chain as the mRNA is moved through the ribosome one codon at a time. (When completed, the polypeptide is released from the ribosome.) C A U A E A C Anticodon A A A U G G U G U U U A Codon Ribosome Information stored in DNA is used to build proteins DNA DNA -> mRNA -> Protein mRNA polypeptide
Sugar-phosphate backbone Nitrogenous bases 5 end CH3 O– 5 O H CH2 O P O O 1 4 N O– N H H H H H O 2 3 H Thymine (T) O H H CH2 O O P N O N H O– H N H G C H H N N A T H T A H Adenine (A) 1 nm H H O C G 3.4 nm H N CH2 C G O O P H O A T O– N H N H G C H H O H Cytosine (C) T A O 5 T A H CH2 O N P O A T O O 1 4 O– H N H T A Phosphate H H N 2 H 3 DNA nucleotide N H OH G C N Sugar (deoxyribose) 3 end 0.34 nm H H A T Guanine (G) DNA structure
Second mRNA base U C A G U UAU UUU UCU UGU Tyr Cys Phe UAC UUC UCC UGC C U Ser UCA UUA UAA Stop Stop UGA A Leu UAG UUG UCG Stop UGG Trp G CCU U CUU CAU CGU His CUC CCC CAC CGC C C Arg Pro Leu CUA CCA CAA CGA A Gln CCG CUG CAG CGG G Third mRNA base (3 end) First mRNA base (5 end) U AUU ACU AAU AGU Asn Ser C lle AUC ACC AAC AGC A Thr A AUA ACA AAA AGA Lys Met or start Arg G AUG ACG AAG AGG U GUU GCU GAU GGU Asp C GCC GAC GGC GUC G Val Ala Gly GUA GCA GAA GGA A Glu GUG GCG GAG GGG G Ribosomes translate the RNA message into a polypeptide Amino end Growing polypeptide tRNA 3 mRNA Codons 5
Mitosis produces an exact copy of the parent cell. • Used for growth and asexual reproduction. • Meiosis produces reduced (haploid) gametes, which are genetically unique. • Necessary for sexual reproduction. Meiosis generates variation through: - independent assortment of chromosomes - crossing over
Mitosis vs Meiosis Not paired diploid Homologs pair in meiosis 1 Sister chromatids separate in meiosis 2 haploid
DNA is always synthesized 5’ to 3’ DNA replication machine DNA sequences are determined by “poisoning” a synthesis reaction with dideoxy nuclotides PCR is just repeated cycles of DNA synthesis in a test tube
1º messenger Cells detect signal & respond Effector Enzymes Target Enzymes 2º messengers Signal transduction pathways AMPLIFY the signal
trp operon Promoter RNA polymerase Polypeptides that make up enzymes for tryptophan synthesis The trp operon: regulated synthesis of repressible enzymes Regulatory gene Genes of operon trpR trpD trpC trpB trpE trpA DNA Operator mRNA 3 5 mRNA 5 C E D B A Protein Figure 18.21a Tryptophan absent -> repressor inactive -> operon “on”
Cell type–specific transcription Enhancer Promoter Albumin gene All cells have the same genes, but only certain genes are expressed in each tissue Control elements Crystallin gene Liver cell nucleus Lens cell nucleus Different set of activator proteins in the two cell types Liver cell Lens cell Albumin gene not expressed Albumin gene expressed Fig 19.7 Crystallin gene expressed Crystallin gene not expressed