2. Fill in the blanks below using these choices: dominant, genes, genetics, heterozygous, pure, recessive, chromosomes, Punnett square. a. Chromosomes have parts that determine traits. These parts are b. A person having two genes that are alike is said to be C. A gene that prevents others from showing is said to be d. A gene that may not show up even though it is there is said to be e. Long rod-shaped bodies inside a cell's nucleus are called £ One who studies how traits are passed on is studying g.A person with one dominant and one recessive gene for a rait is h. A way to show which genes can combine when an egg and sperm join is a

3. In poultry, a gene C produces creeper (very short legs) in the heterozygous condition and is lethal in the homozygous condition. The c allele of the gene produces normal legs in the homozygous condition. Barring is due to a dominant sex-linked gene, B, and nonbarred to its recessive allele, b. In chickens, males are ZZ (similar to XX) and females are ZW (similar to XY). A creeper male homozygous for barring is mated with a creeper female who is nonbarred. What kinds of offspring can be expected from this cross and in what proportions will each kind occur?

1. In humans, normal pigmentation is due to a dominant gene A. Albinism is due to the recessive allele a. A man without albinism marries an albino woman and their first child is an albino. What are the genotypes of these 3 people? a. Mother:b. Father:c. Child: 2. In humans, achondroplasia “dwarfism” (D) is dominant over normal (d). A homozygous dominant (DD) person dies before the age of one. A heterozygous (Dd) person is dwarfed. A homozygous recessive individual is normal. A heterozygous dwarf man marries a heterozygous dwarf woman… a. What is the probability of having a normal child?b. What is the probability that the next child will also be normal?c. What is the probability of having a child that is a dwarf? Define the following terms:1. Autosome:2. Sex chromosome:3. Carrier:

1. What kind of mutations are most likely to cause genetic diseases? A. Mutations in somatic cells B. Mutations in proto-oncogenes C. Mutations in gamete cells 2. In pea plants, tall height is dominant over short. If two hybrid pea plants were mated, what fraction of their offspring would you expect to be tall? A. 1/4 B. 1/2 C. 3/4 D. 100% all of them

15. Edward was found to be heterozygous (Ss) for the sickle cell trait. Which of the follow ideas regarding Edward's genetic state is incorrect? a. Edward is a carrier of the sickle cell gene b. Edwards' body cells have both copies of the S and s gene. c. ½ of Edward's sperm cells have the S gene and the other half have the s gene d. Edward's parents could have both been carriers themselves e. all of the preceding are correct.

4. An observable, physical trait of an organism is known as a(n) A. Genotype B. Phenotype C. Allele D. Gamete

1.  A man and woman are both affected with the BRCA1 gene for familial breast cancer, a disease that has 80% penetrance in all individuals who carry the allele. They are both heterozygotes for the disease-causing mutation.  What is the probability that they will have a phenotypically normal child?a.  20%b. 40%c. 60%d. 50%e. 80% 2. In populations in Hardy-Weinberg equilibrium, the heterozygote frequency is maximal when the A allele equalsa 0b 0.2c 0.5 d 0.8e 1.0

6.    A heterozygous purple plant is crossed with a white plant. A.    Write the genotype of the purple and white plants. B.    Write the gametes formed by the purple plant and proportions in which they occur.   C.    Write the gametes formed by the white plant and proportions in which they occur.   D.    Combine the gametes using a Punnett square.           E.    Write the genotypes of the offspring and the ratio in which they occur.     F.    Write the phenotypes of the offspring and the ratio in which they occur.       7.    The ability to roll your tongue (R) is dominant to lack of this ability (r). A.    What is the genotype of a man who can roll his tongue if his father couldn’t? B.    If a man who is heterozygous for tongue rolling marries a woman who is heterozygous, what would you predict for the genotypes and phenotypes of their children?                               8.     Huntington’s disease is a degenerative disease of the nervous system that strikes in middle age. The…