Genetics notes
description
Transcript of Genetics notes
![Page 1: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/1.jpg)
Genetics
![Page 2: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/2.jpg)
Hemophilia
• An inherited blood disorder that slows the blood clotting process
• This means that the factors that cause the blood to clot are missing
• In the past life expectancy was age 11 but now it is only about 10 years less than average
![Page 3: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/3.jpg)
• Hemophilia is a sex linked disorder, it is found on the X chromosome
• (Remember females are XX and males are XY)
• A mother who is a carrier has a 50% chance of passing the faulty chromosome to her daughter
• An affected father will always pass on the affected gene to his daughter
![Page 4: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/4.jpg)
![Page 5: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/5.jpg)
Klinefelter’s Syndrome
• Condition in which males have an extra X chromosomes
• Most common sex chromosome disorder
![Page 6: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/6.jpg)
• Affected males usually are infertile, some degree of language learning impairment may be present, as well they may have more feminine body characteristics
![Page 7: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/7.jpg)
![Page 8: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/8.jpg)
What is the difference between sex
chromosomes and somatic chromosomes?
![Page 9: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/9.jpg)
• Sex Chromosomes: X and Y, these chromosomes code for sex characteristics
• Somatic Chromosomes: 1-22, these code for all other characteristics in the body regardless of sex
![Page 10: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/10.jpg)
Asexual Reproduction
• Type of reproduction that involves only one parent
• Produces offspring that are generally identical to the parent
![Page 11: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/11.jpg)
• Asexual reproduction is beneficial because it allows populations to continue even if their is a lack of males
• The downside is that because offspring are identical to parents, genetic variation is lacking and the population is susceptible to disease
• e.g. Bananas
![Page 12: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/12.jpg)
Sexual Reproduction
• Reproduction involving the union or fusion of a male and female gamete
• Because 1/2 of the genetic material comes from each parent there is much more genetic variation within offspring
![Page 13: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/13.jpg)
Biotechnology in our Society
![Page 14: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/14.jpg)
Recombinant DNA
• Type of DNA that is artificially created by inserting a strand or more of DNA into a different set of DNA
• Called rDNA
![Page 15: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/15.jpg)
• Used to introduce specific characteristics into different crops, bacteria and animals
• commonly used to create strains of crops that are draught resistance, etc
![Page 16: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/16.jpg)
• 1. Isolate gene
• 2. Prepare target DNA, a circular piece of DNA(called plasmid) is taken from one organism, special proteins are used to cut open the DNA
• 3. Insert DNA into Plasmid, the gene that is being inserted is put into the plasmid ring and the ring is closed again
Steps in Creating Recombinant DNA
![Page 17: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/17.jpg)
• 4. Insert Plasmid back into cell, the DNA that contains the human gene is inserted into a bacteria
• 5. Plasmid multiply, when the bacteria multiplies, whatever the new gene codes for presents itself in the new offspring
• 6. Target cells reproduce
• 7. Cells produce proteins
![Page 18: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/18.jpg)
Genetic Screening
• Process that allows for the identification of inherited diseases, paternity, mutations, etc
![Page 19: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/19.jpg)
Adult
• Can be used in presymptomatic testing for adult-onset disorders like Huntington’s or for estimating the risk of developing adult-onset cancers or Alzheimers
![Page 20: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/20.jpg)
pre-natal testing
• Ultrasound-can be used to check for abnormal development
• Amniocentesis-a sample of amniotic fluid is taken, can be used to check for Downs syndrome, neural tube defects, etc
• Karyotype-done with samples taken from amniocentesis etc
![Page 21: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/21.jpg)
Explain why you think genetic testing can have
positive effects and negative effects in a
paragraph
![Page 22: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/22.jpg)
Population Genetics
![Page 23: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/23.jpg)
deme and gene pool
• Deme-a term for an isolated population that interbreed with each other and share a distinct gene pool
• Gene pool-the complete set of unique alleles in a population
![Page 24: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/24.jpg)
• a large gene pool indicates extensive genetic diversity, this means that the population will be able to withstand disease, etc
• a small gene pool can lead to deme’s which can lead to susceptibility to certain diseases etc within that population, e.g. hemophilia in the royal family, tay-sachs in Ashkenazi jewish populations, etc
![Page 25: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/25.jpg)
Hardy-Weinberg Principle
• http://www.slideshare.net/klemmistry101/hardy-weinberg-populations
![Page 26: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/26.jpg)
Hardy-Weinberg handout
![Page 27: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/27.jpg)
Genetic Drift
• frequency of traits can change in a population due to chance events
• this is NOT adaptation to environmental conditions
• Occurs with the founder effect and bottleneck effect
![Page 28: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/28.jpg)
• Founder effect: small group splinters off and starts a new colony
• just by chance some rare alleles may be at high frequency, others may be missing
• skews the gene pool of the new population
• e.g. colonization of ‘New World’-human populations that started from small groups of colonists
![Page 29: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/29.jpg)
![Page 30: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/30.jpg)
• Bottleneck effect: when a large population is drastically reduced by a disaster i.e. famine, natural disaster, loss of habitat
• loss of variation by chance event, alleles lost from gene pool
• this narrows the gene pool
![Page 31: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/31.jpg)
![Page 32: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/32.jpg)
• Bottleneck example: Cheetahs
• all share a small number of alleles-less that 1% diversity, as if ALL cheetahs are identical twins
• 2 bottlenecks-10,000 years ago(Ice Age), last 100 years (poaching and loss of habitat)
![Page 33: Genetics notes](https://reader031.fdocuments.net/reader031/viewer/2022020716/547f2952b4af9ff0438b4754/html5/thumbnails/33.jpg)
The End.