BIOL 1P91 AI Quiz Exam Review PDF

BIOL 1P91 -- AI Quiz Exam Review \| Photosynthesis \| Summary \| - Photosynthesis: the process where cells get energy from the sun and turn solar energy to chemical energy (CO2 + H2O Sugar + O2) - Autotrophs: produce their own energy - Phototrophs: produce energy from the sun - Chem...

BIOL 1P91 -- AI Quiz Exam Review \| Photosynthesis \| Summary \| - Photosynthesis: the process where cells get energy from the sun and turn solar energy to chemical energy (CO2 + H2O Sugar + O2) - Autotrophs: produce their own energy - Phototrophs: produce energy from the sun - Chemotrophs: produce energy from chemicals - Consumers/Heterotrophs: consume others to get energy - Photosynthesis contains light and dark reactions - Light reactions, Light + CO2 NADPH + ATP - Dark reactions, NADPH + ATP Carbohydrates +O2 - During photosynthesis energy from the sun is sent to a pigment molecule - Organisms absorb all colour that are not reflected, i.e. in leaves green is reflected - Chloroplasts are where energy is made, made of thylakoids, stack of thylakoids equals a granum - Chlorophylls a and b contain a porphyrin ring. Bound to magnesium - Chlorophylls cause green pigment, carotenoids cause orange pigment - Chlorophyll absorbs then captures light energy - Absorption Spectrum, absorption vs wavelength - Action Spectrum, photosynthesis vs wavelength - Light Reactions - Occur in thylakoid membrane - Rely on light - Z Scheme: 1. Photosystem II, light excites P680, oxidizes water, first step in ATP 2. Photosystem I, energy goes to P700, NADPH is made - Dark Reactions - Occur in the stroma - For every 6 CO2 made, 18 ATP and 12 NADPH are used - Product is G3P - Calvin Cycle: 1. Phase 1: carbon is incorporated to RuBP and rubisco 2. Phase 2: Reduction and carb production, NADPH and ATP are used to do so 3. Phase 3: 10 G3P are converted into 6 RuBP using ATP, starts with inorganic becomes organic - Photorespiration occurs when rubisco adds O2 to RuBP instead of CO2, occurs in hot dry areas where there is less air - Environmental conditions effect photosynthesis - Stomata are small pores on a plant that allow for gas exchange - C3 plants, 3-carbon, lowered efficiency from photorespiration, wheat - C4 plants, 4-carbon, higher efficiency from photorespiration, corn, to survive a hot climate - Captures CO2 and provides a steady supply limiting the chance of rubisco binding to O2 - CAM plants, open their stomata at night, cacti \| Mendelian Patterns of Inheritance \| Summary \| - Inheritance: the passing on of traits from parent to offspring - Pre-Mendelian Theories, - Theory of acquired characteristics: animals adapted to do better - Giraffe grew their neck longer - Blended inheritance: old theory that traits were blended in offspring - If a yellow plant and blue plant bred the offspring would be green - Gregor Mendel, work was ignored than became popular postmortem - Dominant alleles create a functional protein - Single factor crosses, one trait cross - P F1 (all dominant) F2 (ratio was in dominant: recessive 3:1) - Genotype: genetic characteristics, Phenotype: shown characteristics - Mendel used pea plants / pisum sativum because they grew fast and had a variety of traits - Mendel's Three Laws - Mendel's law of segregation, alleles separate in gamete formation - Mendel's law of independent assortment, traits are passed on independently to one another - Mendel's law of separation, alleles are not linked - Types of gene analysis - Test cross, homozygous recessive x dominant, two-factor crosses, punnet square - Pedigree analysis: examines presences of traits among families, used to understand inheritance of generic diseases - Cystic fibrosis, only those who are homozygous display this - Human chromosomes, XY, men = SRY gene, X linked genes, autosomes and sex chromosomes - X-linked traits occur more frequently in men, can't be passed to girl if dad doesn't have it - Morgan's Drosophila experiments confirm this - Wild type alleles: most common gene in a populations - Mutant alleles: uncommon gene - Rare types of gene expression - Incomplete dominance: heterozygote exhibit a trait that is an intermediate between the two - Codominance: both traits are expressed (seen in AB blood type) - Environmental role, phenotypes can be shaped by the environment, i.e. trees will grow longer depending on weather and nutrients - Norm of reaction: the phenotypical range that the environment can influence \| Epigenetics, Linkage, and Extracellular Inheritance \| Summary \| - Gene expression: DNA RNA Protein - DNA mutations affect a phenotype by altering the amount of mRNA - Gene regulation: transient increases or decrease in expression due to the environment - Epigenetic gene regulation: gene expression that are reversible and passed from cell to cell - Vernalization, process in which plants grow in cold temperature to flower - Cold temperatures silence FLC, changes maintained till flowered, then FLC expression increases - Epigenetic Inheritance: epigenetic genes can be passed to offspring from sperm or egg cell - Though most can't, i.e. cigarette exposure won't be passed to an offspring - X inactivation, in female mammals one X chromosome is inactivated at random in all somatic cells, (dosage compensation) - Condensed X is visible in a Barr body only seen in