2 QuestionA cross between two pea plants hybird for a single trait produces 60 offspring. Approximately how many of the offspring would be expected to exhibit the recessive trait?
3 Answer Pp x Pp ¼ pp = recessive trait Answer: 60 offspring x ¼ = 15 offspring would express the recessive trait
4 QuestionCompare the final products of mitosis to the final products of meiosis.
5 AnswerMitosis:2 diploid (2n) daughter cells that are identical to the original cellMeiosis:4 haploid (n) gametes (sperm or eggs)
6 QuestionDetermine the possible genotypes & phenotypes of the children for a couple who's blood types are homozygous A & heterozygous B.
7 Answer50% (2 of 4 squares) are IAIB & those kids would have AB blood. The other 50% (2 of 4 squares) are IAi, those kids will have Type A blood.
8 QuestionExplain the difference between diploid and haploid.
9 AnswerDiploid= The state of having each chromosome in two copies per nucleus or cell.Haploid= The state of having one copy of each chromosome per nucleus or cell.
10 QuestionIn hamsters, black coat is dominant to white coat and rough coat is dominant to smooth coat. If two heterozygous black-rough coated hamsters where mated. What would be the phenotype ratio of the F1 generation?
12 QuestionExplain the difference between homologous chromosomes and sister chromatids.
13 AnswerHomologous Chromosomes= A pair of chromosomes made up of two homologs. Homologous chromosomes have corresponding DNA sequences and come from separate parents; one homolog comes from the mother and the other comes from the father. Homologous chromosomes line up and synapse during meiosis.Sister Chromatids= 2 duplicates of a chromosome created by replication.
14 QuestionIn cats, the allele for black fur is dominant to the allele for brown fur, and the allele for short hair is dominant to the allele for long hair.Homozygous black fur heterozygous short hair male, heterozygous black fur long hair femaleGive Genotype and Phenotype Ratio
15 Answer BBSs x Bbss Genotype ratio = 4 BBSs : 4 BBss : 4 BbSs : 4 Bbss Phenotype ratio = 8 Black-short : 8 Black-long
16 QuestionIn human cells, 2N=46. How many chromosomes would you expect to find in a sperm cell? In an egg cell? In a cell in your brain? Explain your answers.
18 QuestionIf a man with hemophilia (difficulties with blood clotting) marries a homozygous normal woman, what is the probability of them having a hemophiliac child?
19 AnswerSince the mom is not a carrier there is a 0% chance of having a hemophiliac child
20 Question- 2 part What is crossing over and when does it occur? Which part of meiosis is most like mitosis?
21 AnswerCrossing Over= The exchange of DNA sequences between chromatids of homologous chromosomes during meiosis, occurs in prophase 1.Meiosis 2
22 QuestionA test was done to determine the biological father of a child. The child's blood Type is A and the mother's is B. Dude #1 has a blood type of O, & dude #2 has blood type AB. Which dude is the biological father?
23 AnswerIt is possible with the mom and Dude #2 to produce the child
24 QuestionIn tomato plants, the allele for purple stems is dominant to allele for green stems and the allele for red fruit is dominant to the allele for yellow fruit. If two tomato plants heterozygous for both traits are crossed. state what proportion of the offspring would be expected to have purple stems and yellow fruit.
30 QuestionIn garden peas, tall vine (T) is dominant and short vine (t) is recessive. If a heterozygous tall pea plant is crossed with a short pea plant, what genotypes and phenotypes are possible in the F1 generation?
31 Answer Heterozygous tall pea plant = Tt Short pea plant = tt Answer: Genotypes for F1 = Tt and ttPhenotype for F1 = Tall and short
32 QuestionGive the genotypic and phenotypic ratio of the potential children of a couple, if the man is heterozygous A-type blood and his wife is heterozygous B-type blood.
33 Answer Genotype ratio = 1 IAIB : 1 IBi : 1 IAi : 1 ii Phenotype ratio = 1 AB : 1 B : 1 A : 1 O
34 QuestionWhat are the possible blood types of a child who's parents are both heterozygous for "B" blood type?
35 AnswerThere is a 75% (3 of 4) chance that the child will be Type B, and a 25% (1 of 4) chance that the child will inherit Type O (ii).
36 QuestionIn dogs, wirehair is a dominant trait, smooth hair is recessive. Two wire-haired dogs produce a male puppy that is wire-haired. To find out most quickly whether he carries the allele for smooth hair, he should be mated to a specific type of female. What is the name of this senario? (be specific for the term)
37 AnswerHe should be mated with a smooth haired (homozygous recessive), this would be a test cross
38 QuestionIn garden peas, axial flower position is dominant and terminal flower position is recessive; tall vine is dominant and short vine recessive. A plant known to be purebred for tall vine and axial flowers is crossed with a plant having short vines and bearing terminal flowers. What is the genotype of the offspring?
40 QuestionIn cocker spaniels, black is a dominant trait (B), red is recessive (b). Solid color is dominant (S) and white spotting is recessive (s). A red male was mated to a black-and-white female. They had five puppies as follows: 1 black, 1 red, 1 black-and-white, and 2 red-and-white. What are the genotypes of the parents?
41 Answer Male = bbS? Female = B?ss * need to look at puppies to determine genotypesSince all phenotypes appeared, then the parents must have been heterozygous for the traitsAnswer: Male = bbSsFemale = Bbss
42 QuestionWhat are the chances of a woman with Type AB and a man with Type A having a child with Type O?
44 QuestionOptic atrophy (blindness due to degeneration of the optic nerve) occurs as a result of the action of an X-linked recessive gene. A woman with the optic atrophy marries a normal man. What is the expected genotypic and phenotypic ratio of their children?
45 Answer Woman=XaXa woman with optic atrophy Man= XAY normal man Genotypic Ratio: 2XAXa:2XaYPhenotypic Ratio: 2 female carriers: 2 males with optic atrophy
46 QuestionIn cattle, hair color shows codominance. Red is dominant, and white is recessive. In the heterozygous condition codominance is shown as roan (something of a light red) coat color. If a roan bull and a roan cow are mated over several years and produce 12 offspring. How many of the offspring would be expected to be white? Roan?
48 QuestionIn flies, white eyes are an X-linked recessive trait. Cross a carrier female with a red-eyed male fly. What % of the children would have white eyes? What % of the girls would be carriers? What percent of all the kids would be carriers?
49 Answer Female=XRXr Male=XRY 25% white eyed offspring 50% of girls would be carriers25% of all kids would be carriers
50 Question Polyploid organisms results from: (a) crossing over (b) non disjunction(c) mitosis(d) random assortment