Bio 1000 Final Study Guide Kearley PDF

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Final Exam study guide for BIOL1000 with Professor Kearley. ...

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Bio Final Study Guide

New Material X Linked Pedigree: a male gets his X from one of his mother’s two X’s and a Y from his father. A female gets an X from her father and one of the two X’s from her mother {X linked genes are never passed down from father to son}  An affected female must have an affected father  All daughters of an affected male and normal female are affected. All sons of an affected male and normal female are normal  Hemophilia: blood clotting disorder  Colorblindness: mom can only give to daughter; dad can only pass down Y gene Chapter 24- Chromosomal Basis of Inheritance A. Aneuploidy- 1 more or 1 fewer chromosomes than normal 1. Many miscarriages are aneuploids 2. Downs syndrome- extra chromosome where 21st pair of homologous chromosomes is normally located B. Nondisjunction- chromosome pairs or sister chromatids fail to separate-causes abnormal number of chromosomes in gametes C. Changes in the number of sex chromosomes: 1. Kleinfelter syndrome- XXY- individual is usually sterile, feminine characteristics 2. Males with XYY- usually taller 3. Females with XXX- Meta females- limited fertility 4. Turner’s Syndrome- X0 (0=no chromosome) sterile, short stature, webbed neck Chapter 25- DNA structure and Function A. DNA (deoxyribonucleic acid)- polymer composed of nucleotides B. Nucleotides- phosphate group, nitrogenous base, 5-carbon sugar C. The structure of DNA consists of two polynucleotide strands wrapped around each other in a double helix D. DNA=4 bases- adenine, guanine, cytosine, and thymine E. Each base pairs a complementary partner 1. A-T 2. G-C F. DNA replication (makes DNA for cell division) 1. Each parent strand remains intact- template 2. Every DNA molecule is half old and half new 3. Each old strand serves as a template for a new strand G. Enzymes in replication 1. Enzymes unwind the new strand 2. DNA polymerase attaches complimentary nucleotides 3. DNA ligase joins ligaments on lagging strand H. There is continuous (leading strand) and discontinuous assembly (lagging strand) I. DNA- contains instructions for how to build proteins J. RNA-

1. Messenger RNA (mRNA)- carries protein-building instructions from the nucleus to the ribosome 2. Transfer RNA (tRNA)- delivers amino acids to the ribosome 3. RNA is also a nucleic acid 4. RNA has a uracit (U) instead of a thymine (T) K. To produce proteins 1. The DNA is transcribed to form an m-RNA in the nucleus the m-RNA travels to the ribosome 2. At the ribosome, RNA is translated to form polypeptide chains that make up proteins L. Transcription- single strand of m-RNA is formed from a DNA template M. Codons- composed of 3 nucleotide bases found on the m-RNA, these “triplets” of bases code for specific amino acids= genetic code 1. 61 different codons code for amino acids 2. 3 are stop codons N. Translation (happens in every cell of the body) 1. tRNA’s attach to amino acids in the cytoplasm and bring them to the ribosome 2. tRNA’s have base triplets called anti-codons that complement the codons found on mRNA 3. tRNA’s attached to the amino acids bind to the mRNA strand bringing the amino acid to the ribosome in the process 4. Amino acids are strung together to make polypeptides that compose proteins O. Cancer, genes, and DNA 1. Oncogene- gene that causes cancer (uncontrolled growth of cells) 2. Proto-oncogene- normal gene that can be converted to become an oncogene 3. Mutations in the DNA of proto-oncogenes cause them to become oncogenes 4. Tumor suppressor genes- normally inhibit uncontrolled cell division 5. Mutation in the DNA of tumor suppressor genes may disrupt function, allow for uncontrolled cell division 6. Multiple mutations are required to produce a cancer cell 7. Carcinogens- cancer causing agents 8. Changes in DNA often result from long-term exposure to mutagens (carcinogens) Chapter 26- Biotechnology Gene expression- the process through which genetic information flows from genes to proteins- turned off and on b turning transcription off and on A. Cellular differentiation- cells become specialized in structure and function in the many divisions that lead from a unicellular zygote to a multicellular organism 1. Most cells have a nucleus and retain a complete set of genes 2. The structure and function of a cell is dictated by the genes that are turned on in the cell B. Clone- genetically identical copy 1. Some clones in nature EX: aspen trees, strawberries 2. Some created by humans EX: Dolly the Sheep, 1st clone from a differentiated cell