female cats, not male - Calico cats are heterozygous, producing patches where orange is activated and black isn't - Extranuclear Nuclear / Cytoplasmic Inheritance: transmission of genes outside the cell, organelle genomes are inherited maternally - Egg cell provides cytoplasm while male gametes provide nuclear genome - Example leaf colour, transmission of leaf pigmentation does not obey independent assortment, colour solely depended on pigmentation of maternal parent - Mitochondria is inherited from mom so dad can not pass it on, also not T or t - Individuals with a mixture will only exhibit disease if \>60% - When genes are close on the chromosome they are often transmitted together - Linked genes most abundant phenotypes in the F2 generation will be same as P generation - Parental/Nonrecombinant: offspring has same traits as parents (no crossing over in F1) - Nonparental/Recombinant: offspring have a different combination (crossing over in F1) - Genetic linkage mapping: Recombination frequency - = recombinant offspring / total offspring \* 100 - When genes are linked most abundant genes in F2 generation are in P generation \| The Eukaryotic Cell Cycle, Mitosis and Meiosis \| Summary \| - Cell division, used to pass on DNA, though if unregulated it can be very dangerous, occurs in: - Eukaryotes: an organism with a nucleus and organelles - Prokaryotes: an organism with all genetic material in the cell body - Cytogenetics: study of microscopic examination of chromosomes - Karyotype: a photographic representation of chromosomes - Diploid cells have two chromosome sets, haploid have one set - Members of a chromosome pair are called homologs, identical in size and comp but differ - The cell cycle steps (G1 + S + G2 are interphase) (11hr 8hr 4hr 1 hr) - G1, cell grows and commits to division, molecular changes promote progression - G1 checkpoint, proteins determine if needed conditions are met - S, chromosome is replicated, sister chromatid is formed - G2 synthesizes needed proteins - Ensure that all DNA has been replicated - M, divides one cell nucleus into two \| Cytokinesis: divides cytoplasm into two daughter cells - Metaphase checkpoint, monitors the integrity of the spindle apparatus - Miotic cell division (PPMAT) (followed by cytokinesis) (used for replacement of worn-out) - Mitosis happens because cell becomes to o large (DAABS) - Prophase, chromatids condense, nuclear membrane begins to dissociate - Prometaphase, spindle apparatus is formed, centromeres move to two poles - Metaphase, pairs of sister chromatids are aligned in the center - Anaphase, chromatids are broken - Telophase, chromosomes reach their respective poles, nuclear membranes re-form - Result is two genetically identical daughter cells - Dissociate, apparatus (formed), align, break (chromatids), separate (end) - Bivalent: homologous pair of chromosomes associated \| chiasma, connection between crossed chromosomes - Meiosis 1 (creates sex cells, sperm and eggs) (BAMSS) - Prophase 1 chromosomes condense, bivalents formed - Prometaphase 1, nuclear membrane is broken apart, spindle apparatus formed, only one pole - Metaphase 1, bivalents are organized along metaphase plate as a double row - Anaphase 1, segregation of homologs occurs - Telophase 1, nuclei are separated then formed - Bivalents (formed), apparatus (formed), metaphase (plate), segregation, separation - Meiosis 2, separates sister chromatids, DNA is not replicated between, steps are same as mitosis - Produces four haploid daughter cells from one diploid cell - Locus: where a gene is found - Sex production, two haploid gametes unite, create a diploid zygote, requires body pars - Life cycles - Diploid-dominant, most animals, produces haploid gametes in the reproductive organs - Haploid-dominant, fungi organism is haploid, unite to form gamete - Alteration, plants and some algae, diploid stage (sporophyte) haploid stage (gametophyte) - Cyclin-dependent kinases (CDKs), proteins that need a cyclin, they drive the M-phase and guide the G1 phase - Chromosomes are bound at the centromere \| Nucleic Acid, DNA Replication and Chromosomal Structure \| Summary \| - Genes are the blueprints of a human - In 1800s people thought the idea of DNA existed, 1920s people thought protein carried the genes - Frederick Griffith was the first experiment that bacteria can transfer genetic information through transformation - Smooth Bacteria secrete capsule that contains disease \| Rough Bacteria, don't secrete - Griffith found that Rough Bacteria can still cause disease when under heat, Transformation - DNA from the environment is incorporated into the cell - Hershy-Chase found that DNA was the molecule of heredity - DNA = phosphate group, 5 carbon sugar, nitrogenous base (A-T, C-G) - DNA is a double helix shape, proposed by Watson, Clark and Wilkinson - Runs 5' to 3' - 2 proposed types of DNA replication 1. Semiconservative: produce one molecule with one parental strand and one replicated 2. Bidirectional: parental strand stays while the other is entirely replicated 3. Dispersive: replicated DNA has fragments of replicated DNA - DNA polymerase proofreads making replication very accurate - Chargaff's rule, DNA in any species has equal amounts of Thymine to Adenine etc. - Found by Watson and Crick - Telomeres are the ends of chromosomes, short