Transcription

1 Hairy Heredity Skills: Life Science, Math Ojective: Students will flip cins t demnstrate hw parents pass genetic traits t their ffspring thrugh heredity and the difference etween dminant and recessive genes, and hw they interact. ackg Agriculturalists have pineered the study f genetics and heredity. Fr centuries farmers and ranchers have selected plant varieties and livestck fr specific traits. Plant reeders select plant varieties which prduce mre seed r fruit. Livestck prducers select animals with specific traits such as increased milk prductin, ample muscle mass r structural crrectness. Selecting fr these traits has allwed agriculturalists t prduce a higher quality and mre aundant fd supply. Heredity is the passing n f traits frm parents t ffspring. Mst plants and animals have tw f every kind f gene, ne frm their mther and ne frm their father. Only ne gene frm each parent is passed t each ffspring fr a particular trait. There are different frms f a gene that are referred t as alleles. Alleles are frms f the same gene with small differences in their DNA sequence. These small differences cntriute t each persn's unique physical features. Sme alleles are dminant while thers are recessive. Dminant genes verpwer recessive genes and are always expressed in ffspring. ecessive genes are nly expressed in ffspring if th parents cntriute a recessive gene. In human eye clr, the gene fr rwn eyes is dminant and the gene fr lue eyes is recessive. Therefre, if the ffspring receives a rwn eye gene frm either parent, the ffspring will have rwn eyes. The ffspring wuld have t receive a lue eye gene frm each parent t have lue eyes. The fllwing diagram is a Punnett square which illustrates all the pssile cminatins f tw gene sets and and the resulting genetic traits. is the dminate gene fr rwn eyes is the recessive gene fr lue eyes. Punnett square xes shw the pssile cminatins f genes that an ffspring may receive frm its parents. Punnett Square P.A.S.S. Grade 5 Science Prcess 2.1; 4.1,2; 5.3 Math 2.1cd,2a Grade 6 Science Prcess 2.1; 4.1,2; 5.3,4 Math Prcess 1.6; 2.1; 4.1 Math 5.1 Grade 7 Science Prcess 2.1; 4.1; 4.2; 5.3 Life Science 3.1, 2 Math 2.2c; 5.1,3 Parent s Eye Clr (rwn Gene) (lue Gene) (Dminant Trait) = rwn Eyes = rwn Eyes (ecessive Trait) = rwn Eyes = lue Eyes

2 Vcaulary agriculturalist smene invlved in the science, art, and usiness f cultivating the sil, prducing crps and raising livestck. allele ne f tw r mre alternative frms f a gene that cntrls the same inherited characteristic. DNA (dexyrinucleic acid) mlecule that cntains genetic infrmatin and is lcated in the nucleus f every cell inside an rganism. gene The asic unit f heredity that serves as a lueprint fr each prtein prduct prduced in the human dy; humans have ver 30,000 genes. heredity the passing n f traits frm parents t ffspring. Punnett Square diagram used y scientists t help them t figure ut hw inherited traits (characteristics) will e distriuted. trait an inherited distinguishing feature r characteristic f an rganism. Praility is the chance that smething will happen. Using the ave Punnett square x, there is a 75 percent chance f an ffspring having rwn eyes if th parents have th dminate and recessive genes. There is a 25 percent chance f the ffspring having lue eyes. This simple illustratin demnstrates hw the genetics f ne gene functins. Humans, plants and animals have multiple genes which have cmplex interactins t determine ffspring traits. Math and Science 1. rainstrm t find student knwledge f the transfer f genetic traits frm parents t ffspring. Share ackg material. 2. Give each student a cpy f the activity wrksheet and a cin. Instruct students t flip the cin t determine which traits the mther will pass n t her ffspring. If the cin lands n heads, the students shuld circle the dminant trait. If the cin lands n tails, the students shuld circle the recessive trait. Have students repeat this prcess fr all eight traits frm the mther and father. Once all the traits have een randmly selected frm the mther and father, transfer the selected traits t the Genetic Trait Wrksheet. Circle the apprpriate genetic trait which will e expressed in the ffspring. 3. Hand ut the Smiley Face Wrksheet, and have students draw and clr a smiley face that expresses all the randmly selected genes. Are all the faces the same? Hw are the faces different? Why? Cunt acrss the rm the numer f smiley faces with rwn eyes. Is it 75 percent f the faces, as the Punnett Square predicted? D the same fr the ther traits. 4. epeat the genetic activity and cmpare the results with this activity. Are the results the same? Is the percentage f lue eyes the same? Other traits? 5. Develp a Punnett square diagram fr the ther traits. Why is there a 50 percent chance f the ffspring eing a girl? 6.. Cmpare student s characteristics a the rm. D 75 percent f the students have rwn eyes? What percentage f student s eyes are lue r green? Oklahma Ag in the Classrm is a prgram f the Oklahma Cperative Extensin Service, 4 H uth Develpment, in cperatin with the Oklahma Department f Agriculture, Fd and Frestry and the Oklahma State Department f Educatin. Oklahma Ag in the Classrm Oklahma 4-H Prgrams H uth Develpment Oklahma State University Stillwater, OK

3 Hairy Heredity Use the flip f a cin t determine which genes yur ffspring will carry. Flip a cin t determine which genetic traits each parent will pass n t their ffspring. If the cin flip lands n heads select the dminate trait. If the cin lands n tails, select the recessive trait. FATHE S TAITS MOTHE S TAITS Flip cin and circle selected trait. heads tails dminant recessive s S f H heads tails dminant recessive s S f l H Prduced y Oklahma Cperative Extensin Service, Divisin f Agricultural Sciences and Natural esurces, OSU, inn cperatin with the Oklahma Department f Agriculture, Fd and Frestry and the Oklahma State Department f Educatin, l

4 Genetic Trait Wrksheet sample trait mther s traits T father s traits t pssile trait cminatins Circle apprpriate trait. tall TT shrt tt s square ss rwn rwn lue ig ig l smile SS val smile Sf frwn ff yellw yellw range male y female n/a hairy HH tall Tt hairy H Prduced y Oklahma Cperative Extensin Service, Divisin f Agricultural Sciences and Natural esurces, OSU, inn cperatin with the Oklahma Department f Agriculture, Fd and Frestry and the Oklahma State Department f Educatin, little ll ald

5 Smiley Face Wrksheet / square Draw and clr the ffspring s smiley face Add details t identify yur smiley as a y r girl. / val rwn / lue smile / frwn ig / little yellw / range hairy / ald y / girl ffspring s name Prduced y Oklahma Cperative Extensin Service, Divisin f Agricultural Sciences and Natural esurces, OSU, inn cperatin with the Oklahma Department f Agriculture, Fd and Frestry and the Oklahma State Department f Educatin, 2005.