Genetics Final Review 2014

Name______Sci _____

  1. What is theprocess that eliminates creatures with inferior traits and preserves those with superior traits?
  1. In a certain monster species,the 3- Eye phenotype is controlled by the dominant allele, “T”. Homozygous recessive creatures have only one eye. What phenotypes result from a hybrid x hybrid mating? Fill out the punnett square below and draw the children:
  1. What percentage of the possible kids in the Punnett Square above will show the dominant trait? ______%
  1. When does segregation occur? ______
  2. Mendel's principle of independent assortment says: ______
  3. Explain the relationship(s) among the following: DNA, alleles, genes and chromosomes.
  1. How does the Tay Sachs allele (n) survive in a population if all affected people with the disease die before they can reproduce? Breed 2 carriers to find out. Tay Sachs = nn.
  1. What is the result of mitosis and meiosis?

Mitosis results in: / Meiosis results in:
  1. Briefly explain the genetic cause and symptoms for each genetic disorder:

Hemophilia / Down's Syndrome
Klinefelters / Cystic Fibrosis
  1. What are the phases of mitosis and meiosis in order? You may use single letters to represent each stage (I = interphase).

Mitosis: / Meiosis?
  1. What causes variation in a population? ______
  2. How many different gametes will these genotypes make? (AA, Bb, Cc) (QQ, rr, SS) (Xx,Yy, zZ)
  1. Creature (Bb, ee) mates with (bb, eE). Segregate each gene. Write the gametes on the top and on the side of the squares. Draw the kids in each square! Draw a round head for each child.
  1. Recessive sex-linked conditions like hemophilia and colorblindness are most common in boys because….
  1. Hemophilia is represented by “n”. A normal, healthy allele = “N”. A female carrier of hemophilia (XNXn) marries a healthy male (XN Y). Draw a punnett square and predict their kids.
  1. ______% What percentage of the offspring in the problem above will have hemophilia?
  1. Who is responsible for producing sons with hemophilia? MOMDAD
  1. Let “N” represent a normal allele and “n” represent an abnormal allele. A shaded shape represents a person who has a genetic disease. Square = male, circle = female. (Autosomal chromosomes are not sex chromosomes.) Look at the pedigree below. Write the genotype of each parent to find out. Is the following recessive disease sex-linked or autosomal? Choose A or B.

/ A) This pedigree shows a sex-linked recessive disease and the daughter is “Xn Xn”.
B) This pedigree shows an autosomal recessive disease and the daughter is “nn”.
  1. The following pedigree shows a recessive, sex-linked disease. The affected son has the following genotype: XnY. What are the genotypes of both parents?
  1. Population Genetics: The frequency of the sickle cell allele (n) in a population is 0.3. What percent of the population will be carriers?

N = / n = 0.3
N
n
  1. What ratios result from a dihybrid x dihybrid mating? (Aa, Bb) x (Aa, Bb)