Download genetics test study guide

GENETICS TEST STUDY GUIDE
NAME:__________________________
DATE:_____________
BLOCK:______
1. Tongue rolling (R) is dominant over non-tongue rolling (r). If a person cannot roll their tongue, what
would be his/her genotype? _____
2. Genetic disorders like Down syndrome are caused by __________________.
3. What is the process of cloning? ________________________________________________________
4. The failure of one or more pairs of chromosomes to separate is called _____________________.
Round seed pods are dominant over wrinkled seed pods. The Punnett square below shows a cross
between parents with round and wrinkled seed pods. Use the following diagram to answer the next
three questions.
5. What is the phenotype of the offspring in block A? ________________
6. What is the genotype of the offspring in blocks B and D? _____________
7. What is the phenotype of the offspring in block C? ________________
8. In 1910, Thomas Morgan discovered traits linked to sex chromosomes in fruit fly. The Punnett square
below shows the cross between red-eyed females and white-eyed males. Fruit flies usually have red
eyes. If a female and male offspring from the cross shown below are allowed to mate, list what the
offspring would probably look like? (see figure)
__________________________________________________________________________________
9. Which genotype illustrates codominance of alleles that control blood type in humans?_________
10. What conclusion about the F1 genotype can be drawn from the genetic information
above?____________________________________________
11. In pea plants, purple flowers are dominant to white flowers. If two heterozygous purple plants are
crossed, what percent of the offspring will probably be white? ________
12. Examination of the diagram indicates that these are the chromosomes of a __________ with ________
______________.
13. In cats, gene E produces yellow fur and gene B produces black fur. A cat that inherits both of these
genes has patches of yellow and black fur and is known as a calico. The alleles for black or yellow are
located on the X-chromosome. Calico coat color is most likely due to ________________ _______________ genes.
14. Complete the Punnett square below for a cross of cats.
15. What is the phenotype of the male cat? _______________
16. What is the phenotype of the female cat? _______________
17. List what the offspring look like. ________________________________________________________
18. One way to increase the number of organisms in an endangered species is to let the few remaining
individuals of that species breed. However, this breeding may also lead to species extinction because
inbreeding over a short period of time may reduce ___________ _______________.
19. In cows, long hair is dominant to short hair. In a cow that is heterozygous for long hair, what percentage
of the cells undergoing meiosis will carry the dominant allele? ___________.
20. Forms of the same gene with different phenotypic expressions are called ____________.
21. In corn plants, green (G) is dominant to albino (g). What is the chance of a heterozygous cross
producing albino corn plants? ____________
22. What do eye color, skin color, and blood group have in common?______________________________
23. When using Punnett squares to show inherited probability, a capital letter stands for the
________________ allele.
24. In humans, a disease inherited by a single pair codominant genes is _______________ ___________.
Using the genetic pedigree above, answer the following questions.
25. Person #4 represents _______________________________________.
26. Person #3 represents a _____________________________________.
27. Person #1 had to be _______________________.
28. In turkeys, the dominant gene B results in black pigment throughout the feathers. Most of the feathers
of homozygous recessive individuals have light edges. Heterozygous individuals have a few feathers
with light edges. If two turkeys with mostly light-edged feathers are crossed, how many chicks would
probably have only the black-pigmented feathers? _______________________
29. In a Mendelian Cross of purebred dominant and purebred recessive, the ratio of dominant to recessive
in the F1 generation is __________.
30. A color-blind woman marries a man who has normal color vision. What are their chances of having a
color-blind daughter? ____________
31. A genetic pedigree showing that only males are affected by a certain disorder is evidence of what type
of inheritance? _____________
32. In mice, the gray fur gene (G) is dominant and the gene for black fur (g) is recessive. If 50% of a mouse
litter is black, what parental cross probably produced this result? _____X_____
33. If a man has type O blood, his red blood cells would have what type of antigen? ___________
34. If “S” stands for a dominant form of the “smooth” gene in a plant (producing smooth leaves), and “s”
stands for a recessive form of the “smooth” gene (producing wrinkled leaves), what gene structure
would a hybrid plant have? ______
35. Two hybrid fruit flies each have one dominant gene for brown eyes (B) and one recessive gene for red
eyes (b). They are mated. What percent of the offspring have brown eyes? ________
36. Mendel’s early work with pea plants demonstrated a significant genetic discovery. The crossing of
homozygous tall pea plants with homozygous short pea plants always resulted in tall plants and
demonstrated that tallness in pea plants is a trait that is _______________.
37. In parrots, a sharp beak (A) is dominant to a dull beak (a), and shiny feathers (L) are dominant to dull
feathers (l). According to this Punnett square, how many of the baby parrots from this cross could have
a dull beak and dull feathers? ___________________ Circle the appropriate boxes.
38. What is the chance that the child of two individuals, one heterozygous with Type A blood, and the other
heterozygous with Type B blood, will have Type O blood? _______________
39. An allele that expresses itself in a hybrid is a(n) ________________.
40. An organism in which two alleles for a trait are different is _________________.
41. Each of the seven pea traits that Mendel studied occurred in ___ ___________, _____________ forms.
42. When purebred tall plants are crossed with hybrid tall plants, the offspring would be
_______________________________________________________________________________
43. Another name for clones could be _______________ __________. (HINT: natural clones)
44. Crossing a pure-bred green pod plant with a purebred yellow pod plant is symbolized by ____ X ____
45. Traits that are found on the X chromosome are said to be _____-___________.
46. A person has been diagnosed with AIDS. Did this is this the result of a genetic mutation? ______
47. The actual genetic makeup of an organism is called its _________________.
48. What an organism looks like is referred to as its _______________.
49. In a Mendel’s experiment, the monohybrid cross of the short and tall plants in the Pl generation resulted
in 100 % heterozygous plants in the Fl generation. What was the phenotypic ratio of the F2
generation?_________________________
50. In the figure, what disorder does the person have with chromosome pattern number 4?
___________________________
51. Complete the Punnett Squares below and answer the following questions.
In Hobbits, hairy feet are dominant over hairless feet.
F1 generation: cross 1
homozygous dominant
with a homozygous
recessive
F2 generation: cross 2
of the offspring of the
F1 generation
52. In the first generation, what portion of the Hobbits has hairless feet? ___________
53. In the first generation, what portion of the Hobbits has hairy feet? ___________
54. In the second generation, what portion of the Hobbits is purebred? ____________
55. In the second generation, what portion of the Hobbits has hairless feet? ____________
56. What are the genotypes that you would have to cross to get Hobbit offspring with 50% hairy feet and
50% hairless feet? _______ X ______