Get ready for : New Info GENETICS WITH A SMILE OBJECTIVES: what are we going to learn?
Define dominant and recessive traits Explain:homozygous heterozygous genotype phenotype Heres what youll be doing
Creating your Smiley Face offspring: 1.flip coins to determine their physical traits. 2. match traits on sheet to determine what your offspring look like. 3. flip coins to determine male or female. 4.sketch Smiley; in Tech class you will useWord to computer generate sketch. Remember? Genes arenot these! Where do they come from?
How many does each cell have? Where do we find them? Genes Dominant gene-one that always shows up.
Write it as a capital letter; example:B for brown hair Recessive gene-one that is hidden whenthe other copy of the gene contains adominant trait. Only shows up when thereis no dominant gene present. Write it as a lower case letter; example: b for blond hair What if? What if an offspring inherits one dominant gene from their mother and one dominant gene from their father? Example: BB for brown hair We call that being HOMOZYGOUS dominant because you have two genes that are the same. Two capital letters! Remember: Homozygous Dominant is:
Both the same trait from parents thatalways shows up use capital letter Brown hair from motherB Brown hair from fatherB What if? What if an offspring inherits onerecessive gene from their mother andone recessive gene from their father? Example: bb for blond hair We call that being homozygousrecessive. Two genes the same; uselower case. Remember: Homozygous Recessive is:
Both same trait but doesnt show upif dominant trait is present. blond hair from motherb blond hair from father b bb I know what youre going to ask!
What if an offspring inherits onedominant gene from one parent andone recessive gene from the otherparent? Example: Bb What do you think we would call this? Heterozygous Dominant!! Bb BB bb Bb So what is a genotype?
Those capital and lower case lettersyou just learned abouttell what yourgenes are. BB bb Bb So what is phenotype? Those physical traits that you inherited fromyour parents: Brown hair Blue eyes Red noseoops, sorry! Right handedness Color blindness Straight hairline Create your Smiley face
2 pennies; 1 for each parent; male-female PENNIES ARE MARKED M AND F 1. Flip both coins at the same time for each trait onyour sheet. 2. HEADS= DOMINANT TRAIT TAILS= RECESSIVE TRAIT 3. Circle the capital or lower case letter on yoursheet. 4.Write in the GenotypeCC, cc, Cc
5. Write in the Phenotypeoval face, roundhead. look at the Smiley Face Traits sheet. 6.This will help you create your Smiley facesketch. 7.You will recreate this sketch on yourlaptop in Tech class. Look familiar? Traits are contained in our genes; alsoreferred to as ALLELLES