and protect chromosome ends - Avery, McLoed and McCarthy found DNA to be genetic material as it was the only material still present in their experiment - DNA was known to be helix as it diffracts X-Rays - DNA is stabilized by Hydrogen bonds - DNA is runs 5' to 3' and 3' to 5', this creates, - Leading strand: 5' to 3' DNA polymerase works with, only needs one RNA primer - Lagging strand: 3' to 5' DNA polymerase works opposite, creates Okazaki fragments - Process of DNA replication: 1. DNA helicase "unwind" protein. Creates fork of replication 2. Single-strand binding proteins prevent the substance from rebinding 3. DNA primase creates short strand of RNA so that DNA polymerase can begin 4. DNA polymerase replicates DNA, incoming dNTP create the needed energy 5. A special DNA polymerase will remove RNA primers 6. DNA ligase goes on to glue the DNA together on the lagging strand, remove Okazaki - Topoisomerases are enzymes that catalyze changes in the way DNA is arranged - Telomerase to prevent the natural shortening of DNA that polymerase causes, lengthens 3' - Adenine and guanin are purines, they are double ringed \| thymine and cytosine are pyrimidine, they are single ringed \| Gene Expression at the Molecular Level \| Summary \| - Gene Expression, the process in which genes are made into functional protein - Mutation, a heritable change in genetic material - Garron called this the inborn error of metabolism - Beadle and Tatum worked off this proposing every single step is done by a different enzyme - DNA RNA Amino Acid Protein - Gene, organized unit of DNA - Protein-Coding Genes transcribe to produce mRNA, specifies amino acid sequence - The Three Steps of Transcription 1. Initiation: Promotor + Sigma Factor bind RNA polymerase and unwind DNA 2. Elongation: Slides along DNA 3' to 5' direction, create RNA 5' to 3' direction - Binds to template strand, makes copy of coding strand, but (U = T) - Doesn't need a primer, but doesn't proofread 3. Termination: After reaching terminator RNA polymerase unbinds - RNA has a 5' cap (7-methylgunaosine) and 3' poly A tail - Exons: contain the RNA used in mRNA, Introns: not transcribable, spliced (snRNPs) - Genetic coding, 3 nucleotide base groups make up the amino acid, 64 different combinations - Start codon initiates, runs 5' to 3', stop codon ends - tRNA creates amino acid sequences, by anticodon and clover structure - amino-acid bind to ATP and tRNA synthase, ATP released, tRNA binds to synthase - Ribosome where translation takes place - Eukaryotes, 40S + 60S = 80S \| Prokaryotes, 30S + 50S = 70S - Has Aminoacyl site, Peptidyl site, Exit site (APE) 1. Initiation: mRNA, tRNA and the ribosomal subunits form a complex 2. Elongation: the ribosome travels in 5' 3' synthesizes polypeptide 3. Termination: ribosome reaches stop codon all components disassemble - In Eukaryotes mRNAs do not have ribosomal binding site, position of start codon varies - Three stages of elongation + one stage in termination: - Aminoacyl tRNA with amino acid bind to A site - Peptide bond is former, tRNA with polypeptide moves to P site - Ribosome moves 5' to 3' by one codon, uncharged tRNA moves to E site then exits - Termination when a stop codon is found at the A site - Ribosomes are the sites at which information carried in the genetic code is converted to protein - Anticodon bonds to the mRNA molecule \| Membrane Structure, Synthesis and Transport \| Summary \| - Cell membranes hold the contents of the cell together, so chemical reactions can take place - Structure: phospholipid bilayer (½ Leaflet), mosaic of proteins + carbs, are semifluid - Proteins allow for transportation, three types: 1. Transmembrane: spans from one side to the other (integral) 2. Lipid Anchored: bound to one side of the bilayer (integral) 3. Peripheral: bound to other proteins - Factors affecting bilayer fluidity: - Length of the membrane, shorter tails make less contact = more fluidity - Double bonds, less interactions = more fluidity - Cholesterol, low temp=viscous, high temp=more fluidity, either temp with cholesterol=ordered - Membranes are selectively permeable, transportation methods are: - Passive=no energy, (simple diffusion=by self, facilitated=with protein) active=energy - Membrane gradient, always maintained - Movement of water across membrane - Isotonic=identical each side, hypotonic=less on this side, hypertonic=more on this side - Crenation in animals, plasmolysis in plants - Two types of transport proteins 1. Channel, gated passageways, can be very rapid when gate is open 2. Transporters, bind to a solute and undergo a conformational change, move - Antiporters, bind to two molecules and send them in opposite directions - Uniporters, bind to two molecules and send them in the same directions - Symporters, bind a single molecule and send it trough the membrane - Active transport: - Movement across the membrane against the gradient - Primary, uses energy directly to transport - Secondary, uses an existing gradient to drive transport to another solute - Na^+^ / K^+^, exports sodium and imports potassium, both against the gradient (antiporter) - 3 Na^+^ from inside the cell binds to cytosol and ATP is hydrolyzed - Na^+^ is released outside the cell - 2 K^+^ binds from outside the cell - P is release, and K^+^ our launched into the cytosol