Genetics Study guide
1.
Genes that come in slightly different molecular forms are called _______________
2.
Analysis of these observable traits all started with a monk named _____________________ and
some peas growing in his monastery garden.
3.
What plant did Mendel use in his experiments? _____________________
4.
What is meant by true-breeding? _____________________
For the following If Tall peas (T) are dominant over dwarf peas (t) write the two alleles to show
5.
Homozygous dominant _____________________
6.
homozygous recessive _____________________
7.
heterozygous
8.
What is a gene?
9.
What is a locus? _____________________
_____________________
10. What is an allele?
11. Each Parent donates how many alleles for every gene? _____________
12. What are homozygous alleles? _____________________
13. What are heterozygous alleles? _____________________
14. Genes influence the development of ___________________________.
15. Define genotype and give examples: _____________________
16. Define phenotype and give examples: _____________________
17. Dominant alleles are represented by ___________________;recessive alleles by ___________
18. Both homozygous dominant and heterozygous gentotypes yield a ____________________ phenotype.
19. What are monohybrid crosses?
20. What does P1 mean in a monohybrid cross
21. Explain what Mendel found in the F1 and P1 generations
22. What is a Punnett square?
23. The Mendelian theory of segregation states that diploid organisms inherit _______ genes per trait,
and each gene segregates from the other during meiosis such that each gamete will receive only
______ gene per trait. He called this the Law of ________________________
24. What is a Testcross ?
25. What is the law of Dominance?
26. What is the law of Independent Assortment?
27. What are crosses involving two traits such as Tall, Green peas crossed with yellow short peas called?
28. What is the Phenotypic Ratio for di-Hybrid crosses with 2 heterozygotes?
29. We now know that genes located on _____________ chromosomes segregate independently of each
other and give the same phenotypic ratio as Mendel observed: 9:3:3:1.
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Genetics Study guide
30. The Mendelian theory of ___________ assortment states that each gene of a pair tends to assort into
gametes independently of other gene pairs located on nonhomologous chromosomes.
31. What is the difference between complete dominance, incomplete dominance, and codominance.
32. Define multiple alleles and give an example __________________________________________
33. What is incomplete dominance?
34. You cross a red flower, a white flower and get a pink flower. Create a punnett square to show this.
35. When both alleles are equally expressed such as Black and White dogs breed to get a black/white
puppy, then this is called __________________________
36. Blood type is determined by markers produced by three genes—a ________ ________ system.
37. IA and IB are each dominant to i, but are ______________ to each other.
38. What are the possible alleles for the following blood types?
39. Type A _______ & _______ Type B ____ & ________
40. Type AB ______ Type O ____________
41. What is pleiotropy
42. Explain why sickle-cell anemia is a good example of pleiotropy?
43. ._________ is a condition in which one gene pair masks the expression of another gene. Albinism is
an example
44. The black, brown, or yellow fur color in Labrador retrievers is the result of variations in the amount and
distribution of the pigment __________.
45. The alleles of one gene control the _____________ of melanin (black and brown) while another
specifies its deposition (less of the pigment results in the yellow color).
46. What is epistasis, and give an example
47. Describe a carrier.
48. What two sex chromosomes does a male have?
49. What sex chromosome does a female donate in each egg?
50. What is the probability of a human offspring being female?
51. Define X chromosome inactivation.
52. What chromosome are most sex-linked genes located on?
53. Gene expression, such as the sex in sea turtles, can be influenced by what?
54. What can easily be identified with a karyotype?
55. In a pedigree, what does a circle represent?
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