Dominant Recessive Allele Quiz

We can figure our the possible allele combinations of offspring by using a Punnett Square

Mendel then started testing other traits in the pea plants

Lets do some practice Punnett Squares using these traits!

What if we want to do a Punnett Square for more than one trait?

-We can do what is called a dihybrid cross. A cross between two traits

Lets practice!

Lets take a look at crossing over and genetic recombination

What will your children look like?

Class Activity

Get into pairs and use this chart of mendelian traits to figure out what your children will look like

In some cases you will have to create a Punnett Square and tell me the probability of your offspring having the trait. If you are not sure if you are homozygous dominant or heterozygous for a trait make a guess based on the traits your parents have. (15pts)

Mendelian Traits in Humans

Dominant Recessive

Hazel or green eyes Blue or grey eyes

Freckles No freckles

Dimples No dimples

Normal chin Receding chin

Broad nose Narrow nose

White hair streak Normal hair coloring

Kinky hair All other hair types

Abundant body hair Little body hair

Nearsightedness Normal vision

Astigmatism Normal vision

Mongolian Fold No fold in eyes

Broad lips Thin lips

Large eyes Small eyes

Short stature Tall stature

High blood pressure Normal blood pressure

Six fingers five fingers

Webbed fingers Normal fingers

Dwarfism Normal growth

Migraine No Migraine

A blood type O

B blood type O

Rh factor (+) No factor (Rh -)

Free earlobes Attached earlobes

Baldness (male) Not bald

Roll tongue Cannot roll tongue

Second toe longest First (big) toe longest

Tone deafness Normal tone hearing

Left thumb cross Right thumb cross

Right handed Left handed

Taste PTC Not taste PTC

Sodium Benzoate No Sodium Benzoate

Thiourea Not taste Thiourea

Dark Hair Light Hair

Widows Peak No Widows Peak

Bushy Eyebrows Fine Eyebrows

Long eyelashes Short eyelashes

Mid-digit Hair No hair on mid-digit

Bent little finger Straight little finger

Foot arch low arch

Hitch-hiker thumb No hitch-hiker thumb

After you are done draw your child! (5pts)