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Population Genetics: Genetic Frequency

1. In ladybugs, wings with 4 spots are recessive to those with 2. Assume 11% of the ladybugs have 4 spot wings. If the mutation rate of 2 spot to 4 spot alleles is 0.047, what percentage of the next generation will be heterozygous? 2. You look at two populations of moose, one from Canada, and one from Newfoundland, an islan

Population Genetics

3. In plants, flower color is controlled by incomplete dominance, where red and blue are the two homozygous conditions and purple indicates heterozygous. An initial population contains 14 red, 70 purple, and 24 blue individuals. Give exact allele and expected genotype frequencies for this population. Now assume that the heter

Genetic Material

All living organisms contain genetic information that provides several functions inherent to the individual organism and the perpetuation of its species. a) Describe how genetic material contributes to the regulation of physiological function and development b) Discuss how the nature of genetic material both perpetuates

MONOHYBRID CROSS for brown eyes and blue eyes in humans

In humans, brown eyes (B) are dominant over blue (b)*. A brown-eyed man marries a blue-eyed woman and they have three children, two of whom are brown-eyed and one of whom is blue-eyed. Draw the Punnett square that illustrates this marriage. What is the man's genotype? What are the genotypes of the children? (* Ac

Meiosis for someone who is heterozygous for two genes.

There is a gene R on the long arm of the same chromosome as the huntington gene. (1) Draw a labelled diagram to show the chromatids of a diploid cell at the end of anaphase 1 of meiosis, for a person who is heterozygous for both characters. (2) Draw a labelled diagram to show the product cells derived from this cell at tel


How would a pair of sister chromosomes differ from homologous chromosomes? If the reproductive cell only has 23 chromosomes, then how come all of our body cells (somatic cells) have 46 chromosomes? Briefly describe the constituent molecules found within a chromosome. You may use a diagram to illustrate your answer. Refer

Determining probability of inheriting disease gene

Part I: Imagine you have a friend who is getting married and plans on starting a family right away. She asks your advice about preconception genetic screening because she is concerned about the chance that her future children could have cystic fibrosis. Her fiancé has a sister that has cystic fibrosis, and she has a cousin wh

Gamete distribution and offsprings from select matings

1) Consider a genetic locus that could hold either of the alleles P or p (where P is dominant, p is recessive). Consider a second genetic locus (for some other unrelated trait) that could hold either of the alleles R or r. Listed below are some genotypes of individuals for each of these loci: a) PPRR b) PpRR


2. The inbred mouse strains BALB/c and C57BL have different Ig heavy chain allotypes: The BALB/c allele is IgHa, whereas the C57BL allele is IgHb. C57BL mice make good immune responses to the antigen "Z", but BALB/c mice respond poorly. Assume you produced (BALB/c X C57Bl)F1 mice, then back-crossed these F1s to BALB/c. You te

What can you conclude about the gene(s) encoding VH and CH?

Recall that allelic forms of Ig constant regions exist. In the mouse, the locus encoding Ig heavy chain constant regions is named IgH. The inbred mouse strains BALB/c and C57BL/6 have different IgH alleles: BALB/c mice are IgHa and C57BL/6 mice are IgHb. They also differ in their humoral response to phosphorylcholine (PC). While

Which Cell is the Cancer Cell?

Herbie is a typical American college freshman who loves to eat. His second most favorite food is hotdogs. He cuts them into his Kraft macaroni and cheese at a 1:1 ratio, going through a score of hotdogs each week. He doesn't know his brand is preserved with sodium nitrite, but his stomach is slowly finding out as it's acid conve

Modification of Mendelian Rations

In pings, coat color may be sandy, red, or white. A geneticist spent several years mating true-breeding pigs of all different color combinations, even going so far as to obtain true-breeding lines from different parts of the country. For crosses 1 and 4 below, she encountered a major problem: her computer crashed and she lost


A. What is your evidence that DNA is the genetic molecule of heredity? b. The Human Genome Project began with two goals: to know the sequence of genes on all the human chromosomes and to know the sequence of bases on all the human chromosomes. With this, individuals with genetic defects could have proper treatment. Pre

