BIO Test 4 Notes PDF

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Summary

Notes for Dr. Crump’s test 4 covering chapters 14-17, which include the answers to the questions given in the PowerPoints, (i.e Phenotype, Mendel’s law of independent assortment, Epistasis, Replication bubble, Deoxyribonucleic acid (DNA), RNA Polymerase) ...

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Ch.14 Gene – an inherited factor that determines a characteristic, can have more than one version (an allele), each gene occurs at a specific point on a chromosome (at a locus) Genotype – set of alleles that an individual has Phenotype – the traits that an individual displays as a result of their genotype Haploid – an organism that has one copy of each gene, like E. Coli Diploid – an organism that has two copies of each gene, like humans Homozygous – the individual has two of the same alleles at a locus Heterozygous – the individual has two different alleles at a locus Mendel predicted a 9:3:3:1 ratio for dihybrid crosses Mendel’s particle theory of inheritance – which states that hereditary traits act like particles, units, or factors as they are passed from generation to generation Mendel’s law of segregation – which states that his hereditary factors do not blend but remain distinct during breeding—thus, disproving the blending theory Mendel’s law of independent assortment – which states that character traits are not connected but are inherited independent of one another. This law was soon to be modified Multiplication rule – the probability of two or more independent events can be calculated by multiplying their individual probabilities

Ch.15 Epistasis – The presence of a one allele at one locus affects a second, distinct allele at a different locus, a recessive gene can over power a dominate in some situations like ee is yellow Bb is black and in Bbee the color will be yellow Pleiotrophy – When one gene has multiple affects on different phenotypes Codominance – When both genes are expressed as phenotypes, like blood types Autosomal – does not occur on the sex chromosomes, can either be autosomal dominant or autosomal recessive Sex-linked – will be attached to the sex chromosomes, will b male or female bias

Carrier – an individual that has a copy of the gene, but does not show the phenotype (i.e., a heterozygous individuals) Aneuploidy – the presence of an abnormal number of chromosomes in a cell Klinefelter syndrome – a male with an extra copy of X - XXY Supermale – XYY - normal phenot Superfemale (trisomy X) – XXX – normal development but have higher risk of learning disabilities Turner syndrome (monosomy X) – sterile as sex organs do not develop properly Monosomic – Lacking a copy of a chromosome Trisomic – Has an extra copy of a chromosome Down Syndrome – extra copy of 21

Ch.16 Deoxyribonucleic acid – has deoxy in it because the H atom at the bottom (with the box around it) doesn’t have an oxygen with it like the other

phosphate groups have negative charge, so they cannot supercoil DNA bases Adenine and Thymine, Cytosine and Guanine Carbon attached to base is 1st prime carbon, H alone is 2nd, OH is 3rd, CH2 attached is 4th, CH2 itself is 5th https://www.youtube.com/watch?v=-K8Y0ATkkAI https://www.youtube.com/watch?v=TNKWgcFPHqw Replication bubble – area where the two parental strains are separated and undergoing replication Replication fork – a Y-shaped region where the parental strands of DNA are being unwound

Helicases – untwist the double helix at the replication fork, separating the two parental strands Single stranded binding proteins – bind to unpaired DNA strands, keeping them from repairing Topoisomerase – helps to relieve the strain on the double helix by breaking and rejoining DNA ahead of the replication fork Primase – lays down a short 10-15 nucleotide RNA primer that acts as a template for DNA replication (called a primer), this is a strand of RNA not DNA Okazaki fragments – form on the lagging strand because it is not continuously made like the leading strand DNA ligase – seals gaps between Okazaki fragments by forming covalent bonds between them

Ch.17 How DNA codes are expressed Transcription – DNA -> RNA, mostly similar language, like a rewrite Translation – RNA -> Protein, different language, like translating it In prokaryotes Transcription and translation occur in the cytoplasm RNA is made of =

notice how it has an OH in the box and not just an H like DNA RNA is signal stranded RNA bases Guanine, Cytosine, Uracil, Adenine RNA Polymerase recognizes a specific sequence in the DNA (promoter), this causes the DNA to melt and mRNA can be formed on it, the mRNA strand begins with 5’ and ends with 3’, so it moves on the opposite for DNA 3’ to 5’ Ask about which direction the polymerase moves in, and how it affects where the mRNA forms Preparing mRNA – adds a 5’ cap made of modified guanine nucleotide, adds a Poly A Tale made of 50-200 adenine nucleotides to 3’ end, removes intron or areas that don’t matter through RNA splicing

tRNA moves from 5 to 3, always starts at AUG and ends with UAA, UAG, or UGA Chaperones – protein that folds the protein that are made Ribosome – binds to mRNA with the EPA parts, starts in P then more come into A and then move out of E...