Traits Lab

DOMINANT/RECESSIVE TRAITS                                 

 (Three hypothesis: Before and after checking traits-class DATA)|  Ind       Class

Hypo 

Ind.

Hypo

Class

ACTUAL

SELF

MOM

DAD

SIB

1

SIB

2

Achoo Syndrome

No Achoo Syndrome

Chin cleft

No cleft chin

Childhood nearsighted

Not nearsighted

Bent little finger

Straight little finger

Dimples

No dimples

Blue eyes

Brown eyes

Attached earlobe

Free earlobe

Left over right thumb

Right over left thumb

Mid-digit hair

No mid-digit hair

Tongue Roller

Non Roller

Freckles

No Freckles

Square/Round  Face

Oval Face(Polygenic Trait)

No tongue flipping

Tongue Flipping

Curly, Wavy, Straight Hair

(Polygenic Trait)

Straight thumb

Hitchhikers thumb

Widows Peak

Straight hair line

Slender eyebrows

Broad eyebrows

Hair on hand

No hair on hand

Shorter big toe than second Toe

Longer big toe than second Toe

Second finger shorter than ring (male)

Second finger longer than ring

(Female)

Second finger shorter than ring

(female)

Second finger longer than ring

(male)

Almond shape eye

Rounded eye

INHERITANCE LAB                                              20 PTS                                                      

NAME__________________________

Traits Lab
PROCEDURE:

1.   As a class, look at the tongue rolling trait.

2.   Record the data for yourself in the table

3.   Collect data for the whole class and determine percentages. (Divide the number of students who have the trait by the students in the class and multiply by 100.)

4.   Collect data from your parents (and siblings), and we will discuss the results of tongue rollers.

DATA:

Dominant phenotype

Recessive Phenotype

Your phenotype

#Students Dominant

#Students recessive

% Dominant

%Resessive

Tongue-roller (T-)

Non-roller (tt)

Dominant phenotype

Recessive Phenotype

# Relatives Dominant

# Relatives recessive

% Dominant

%Resessive

Toungue-roller (T-)

Non-roller (tt)

CONCLUSIONS/ QUESTIONS:

1.   Was your hypothesis correct? Explain.

2.   Does the same percentage of students always display the dominant trait?  Explain.

3.   Why is it possible that the majority can display a recessive trait?

4.   Nationally, about 70% of people are tongue rollers, 30% are non-rollers. Is the class percentage close to the national percentage? Are the class relatives close to the average? Why or why not?