Name _____________________________________________
Date ____________
Period _________
Genetics Review Sheet
Fill in the following paragraph with the correct term or definition. If a term is required there is a (t) beside
the blank. If a definition is required there is a (d) beside the blank. If a number is required there is a (#)
beside the blank.
Gregor 1. (t)______________ is known as the father of genetics. Genetics is the 2. (d) ________________
_________________ which means 3. (d) _________________________________________________.
The idea of heredity involves physical characteristics called 4. (t) _____________ or 5. (t) _____________.
From Mendel’s pea experiments he concluded that there are at least two forms of each trait called 6. (t)
____________________. During the process of meiosis, sex cells called 7. (t) ________________ are
formed. The two types of sex cells are 8. (t)_____________ and 9. (t)_______________ and each sex cell
contains one allele. When the two sex cells unite in a process called 10. (t)_______________________, the
zygote now has 11. (#)_________ alleles for each trait. The phenotype or the 12. (d)_________________
____________________________ of the offspring are determined by the genotype. If the genotype of the
offspring has the same alleles, the offspring is said to be 13. (t)___________________________ and if the
genotype of the offspring has different alleles, the offspring is said to be 14. (t) _______________________.
15. Polydactylism is a condition where a person has an extra finger or toe. It is caused by a dominant gene (P).
A polydactyl whose father was normal marries a normal woman. Is it possible for this couple to have
normal children? If so, what is the percentage?
16. Green seeds are dominant to yellow seeds and smooth seeds are dominant to wrinkled seeds in pea
plants. If two heterozygote green and smooth pea plants are crossed, what are the possible phenotypes
and ratio of the offspring?
17. In a cross between two white mice, in several litters 49 of the 205 offspring were black. What color is
dominant? What are the genotypes of the parents and the black offspring?
___________ Male parent ________ Female parent __________ black offspring
18. In Andalusian fowl, the allele for black plumage B is incompletely dominant to the allele for white plumage
B’. The heterozygote genotype BB’ results in grey plumage. What is the genotypic and phenotypic ratio of
the following crosses.
A. black and grey
B. grey and grey
A. Shroufe
Biology 04-05
Name _____________________________________________
Date ____________
Period _________
19. What is the probable genotypic ratio among children born to a mother with type O blood and a father
with type AB blood? A mother with Type A and father with type B?
20. Red (R) is codominant with orange (O) in cloned sheep. If a red-orange male is crossed with an orange
female what is the phenotypic and genotypic ratios.
21. In humans, the genes for colorblindness and hemophilia are both located on the X chromosome with no
corresponding gene on the Y. These are both recessive genes. If a man and a woman, both with normal
vision, marry and have a colorblind son, draw the Punnett square that illustrates this. If the man dies and
the woman remarries to a colorblind man, draw a Punnett square showing the type(s) of children that
could be expected from this marriage. How many/what percentage of each could be expected?
22. Describe in words the relationship of the individuals in the following pedigree. The people in this pedigree
that are marked as affected have a cleft chin. Give the genotypes of person number 1, 2, and 3.
23. Give two examples of polygenic traits in humans and explain why they are polygenic.
24. Give two examples of environmental influence and explain the difference between external and internal
influences.
25. What is a karyotype and why are they useful?
**Also…study all handouts, notes, problems, and materials in your portfolio!
A. Shroufe
Biology 04-05