1 / 14

Chapter #26

Chapter #26. Inheritance of Traits. Chapter 26.1 Notes. Genetics is the study of how traits are passed from parents to offspring. Body cells have 2 of each chromosome. Sex cells have 1 of each chromosome (sperm and egg).

claudia-mcintyre
Download Presentation

Chapter #26

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter #26 Inheritance of Traits

  2. Chapter 26.1 Notes • Genetics is the study of how traits are passed from parents to offspring. • Body cells have 2 of each chromosome. • Sex cells have 1 of each chromosome (sperm and egg). • Gene is a small section of chromosome that determines a trait. Example eye color, hair color, ear shape.

  3. Human TraitsTongue rolling- dominantWidow’s peak- dominantFree ear lobe- dominantAttached ear lobe- recessiveHitch-hiker’s thumb- recessiveBent little finger- dominant

  4. Dominant genes that keep other genes from showing their traits. • Pure dominant or homozygous dominant (FF) has 2 dominant (BIG) genes. • Pure recessiveor homozygous recessive (ff) has 2 recessive (lower case) gene • Heterozygous (Ff) 1 dominant gene and 1 recessive gene.

  5. Chapter 26.2 Notes • Punnett square is a way to show which genes can combine. • Gregor Mendel- 1865 Austrian monk who studied the genetics of pea plants “The father of Genetics”.

  6. Genotype is the actual genetic make up of an organism…the letters (TT, Tt, tt) • Phenotype is what the organism look like (TT=tall, Tt=tall, tt= short) • Monohybrid cross only 1 trait at a time is crossed (4 squares)

  7. Example • In pea plants tall height is dominant to short height. If you cross a pure recessive short plant and a heterozygous tall plant what are the genotype and phenotype???

  8. In pea plants tall height is dominant to short height. If you cross a pure recessive short plant and a heterozygous tall plant what are the genotype and phenotype??? • Step #1, write the key for the letters. • T= tall • t= short

  9. In pea plants tall height is dominant to short height. If you cross a pure recessive short plant and a heterozygoustall plant what are the genotype and phenotype???Step #2, figure out each parents letters • T= tall • t= short • Parent #1 tt • Parent #2Tt

  10. In pea plants tall height is dominant to short height. If you cross a pure recessive short plant and a heterozygoustall plant what are the genotype and phenotype???Step #3, Draw the punnett square t t T= Tall t= short Tt T Tt t tt tt

  11. In pea plants tall height is dominant to short height. If you cross a pure recessive short plant and a heterozygoustall plant what are the genotype and phenotype???Step #4, Figure out the geno and phenotypes Genotype Tt=2 and tt=2 Phenotype Tall=2 and short =2 t t T= Tall t= short T Tt Tt t tt tt

  12. Dihybrid cross is when 2 traits are crossed at the same time (16 squares) • Example in pea plant round and yellow seeds are dominant over wrinkled and green seeds. If a pure dominant round, yellow seed plant is crossed with a pure recessive wrinkled, green seed plant are crossed what are the geno and phenotype?

  13. Work Cited “Mouse Genes”. April 18, 2007. http://www.uga.edu/srel/kidsdoscience/images/genetics-puppets.gif “Cartoon”. April 18, 2007. http://www.cartoonstock.com/newscartoons/cartoonists/bgr/lowres/bgrn968l.jpg “Mendel”. April 19, 2007. http://www.micro.utexas.edu/courses/levin/bio304/genetics/mendel.gif “Mendel Cartoon”. April 19, 2007. http://eebweb.arizona.edu/courses/ecol320/Mendel'sPeaSoupSmall.jpg “Punnett square”. April 19, 2007. http://www.usd.edu/med/som/genetics/curriculum/fig1-13.JPG

More Related