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1. Explain why a well-adapted organism synthesizes only the proteins necessary at any particular moment. 2. When radioactive uracil is injected into the developing larvae of Drosophilia, only certain regions of the chromosomes in certain tissues contain radioactive uracil. Explain this observation.

Biology Questions

1. If farmers continue to use large quantities of chemicals to control insect pests and weeds what problem (from an evolutionary perspective) are they likely to encounter? 2. In terms of gene pools, what is a major potential consequence of isolating wildlife in reserves. 3.Tay-Sachs disease, which is inherited as a Men

Phenotypic Ratios

What are the expected phenotypic ratios for a monohybrid cross? For a dihybrid cross? For a sex-linked trait? See attached file for full problem description.

Mendel's Law & Chromosomal Basis of Inheritance

Compare Mendel's laws of heredity with the chromosomal basis of heredity. Reflect on why comparing Mendel's work with the chromosomal basis of heredity suggests that the work of science is cumulative.

Genetic Food Modification

1. Write a report, providing a brief overview of the debate surrounding genetic food modification. 2. Utilizing information from the Internet, include in the report the process by which transgenic organisms are created. In your description, address the following questions: ? How is this process similar to the more traditiona

SNP linkage

You are trying to map a human gene thought to be involved in cat allergies. Because you know this gene is on chromosome 20, you decide to examine the linkage of several SNPs located on chromosome 20 with respect to the gene involved in cat allergies. You have obtained DNA from 10 individuals and know whether they are allergi

Physical Personality Trait Associated with Criminal Behavior

Describe a physical trait(s) of trait theories associated with criminal behavior, and give an example of a recent criminal who exhibits this trait. might this crime be prevented in future circumstances. Supplemented with an article that highlights the relationship between genes, environmental and criminal behavior.

Questions involving genes

1. Alternate forms of a gene that govern the expression of the same trait and that occur at the same positions on homologous chromosomes are called: a. Chromatids. b. mRNA. c. Gametes. d. Alleles. e. Autosomes. 2. In Mendel's garden peas, the yellow color is dominant to the green. Additionally

Chromosome mapping and coefficient of coincidence.

In the fruit fly, Drosophila melanogaster, a spineless (no wing bristles) female fly is mated to a male that is claret (dark eyes) and hairless (no thoracic bristles). Phenotypically wild type F1 female progeny were mated to fully homozygous (mutant) males and the following progeny (1000 total) were observed.

Genetics Problem

Three loci, mitochondrial malate dehydrogenase that forms a and b (MDHa, MDHb), glucouronidase that has forms 1 and 2 (GUS1, GUS2), and a histone gene that has + and - variants(H+, H-), are located on chromosome #7 in humans. Assume that the MDH locus is at position 35, GUS at position 45, and H at position 75. A female whose

Chromosome Mapping

Assume that investigators crossed a strain of flies carrying the dominant eye mutation Lobe on the second chromosome with a strain homozygous for the second chromosome recessive mutations smooth abdomen and straw body. The F1 Lobe females were then backcrossed with homozygous smooth abdomen, straw body males and the following p

Chromosome Mapping

Assume that the genes for tan body and bare wings are 15 map units apart on chromosome II in Drosophila. Assume also that a tan-bodied, bare-winged female was mated to a wild type male and the resulting F1 phenotypically wild type females were mated to tan-bodied, bare- winged males. Of 1000 offspring, what would be the expe

Genetic Problems - Lethal Gene

1. A short-tailed mutant of mouse was discovered. Multiple crosses of this mouse to normal mice produced 27 normal, long-tailed mice and 25 short-tailed mice. A series of crosses among short tailed mice were made and 21 short-tailed mice and 11 long-tailed mice were produced. Determine which phenotype is dominant and explain

Introductory Genetics Problem Set

1. Two black guinea pigs were mated repeatedly over several years. They produced 29 black progeny and 9 white progeny. Explain these results, giving the genotypes of parents and progeny. 2. In horses, black is dependent on a dominant gene (B) and chestnut upon its recessive allele (b). The trotting gait is due to a dominan

Genetics - Genotypes, Punnett Squares

In fruit flies, the phenotype for eye color is determined by a certain locus. E indicates the dominant allele and e indicates the recessive allele. The cross between a male wild type fruit fly and a female white-eyed fruit fly produced the following offspring. Wild-type Wild-type White-eyed White-eyed Brown-eyed male f

Human Nutrition

How does one's food pattern over time contribute to the development of diseases? What do you think is the interplay between genetics and eating habits? How early should one be concerned with preventing diseases? Infancy?


Using the table below, build a genetic distance matrix which gives the total number of genetic differences between pairs of unique haplotypes in the sample. The first box is filled in for you, by way of an example. Haplotypes 1 2 3 4 5 1 -- 2 2 -- 3 -- 4 -- 5

Recombinant Mapping Curly Wings

If Curly wings are recessive to normal wings and Barred Eyes is recessive to normal eyes, cross Curly Barred to a normal normal fly. What would be the expected ratios if they were linked or unlinked? If you had 2,500 flies, how many would you expect to see?

Genotypes and frequencies of phenotypes

In a particular species of guppy, tails can either be long or short and either feathered or straight. A cross between a true-breeding long, feather-tailed male guppy and a true-breeding short, straight-tailed female guppy produces progeny that all have short, straight tails. a) express the genotypes of the adults in the cr

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