3. Dolly the Sheep- exact genetic replica of another sheep a. Cell was taken from the udder of one sheep and the egg from another sheep was used, but the nucleus was removed from this egg (No DNA) b. The egg and the udder cell were fused together using an electrical stimulus- mimicked the stimulation provided by sperm when it enters the egg c. Fused cell develops as an embryo- implanted into surrogate mother that gave birth 4. Scientists may clone livestock w/ desirable traits- cattle have been produced from the cells from a side of beef 5. Reproductive cloning in humans? Clone exact genetic copy of a human 6. Cloning and use of DNA could also be used to: increase numbers of species, bring back extinct species C. Embryonic stem cells- eventually gives rise to all the specialized cells in the body 1. Therapeutic cloning- transplant nucleus from patients cells into developing embryonic stem cells and then harvest the stem cells at a very early age. Stem cells then used to replace damaged cells *Adult stem cells= not as easy to culture D. Adult stem cells can also perpetuate themselves in culture and give rise to differentiated cells 1. They are harder to culture than embryonic stem cells 2. Give rise to only a limited range of cell types in contrast with embryonic stem cells E. Homeotic genes program the development of organisms F. Tools and processes used for cutting the DNA and producing recombinant DNA 1. Restriction enzymes- found in bacteria- used to cut DNA 2. Transformation- bacteria- pick up DNA from surroundings 3. Plasmids- rings of bacterial DNA that can be incorporated into the bacterial cell 4. Scientists use restriction enzyme to cut a gene out of the human DNA, then the same enzyme is used to make a cut in the DNA of a plasmid 5. Fragments from human genes will fit into plasmids of bacteria like a piece of puzzle 6. Bacteria then take up the plasmids containing the human genes and replicate- turning out collective quantities of the desired protein a. Ex: somatotropin- growth hormone normally secreted by the pituitary gland b. Faulty pituitary gland will result in abnormally short individuals c. Gene that produces somatotropin was snipped out of the human genome and inserted into E. coli bacteria d. Each gene is then transcribed and translated to produce collectible quantities of somatotropin 7. Recombinant DNA- 2 sections of DNA that have been combined by humansdoes not exist in nature H. Techniques for evaluating and replicating DNA 1. Gel electrophoresis- sorts proteins and nucleic acids by charge or size

2. Polymerase chain reaction (PCR)- DNA is mixed with DNA polymerase (enzyme_ and nucleotides which allow the DNA to replicate a. Can be used for replicating DNA in fossils and artifacts, for medical purposes, and DNA found at a crime scene I. Human Genome- genome consists of the entire genetic makeup of an individual 1. Human genome project- finished in 2000 J. Biotechnology and food production 1. In U.S, 45% corn and 85% soybeans are genetically modified 2.Inserted a version of growth hormone gene into salmon that causes them to grow 500% faster 3. Gene from Bt bacteria inserted into the DNA of plants- provides resistance against insects Chapter 27- How populations evolve -Evolution: the modification of populations of living things overtime- can result in a new species -Species: individuals that can interbreed with one another and produce offspring that can also reproduce A. Natural Selection- those organisms better adapted to their environment will be more likely to survive and pass on their traits to future generations B. Fitness- measure of reproductive success: the fittest individuals are those that leave the most decedents 1. For selection to be an agent of evolutionary change, the traits considered must a. Vary b. Be heritable c. Affect fitness C. Organisms come from ancestral species 1. Evolution is dynamic- very slow 2. Life forms (populations) are constantly changing 3. Advances in genetics, taxonomy, paleontology, comparative anatomy etc. all lent support to this theory 4. Evolution= unifying principle of biology D. The fossil record shows that organisms have appeared in a historical sequence E. Comparative morphology and embryology 1. Morphology- study of the physical forms that organisms take 2. Homologous features- same in structure b/c of inheritance 3. Embryology- study of how organisms develop from fertilization to birth F. Evidence from molecular biology 1. Universal triplet code (DNA) suggests that different species evolved from common ancestor 2. Mutations can cause DNA to change slowly over time EX: gene that codes for cytochrome C G. Microevolution 1. Populations evolve, individuals do not 2. Gene pool- all the alleles that exist in a population

3. Microevolution- change in allele frequencies over time 4. Five agents of Microevolution: a. Mutations- permanent alteration in an organisms DNA 1. For mutations to affect evolution, they must her heritable 2. Rate of mutation is low- most mutations neither harmful nor beneficial 3. Mutation is the only means by which new genetic information is introduced b. Gene flow- movement of genes from one population to another - Occurs through migration c. Genetic drift- the chance alteration of allele frequencies in a population 1. Bottleneck effect: change in allele frequencies due to chance during a sharp reduction in a pop.’s size EX: Northern elephant seals- #’s dropped to 50 animals b/c of commercial harvest 2. Founder affect: when a small subpopulation migrates to a new area EX: Pingleap- Micronesian island where 10% of the population is completely colorblind d. Nonrandom mating- mating in which a given member of the population is not equally likely to mate with any other given member EX: 4 females, 4 males- 1 male breeds with all of the females e. Natural selection- the only one of the 5 agents that consistently works to adapt organisms to their environment, considered the most important agent in having shaped the natural world *Most important agent in evolution Chapter 33-37- Ecology and Conservation -Ecology= the study of the interaction of living things with one another and their environment -Ecosystem= all the organisms in a given area and the non living factors with which they interact -Biodiversity= the variety of living things; includes genetic diversity, species diversity, and ecosystem diversity A. Interactions among living organisms 1. Competition (-,-) negative interaction 2. Predation (+,-) positive/negative [prey dies] 3. Parasitism (+,-) positive/negative [host wont die] 4. Mutualism (+,+) Positive interaction 5. Keystone species- species whose influence on a community is greater than its abundance would suggest B. Pathways of energy and nutrients 1. Autotrophs capture 3% of the suns energy that reaches the surface of the Earth.... (it asks which of these things th 2. Energy pyramids C. Conservation of biodiversity

