Biology 120 Lab Exam 2 Review PDF

Preview

Summary

Download Biology 120 Lab Exam 2 Review PDF

Description

Biology 120- Lab Exam Review

Labs 5-7 Worth 15% 90 minutes 55 marks- spot test (10), short answer (45) Lab 5: Intro to Genetics  Mendel’s First Law- Alleles of one gene separate from each other in the formation of gametes  Mendel’s Second Law- Genes for different traits assort independently of one another in the formation of gametes.  Test cross- mating between an individual of unknown genotype for a particular characteristic and an individual that is homozygous recessive for that characteristic.  Independent assortment- Mendel’s Second Law, genes assort independently  Gene linkage- genes that are located less than 50 map units apart on the same chromosome and are inherited together.  Frequency- range between 0 and 1, and always add up to 1. Ex. 0.5 Dd, 0.25 DD, 0.25 dd (genotypic frequency), 0.75 green seeds, 0.25 white seeds (phenotypic frequency)  Ratio- in lowest quantity. Ex. 1 DD:2Dd:1dd (geno), 3 green seeds:1 white seed (pheno)  Monohybrid cross- is between two organisms that differ with respect to one characteristic  Dihybrid- differ in respect to two characteristics Lab 6: Human Genetics and Gene Linkage  Autosomes- The non-sex chromosomes (22 pairs in humans)  Autosomal- Refers to genes that are located on autosomes (not sex-linked)  Karyotype- Photographic representation of the chromosomes of an actively dividing cell, showing the specifics of the chromosomes.  Turner Syndrome- Only one sex chromosome X Symptoms- Short stature, non-functioning ovaries & webbed neck  Down Syndrome- three chromosomes on the 21st pair (trisomy 21) Symptoms- Almond-shaped eyes, mild to moderate mental deficiency & shorter limbs and neck  Klinefelter Syndrome- Two X sex chromosomes and one Y sex chromosome (XX Y) Symptoms- possible learning disabilities, sterile with small testes & low testosterone levels  PTC- Taster or non-taster, paper test  X-linked (sex-linked)- Genes that are passed down from parental sex chromosomes, males are more likely to exhibit sex-linked recessive traits as they only have one X chromosome. Ex. Red-green colour blindness, total colour blindness & hemophilia.  Polygenic- Phenotypic traits that involve contributions from the alleles of several or many genes at multiple locations on the chromosomes  Pedigree chart- diagram that shows the occurrence of phenotypic traits or genetic diseases in successive generations, show how traits are passed along.  Tri-radius- Y formation on fingerprints  Fingerprints- Arch, loop, whorl, and double loop

  

Recombinant- DNA molecule carrying genes derived from two or more sources Parental- Genes derived from the parental generation How to calculated map units: ( number of recombinants ÷total offspring ) ×100 %

Lab 7: Biotechnology  Step 1: DNA Extraction  Three solutions used in DNA extraction and briefly describe: 1. Isotonic solution (Gatorade)- to collect cheek cells intact without causing them to burst 2. Lysis solution (detergent)- lyses the plasma membrane by disrupting the lipid bonds that compose the membrane 3. Ethanol- DNA is insoluble in alcohol so the DNA precipitates out of the solution  Step 2: Polymerase Chain Reaction  Ingredients required for Polymerase Chain Reaction (PCR): 1. DNA extract 2. 4 dATPs 3. Primers 4. DNA polymerase  Steps in one PCR cycle: 1. DNA denaturation- heat to separate the two strands of the DNA double helix 2. Anneal primers- Cool so that primers can bond to the single strands of DNA 3. Extended primers- Heat to allow DNA polymerase to add dNTPs to the end of the primers  Step 3: Restriction Fragment Analysis  Restriction fragment analysis1. Restriction Digest- restriction enzyme is added to the PCR product and the solution is placed in the incubator. The enzyme cuts the DNA in the PCR product into specific fragment sizes and numbers, depending on the number of restriction sites present. 2. Gel Electrophoresis- allows us to separate the restriction fragments based upon molecular size differences. Smaller fragments travel farther as it is easier to move through the gel. DNA is negative.  Modern Biotechnology and how they benefit humans 1. Medicine- bacteria and yeast are used to make biosynthetic insulin and other disease-specific medicines 2. Transgenic plants- modification of plants to enable the expression of selected traits that improve nutritional value plants and resistance to plant disease, insects, pests and herbicides are commonly used in transgenic plants. 3. Transgenic livestock- genetic modification to enable expression of selected genes in mammals 4. Cloning- large scale production of genetically identical plants from somatic cells...