Biology questions about RNA, mitosis, and definitions of genetics terms

1. What are the three types of RNA? What is the function of each? 2. Define mitosis and cytokinesis. What would a daughter cell look like if cytokinesis did not occur after mitosis? 3. Define the following terms: gene, allele, dominant, recessive, true breeding, homozygous, heterozygous, cross-fertilization, self-fertiliza

Mode of inheritance

Labrador retrievers may be black, brown, or golden in color. While each color may breed true, many different outcomes occur if numerous litters are examined from a variety of matings, where the parents are not necessarily true-breeding. The results below show some of the possibilities. Propose a mode of inheritance that consiste

Expected offspings from block and tortoiseshell female

In cats, yellow coat color is determined by the b allele, and black coat color is determined by the B allele. The heterozygous condition results in a coat pattern known as tortoiseshell. These genes are x-linked. What kinds of offspring would be expected from a cross of black male and a tortoiseshell female? What are the chances

Inheritance pattern problems

Given the inheritance pattern of the coat color in rats described in the previous problem, predict the genotype and phenotype of the parents that produced the following F1 offspring: (a) 9/16 gray:3/16 yellow:3/16 black:1/16 cream; (b) 9/16 gray:3/16 yellow:4/16 albino; (c) 27/64 gray:16/64 albino:9/64 yellow:9/64 black:3/64 cre

Colorblindness is explained.

Since colorblindness is a sex-linked recessive trait: A) fathers of all colorblind sons must be colorblind B) fathers of all colorblind daughters must be colorblind C) mothers of all colorblind daughters must be colorblind D) mothers of all colorblind sons must be colorblind E) all the sons of carrier female

Segregation and allelic frequency problem

Perhaps you are a fan of the PowerBall Lottery Game. We often have our favorite numbers and daydream about how we would spend our winnings. You may be glad to know that you have already won a lottery - when you were conceived. You have some characteristics of both parents - but also characteristics which seem to be uniquely y

Genetics Problem - Color Blindness

Colorblindness in humans is x-linked recessive trait. Question: One out of every 12 human males has red green colorblindness. How common is it among human females. Can you show me how to determine its prevalence among females as a genetics problem? I believe the answer to this problem is 1/200 females are colorblind. I

Can you determine the genotypes of the parents of this cross? Determine the genotypes of the three dogs. Explain why the F1 are all red and how the 9:6:1 ratio of the phenotypes in the F2 occurred.

1.) Fur color in rabbits is determined by a single gene locus for which there are four alleles. Four phenotypes are possible: black, Chinchilla (gray color causes by white hairs with black tips), Himalayan (white with black patches on extremities), and white. The black allele (C) is dominant over all other alleles, the Chinchil

Mendel and the Gene Idea

1.) In dogs, black (B) is dominant to chestnuts (b), and solid color (S) is dominant to spotted (s). What are the genotypes of the of the parents that would produce a cross with 3/8 black solid, 3/8 black spotted, 1/8 chestnut solid, and 1/8 chestnut spotted puppies? 2.) When hairless hamsters are mated with normal-haired ham

Hardy-Weinberg Equilibrium for Populations

A) Address the following Hardy-Weinberg Equilibrium problem. i) A population of iguanas on the Galapagos Islands has 20 individuals with webbed feet and 180 individuals with the dominant trait of non-webbed feet. What are the frequencies of webbed feet and non-webbed feet traits in this population? ii) H

Genetics/DNA Problems

You are studying a human disease that is inherited in an autosomal dominant fashion. You recognize that the disease maps to chromosome 10, so you obtain four DNA probes that hybridize to different chromosome 10 regions. A family in which the disease appears presents itself to a medical genetics clinic. DNA is extracted from eac

Human chromosomes and formulas; abnormal chromosome number

I am having trouble writing the formulas. I know what each X and Y chromosome each possess but I don't know who to write a formula with that. 1. Write a formula for: (a) a male with Down syndrome (due to the presence of an extra chromosome 21) (b) a female with Turner syndrome (only one X chromosome) (c) a female with cr


Consider the following artificially created yeast Ty element: See attached file for full problem description. Upstream from the element has been placed the very strong PGAL promoter which is induced by galactose added to the media. The transcript traverses the whole element (large dashed arrow). Downstream from the normal