1. Growing human and consumption must be brought into balance with conserving ecosystems and the organisms that live there 2. Primary threats to conservation: a. # 1 threat to conservation of biodiversity in habitat destruction b. Commercial harvest: harvesting of animals/plants for money c. Introduction of exotic species 3. Possible solutions 1. Live sustainably 2. Education- emphasize benefits of biodiversity 3. Create reserves and protected areas

Old Material Chapter 1 Atomsmoleculesorganellescellstissuesorgansorgan systems Chapter 2- Chemical Basis of Life -An atom is a basic unit of matter composed of protons, neutrons, and electrons  Nucleus contains all the mass (protons and neutrons)  Protons determine the atomic # and have positive charge  Neutrons have no charge - Ion: atoms that differ in # of protons and electrons, always + or – charged atom - Isotope: forms a single element that differ in the # of neutrons Bonds- covalent [atoms share electrons], polar covalent [creates – charge on one end of nucleus], hydrogen [+ end is attracted to – end], ionic [atoms bond through oppositely charged particles] -Hydrophilic and Hydrophobic molecules - Acids and bases  Monomer: single unit o Monosaccharide, fatty acids, amino acids, nucleotide  Polymer: string of monomers o Carbohydrates (starch) o Lipid o Protein o Nucleic acid - Dehydration synthesis and hydrolysis Chapter 3- Cells - Differences and similarities b/t prokaryotic and eukaryotic cells - Cell organelles and functions of each - Components of the cytoskeleton - Plant vs. Animal cells Chapter 4- Cell Membrane -Plasma Membrane and cell membrane -Diffusion

 Osmosis, hypertonic, hypotonic Chapter 6- Metabolism, Energy, and Enzymes -Metabolism: sum of all chemical reactions that an organism carries out -Energy: ability to do work (bring about movement against opposing force)  Exergonic reactions: release energy (reactants have more energy than the products)  Endergonic reactions: require energy (products have more energy than the reactants) -Enzymes: proteins that speed up chemical reactions and lower the amount of energy required to start chemical reactions Chapter 7- Respiration -We undergo cellular respiration to make ATP= main goal  Aerobic respiration- aerobic harvesting of energy from molecules by cells. *use oxygen  Krebs cycle  ETC (make most of the ATP)  Glycolysis  Anaerobic Respiration: *does not use oxygen, produces less ATP, products produced from anaerobic respiration include lactic acid and alcohol Chapter 8- Photosynthesis -Autotrophs: produce their own food -Structure in plants: chloroplasts, thylakoid, Grana, Stroma, stromata, pigments, chlorophylls -Light dependent reactions, light independent reactions Chapter 5- Mitosis and Meiosis *read over study guide and notes Chapter 23- Genetics -Mendel crossed pea plants His hypothesis: there are alternative forms of genes= alleles, for each characteristic an organism has 2 genes, one from each parent, a sperm or egg carries only one allele for each, dominant and recessive alleles  If Y= yellow seeds, y= green seeds, the Yy= yellow seeds  Homozygous= YY or yy  Heterozygous= Yy (1 dom and 1 recessive allele)  Phenotype= physical traits  Genotype= genetic makeup  P= parental generation  F1= first generation of offspring  F2= 2nd generation of offspring (grandkids of P)  Monohybrid cross= evaluate 1 trait  Dihybrid= evaluate 2 traits  Incomplete dominance: when two traits mix o R=red, r=white Rr= pink  Codominance: the expression of 2 different alleles of a gene in a heterozygote (both genes are dominant) 1. ABO blood type (codominance)

a. two alleles (1a+1b) are codominant b. third allele (i) is recessive to others - Pleitrophy: alleles at a single locus may have effects on 2+ traits -Polygenic traits- traits affected by genes at more than one loci 1. Continuous variation- continuous range in a given trait among individuals 2. The more genes a trait is affected by, the more continuous the variation -Autosomal recessive inheritance: two recessive alleles must be present for the trait to be displayed 1. recessive disorders-parents must be carriers EX: Albinism, Sickle cell anemia, and cystic fibrosis - dominant disorders- carried out on dominant alleles o EX: Achondoplasia, Huntington’s disease - Y Chromosome o Contains master gene for sex determination, if present testes form o Contains very few genes - X chromosome o More genes than Y chromosome, many deal with nonsexual traits o Genes in X chromosome can be expressed in both male and female -X-linked inheritance o Trait is carried on the X chromosome o Appears in males more than females, male can not inherit from his father EX: colorblindness, hemophilia...