Heredity

We know that traits are inherited, but how? What characteristics do you have in common with your parents? Your grandparents? If you have siblings, what characteristics do you have in common with them?

Take a look at yourself… Image from: http://sivers.org/you-not-them

Dominant or Recessive?

Cheek Dimples cheek dimples are dominant Image from: http://www.ncrtec.org/tl/camp/gene/dimples.htm

Brown/black eyes? brown/black eyes are dominant over blue/green eyes

Attached Earlobes? attached earlobes are recessive

Widow’s Peak? pointed hairline is dominant over straight hairline Image from: http://www.thetech.org/genetics/ask.php?id=148

Hitchhiker’s thumb? a straight thumb is dominant over a bent thumb Image from: http://www.funfacts.com.au/inhererited-characteristicstraits-aka-can-you-roll-your-tongue/

Tongue roller? the ability to roll your tongue is dominant Image from: http://forum.saxontheweb.net/showthread.php?137222-Tongue-rolling-and-playing

Left thumb on top? when you fold your hands, the left thumb on top is dominant over the right thumb on top Image from: http://www.123rf.com/photo_351940_a-homeless-man-sitting-on-ground-folding-his-hands.html

6 fingers? polydactyly is dominant Image from: http://filipspagnoli.wordpress.com/2008/04/06/human-rights-poem-27/

How are these traits inherited?

Monks are known for many things… Image from: http://www.wineandco.co.uk/dom-perignon-blanc-2000-vintage-sans-coffret-6468-uk-liv-uk.html

Gregor Mendel (1822-1884) Austrian monk did experiments with garden peas that laid the foundation for modern genetics “the father of modern genetics” http://science.discovery.com/tv-shows/greatest-discoveries/videos/100-greatest-discoveries-shorts-genetics.htm Image from: http://history.nih.gov/exhibits/nirenberg/popup_htm/01_mendel.htm

Image from: http://www. tutorvista

Image from: http://www. biology. iupui

Image from: http://www. bioinformatics

Mendel’s conclusions inherited characteristics are controlled by factors that occur in pairs one factor masks the effect of another (the principle of dominance) a pair of factors separate during the formation of sex cells each sex cell contains only one factor for each characteristic

Punnett square chart that organizes the possible combination of “factors” in offspring See this website for a simple animation on creating a Punnett square: http://www.ctahr.hawaii.edu/dnatoday/genepool/genepool%20think.html

Image from: http://childofthecornx.livejournal.com/18092.html

Image from: http://edu. glogster. com/glog. php

Questions Read 4.2 (p.134-137) and answer the following questions: #1,3 (p. 137-138)