Unit Test Study Guide
7th Grade PSI Science
Name ___________________________________
Use the chart to answer questions 1-5:
A B represents large lips and b represents smaller lips.
Father
Mother
Bb
BB
1) What trait can only be inherited from the father? ___________________________________
2) What is the phenotype for the father? ____________________________________________
3) What is the phenotype for the mother? ___________________________________________
4) Set up and complete the monohybrid cross in the space below:
5) What is the probability (as a percentage) of offspring that will have big lips? _______________
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7th Grade PSI
Inheritance and Variation of Traits
6) The process in which DNA is duplicated in the cell prior to the cell dividing is called
____________________________________.
7) The process in which the sex cell divides and splits the DNA in half is called _________________.
8) Name three differences between sexual reproduction and asexual reproduction:
a.
b.
c.
9) Which type of reproduction would create offspring that look more similar to the parent?
a) SEXUAL
b) ASEXUAL
10) One parent has blue eyes (genotype: bb). The other parent has brown eyes (genotype:
unknown). They have 6 children and 1 of these children has blue eyes. What must be the
genotype of the brown-eyed parent?
________________________
Why?
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
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7th Grade PSI
Inheritance and Variation of Traits
For questions 11-12, corn plants can either have normal height (N) or short height (n).
11) Which trait is dominant? _____________________________________________
12) Use this information to complete each of the crosses below:
a. Homozygous dominant x Homozygous recessive:
b. Homozygous dominant x Heterozygous:
c. Heterozygous x Heterozygous:
d. Homozygous recessive x Heterozygous:
e. In a-d, shade the homozygous dominant offspring red - heterozygous offspring are
green - homozygous recessive offspring leave white.
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7th Grade PSI
Inheritance and Variation of Traits