Genetics Topic 17

Chromosome Polymer Gene Heredity DNA Ribosome RNA Transcription Vocabulary: Chromosome Polymer Gene Heredity DNA Ribosome RNA Transcription Nucleotide Translation Gamete

Can you roll your tongue? Do you have a widows peak? Clasp your hands. Is the right or left thumb on top? Do you have dimples? Do you have a hitchhikers thumb?

Genetics The study of heredity Heredity- transfer of genes from parents to offspring

Gregor Mendel “Father of Genetics” 1800’s Studied heredity in pea plants

100 Greatest Discoveries: Genetics: http://science. discovery

Which type of reproduction leads to more variation?

Reproduction Genetic material is passed to the next generation

DNA Deoxyribonucleic Acid Contains all genetic information Located in Nucleus

Gene Small section of DNA Codes for a specific trait

Chromosome Contains several genes

Gene Chromosome Theory

Chromosomes

DNA Deoxyribonucleic Acid Organic Molecule Double stranded

Structure of DNA Shape = Double Helix or “twisted ladder” Discovered 1953 Watson & Crick made first model

Watson & Crick

Franklin & Wilkins

Structure of DNA Polymer- long chain of repeating nucleotides

Nucleotide Contains: Phosphate group Deoxyribose (sugar) Nitrogenous bases (Adenine, Thymine, Cytosine & Guanine)

Draw this diagram!!!!!! Phosphate Nitrogenous Base Deoxyribose

The Structure of DNA: http://www.youtube.com/watch?v=qy8dk5iS1f0

Complementary Bases Adenine (A) ONLY pairs with Thymine (T) Cytosine (C) ONLY pairs with Guanine (G) A-T C-G

If you know the bases on one strand of DNA, you can determine the other strand

DNA Replication DNA makes a copy of itself before MITOSIS http://www.youtube.com/watch?v=hfZ8o9D1tus

DNA Replication DNA unwinds DNA unzips Strands from original DNA called Template Strands New bases pair with template strands

Replication Results Each new DNA contains one template strand and one new strand

Mutations Change in the sequence of bases. Changes the genetic code.

Original DNA Template: Types of Mutations Original DNA Template: CACCGTATTA Substitution: one base for another CACCTTATTA Deletion: missing a base CACCG_ATTA Addition: adding a base CACCGTAATTA Inversion: bases are rearranged CACCTAGTTA

Mutations

What causes mutations? Exposure to radiation Exposure to chemicals Nuclear, UV, x-rays Exposure to chemicals Nicotine, asbestos

When are mutations passed on? Mutations which occur in the sex cells will be passed on to offspring.

DNA vs. RNA DNA RNA

DNA RNA Double Stranded Sugar- Deoxyribose Thymine (T) Too big to leave nucleus Single Stranded Sugar- Ribose Uracil (U) Small enough to leave nucleus

3 Types of RNA Messenger (mRNA) Transfer (tRNA) Ribosomal (rRNA)

mRNA Only 1 gene long! Made during a process called TRANSCRIPTION http://www.youtube.com/watch?v=OtYz_3rkvPk&feature=related

Making mRNA DNA template needed RNA polymerase (enzyme) unwinds DNA mRNA forms from complementary bases

More Transcription http://www.youtube.com/watch?v=ztPkv7wc3yU&feature=related

mRNA’s Job Carry the code for building proteins from the nucleus to the ribosome.

Ribosome Site of TRANSLATION Using the mRNA sequence to build a protein

Codon 3 base codes Code for a specific amino acid Amino acids make proteins! AUC GAC UAG CUA

tRNA Reads the mRNA codons Anticodon part of the tRNA that reads the codon Translates (tells) which amino acid is needed

tRNA

Building a Protein http://www.youtube.com/watch?v=NJxobgkPEAo

When a STOP codon is reached the protein is complete www.wisc-online.com/objects/index_tj.asp?objID=AP1302

Codon Chart

BIOTECHNOLOGY

Selective Breeding Choosing which animals or plants should be breed Creates offspring with desirable traits

Brahman cattle: Good resistance to heat but poor beef. English shorthorn cattle: Good beef but poor heat resistance. Santa Gertrudis cattle: Formed by crossing Brahman and English shorthorns; has good heat resistance and beef.

Lion + Tiger = LIGER

Labrador + Poodle= LABRADOODLE

Genetic Engineering Recombinant DNA Cut or copy a section of DNA with an enzyme Add that gene to the DNA of another organism Organism will express traits from the new gene

Cloning

Steps of Cloning Take a parent cell nucleus & remove it Take an egg cell from a female and remove the nucleus Take the nucleus from the parent cell and put it into the egg cell Implant the egg cell into a female for development

Cloning of Dolly http://video.google.com/videoplay?docid=246187639814358296#http://video.google.com/videoplay?docid=246187639814358296#

Mapping Genes If we know what each gene does, we can see what diseases or disorders we may have.

Human Genome Project Began 1990 Goal: understand what every gene in human body does

Gene Therapy “Bad” genes can be replaced with “good” genes

DNA Fingerprinting

DNA & Protein Synthesis Activity: http://www. pbs Create a DNA Fingerprint Activity (Parts 1-3): http://www.pbs.org/wgbh/nova/sheppard/analyze.html

Karyotype Picture of chromosomes Can be used to diagnose genetic disorders

Normal Male

Female- Trisomy 21

Genetic Counseling Family history of genetic disorders What are the chances that the disorder will be passed on?

Gene Expression Environmental factors can turn genes on or off.

Himalayan Rabbit

Mutations

Genetic Disorders Mutations, incorrect DNA sequences, can be passed to offspring only if they occur in the gametes!

Osteogenesis Imperfecta (fragile bones)

Color Blindness

Albinism

Polydactyly

Dwarfism

Images http://kentsimmons.uwinnipeg.ca/cm1504/Image268.gif http://library.thinkquest.org/18617/media/replication-simple.gif http://evolution.berkeley.edu/evosite/evo101/IIIC3Causes.shtml http://www.picture-newsletter.com/nuclear/nuclear-power-plant-9igh.jpg http://admin.moguling.com/Upload/nutritionalsupplementsskincreams.com/sun.jpg http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/9939.jpg http://stemcells.nih.gov/StaticResources/info/scireport/images/figurea6.jpg http://www.daviddarling.info/images/tRNA.gif http://visual.merriam-webster.com/animal-kingdom/carnivorous-mammals/dog-breeds_2.php http://theos.in/science/what-do-lions-eat-an-elephant/ http://www.solarnavigator.net/animal_kingdom/mammals/tigers.htm http://www.naturesafariindia.com/liger.html http://www.justdogbreeds.com/labrador-retriever.html http://www.allergyescape.com/labradoodle.html http://top-10-list.org/2009/04/30/ http://www.glogster.com/media/4/19/82/22/19822298.gif http://genomics.energy.gov/gallery/logos/detail.np/detail-10.html http://ghr.nlm.nih.gov/handbook/illustrations/therapyvector.jpg http://genomics.energy.gov/gallery/chromosomes/view.np/view-01.html http://www.biotechnologyonline.gov.au/popups/img_karyotype.html http://www.pbs.org/wgbh/nova/allfours/gene-04.html : http://tlc.discovery.com/fansites/lpbw/about.html