Human Trait Activity

Baby Face Activity Name______per ___ Introduction: When practice using Punnett squares, teachers often give problems involving plants or small mammals. Instead, in this lesson, you will be finding out about some of your own traits. For this exercise, all dominant traits will be heterozygous. This will make the results a little more interesting, and will save time and paper. Define Heterozygous – Phenotype Homozygous = Genotype Dominant trait - Recessive trait - After the you determine your traits and their genes, you will 'mate' with a partner. For each trait, partners will set up and complete a Punnett square and determine the phenotypic ratio of the offspring. Finally you make an illustration of the offspring. If help is needed in determining what the traits look like, refer to a Create-A-Baby-Lab on the internet.

Objectives: Materials: 1. To practice Punnett squares. 1. Partner ('Mate') 2. To investigate genetic traits. 2. Pens or pencils

Procedure: 1. Check off which traits you have in Table 1. 2. Determine and record your gene make up in Table 2. 3. Mark off your partner's traits in Table 1. If you don’t have a partner, use the teacher’s traits. 4. Determine your partner's genetic make up in Table 2. 5. Using the information in Table 2, set up and complete a Punnett square for each of the traits. 6. Determine the phenotypic ratio for each trait.

Results: Table 1: Phenotypes Your phenotype and your partner's phenotype. (Remember: a dominant trait is automatically heterozygous for this activity.) Dominant Traits Recessive Traits You Partner Trait You Partner Trait Straight hair Curly hair (Hh) (hh) Widows' Straight Peak Hairline (Ww) (ww) Free Ear Attached Ear Lobes (Ee) Lobes (ee) Freckles (Ff) No freckles (ff)

Right Left Handed Handed (Rr) (rr) Straight Hitch-hikers thumb (Ss) thumb (ss) Tongue Non-tongue Roller (Tt) Roller (tt) Table 2: Gene Make Up Record genotypes in Table 2. Trait Your genotype Partner's genotype Hair Hair line Ear lobes Freckles Hand Preference Thumb Tongue

Punnett Squares: Hair Phenotypic Ratio:__%_____:__%_____

Hair line Phenotypic Ratio:__%_____:__%_____

Ear lobes Phenotypic Ratio:__%_____:__%_____

Freckles Phenotypic Ratio:__%_____:__%_____

Hand Preference Phenotypic Ratio:__%_____:__%_____

Thumb Phenotypic Ratio:__%_____:__%_____

Tongue Phenotypic Ratio:__%_____:__%_____

On the back of this sheet, make an illustration of your offspring and complete the conclusion questions! Conclusions:

Define the following terms:

chromosome-

allele-

locus-

codominance-

incomplete dominance -

1) How many genes does it usually take to code for a trait?

2) How many genes do the parents usually give for each Dominant/Recessive trait?

3) What percentage of the genotype does each parent give to the offspring?

4) What happens to the alleles for incomplete dominance trait?

5) Which gene is expressed for an incomplete dominance trait?

6) What happens to the alleles for a codominant trait?

7) Which gene is expressed for a codominant trait?

Congratulations!!