Genetics 1 Answers

1) peas have an unusually long generation time.

2) true-breeding.

3) A monohybrid cross involves organisms that are heterozygous for a single character, whereas a dihybrid cross involves organisms that are heterozygous for two characters.

4) dominance.

5) one allele was completely dominant over another.

6) They can be identical or different for any given gene in a somatic cell. They can be dominant or recessive. They can represent alternative forms of a gene.

7) a test cross

8) that the parents were both heterozygous.

9) a dihybrid cross

10) 50%

11) purple-flowered plants and white-flowered plants.

12) predicting the result of genetic crosses between organisms of known genotypes

13) 0

14) 1/64

15) incomplete dominance.

16) 100%

17) roan × roan

18) I-2, II-3, III-1

19) c

20) b

21) a

22) c

23) skin pigmentation in humans

24) environmental factors such as soil pH.

25) 1/4

26) 1/4

27) 1/2.

28) are heterozygous for the sickle-cell allele. are usually healthy. have increased resistance to malaria. produce normal and abnormal hemoglobin.

29) many factors, both genetic and environmental, contribute to the disease.

30) epistasis

31) e

32) b .

33) a

34) c

35) d

36) amniocentesis chorionic villus sampling

37) incompletely dominant

38. the random arrangement of chromosomal tetrads at metaphase I

39.. dominant

40. AA

41. 50

42. 100%

43. 8/16

44. Traits are inherited in discrete units, one from each parent.

45. is all its traits actually expressed

46. 3/4

47. Cc

48. 190

49. F2 generation of a dihybrid cross

50. intermediate inheritance

51. red x white

52. It cannot be done.

53. 2

54. mitochondrial DNA and X chromosome