Gene, DNA & Chromosome
Analyzing Punnett Squares
Alleles
Dominant & Recessive
Random
200
How many chromosomes do humans generally have?
46
200
What are the genotypes of the parents? 
BB & Bb
200
Is this a dominant or recessive allele? G
Dominant
200
What is the dominant phenotype?
Brown Eyes
200
Give me a heterozygous genotype using the letter G
Gg
400
What is structure C?
A Gene
400
What percentage of the offspring will have the dominant phenotype? 
100%
400
Is this a dominant or a recessive allele: d?
Recessive
400
A botanist crosses a pea plant that produces smooth seeds and wrinkled seeds. All of the offspring are smooth. What is the dominant trait, and why?
Smooth seeds are dominant.
400
If you are a "carrier" for a trait, what is your genotype?
Heterozygous
600
What is the name of structure A?
Chromosome
600
What percent of the offspring will be homozygous? 
50%
600
What is the recessive allele? 
y
600
What is the dominant phenotype?
Blue Flowers
600
What percentage of the offspring will have the dominant trait? 
75%
800
What is structure B&C combined?
DNA
800
What percentage of the offspring will carry a recessive gene?
50%
800
What is the dominant allele?
A
800
A scientist crosses a white plant and a purple plant. What might happen that would make the scientist think that the purple plants are dominant?
If all of the offspring were purple.
800
Two insects produce 500 offspring. EVERY SINGLE ONE has the genotype Hh for a trait. What are the likely genotypes of the parents?
HH and hh
1000
What is the difference between DNA and a gene?
Genes control ONE trait, and DNA is all of the genes that control ALL traits.
1000
What are the alleles of the parents? 
Dd & dd
1000
If you have two recessive alleles for eye color, what color eyes will you have?
Blue/Light
1000
The shaded individuals represent one phenotype, while the unshaded individuals represent another. Which do you feel represents a dominant trait, the shaded or unshaded allele? 
The unshaded allele is dominant.
1000
Why will their offspring ALWAYS have the dominant trait? 
Because the mother can ONLY pass a dominant gene.