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Corn Kernel Genotypes and Phenotypes

A) While examining an ear of corn, you notice that the kernels in the ear display two apparent phenotypes; yellow and white. inspired by your understanding that these represent different alleles of a single gene, you count the kernels of each type and you asses 347 yellow (Y) kernels and 111 white (y) kernels. if this ear of c


In humans, the ability to taste PTC is inherited as a dominant gene (T; Taster). in a marriage between two heterozygous tasters (Tt): a) what is the probability of 3 taster children? b)what is the probability of 3 taster girls? c)if they have 5 children, what is the probability that the first 3 will be tasters and the last

% of traits passed to progeny

The average pea pod contains about 7 peas. The gene for smooth peas is dominant over the gene for wrinkled peas. If heterozygous pea pods grown from smooth peas are self-fertilized and all of the pods have 7 peas, what percentage of the pods will have: a) all smooth peas? b) 5 smooth and 2 wrinkled peas?


Describe a single gene inherited disease, a multi-factorial (multiple genes and environmental factors) disease, and non-inherited genetic disease. Use Down syndrome, sickle-cell anemia, asthma and breast cancer as examples


What is parental imprinting? What is the result of replacing the sperm nucleus of a fertilized egg with another egg nucleus?

Genetic probabilities

49% of the population has a particular gene. A test has been developed that can determine if a person has this gene or not. The test has a false positive (says the person has the gene when they don't) rate of 6%, and a false negative rate of 3%. What is the probability that a random person will test positive to having this gene


Vinblastine is a drug that interferes with the assembly of microtubules. It is widely used for chemotherapy in treating cancer patients whose cancer cells are actively dividing to form tumors. Suggest a hypothesis to explain how vinblastine slows tumor growth. Assuming that albinism is under the control of a si

Phobias, Alzheimer's Disease & Memory

#1 Phobias Introduction: Your best friend has just called you with some great news! The president of the company that your friend works for has asked your friend to make a speech at the next stockholder's meeting. When you congratulate your friend, however, your friend tells you that a terrible fear of public speaking may

Debates: Deception, Male and Female Brain & Stem Cell Debate

#1 When Is a Lie Not a Lie? The issue of some psychological research using deception in order to gather information. This is often done in social psychology experiments where it is necessary to "set up" a situation in order to study individuals' responses. At the conclusion of the study, participants are always told the tr

Genetically Altered Foods are overviewed.

Nowdays lots of food that get on our table are genetically altered. Some people are not bothered by that fact. Some demand more facts supporting that such foods are safe to eat and will not bring any negative alterations to our health later. The effects of GM foods are noted.

Life on earth (biological concepts from the non-science major perspective)

1. When comparing the DNA molecule to a twisted ladder, what do the rungs of the ladder represent? 2. Describe the three major properties of genes that are explained by the structure of DNA? 3. What occurs on the sex chromosomes to determine the sex of a mammal? 4. Describe a difference between meiosis and mitosis?

Life on earth (biological concepts from the non-science major perspective)

Hemophilia is a sex-linked trait in humans. That means that the gene that is responsible for it resides on the X chromosome. Hemophilia is a hereditary disorder characterized by the failure of the blood to clot properly. As a result, such individuals suffer from excessive bleeding. Sometimes it results in death. Here are th

A Hardy Weinberg inquiry is solved.

In a population that is in Hardy-Weinberg equilibrium, 16% of the population shows a recessive trait. What is the frequency of the dominant allele (p) in the population?

Hardy Weinberg Problem

Assume that left-handedness is a recessive trait controlled by one pair of dominant-recessive alleles. If 625 of 2,500 individuals in a sample of a population is left-handed, and if the population is in Hardy-Weinberg equilibrium, how many individuals in the entire population of 10,000 would be predicted to be heterozygous for

Rabbit phenotypes are discussed.

Consider the following hypothetical genetics information for cottontail rabbits: Ear length is controlled by one pair of co-dominant alleles (E = allele for long ears; E' = allele for short ears) located on rabbit chromosome #11. Eye color is controlled by one pair of dominant and recessive alleles (H = dom. for hazel eyes; h

Hemophilia is predicted.

If hemophilia is an X-linked recessive trait, what percent of the daughters would be expected to be carries of the disease if a hemophiliac man had children with a woman who was a carrier of the disease? Predictions occur.

Blood types

A man with Type O blood has children with a woman who has Type AB blood. what blood types would represent the full range of possible phenotypes in children that the man and woman might have together

Red - green colorblindness

A colorblind woman marries a man with normal color vision. What percentage of their sons would be expected to be coloblind, what percentage of their daughters would be ecpected to be colorblind explain answers about sons and duarghters that would be expected to be colorblind in genetic words.

Y-linked trait

Is it possible to have a Y-linked trait that affects females? why or why not?

Genotype of a particular chipmunk is debated.

In a captive colony, he selects a male chipmunk with short ears. Without any additional information, would the geneticist know the genotype of that particular male chipmunk? If yes, what would the short-eared chipmunk's genotype be. If no, how could the geneticist determine the genotype of that particular chipmunk? Ideas are i

Heterozygoous genotypic and phenotypic ratios are determined.

In peas, color (yellow or green peas) and seed texture (smooth or wrinkled ) obey Mendelaian laws. Yellow is dominant over green, and smooth is dominant over wrinkled. A pea plant heterozygous for both traits is crossed with a plant that has green wrinkled peas. What are the expected genotypic and phenotypic ratios in the offs

Hemophilia is predicted.

If a woman is a carrier for hemophilia and has a child with a man who does not have hemophilia, what percentage of their sons would be expected to have hemophilia? What percentage of their daughters would be expected to be carriers of the gene for hemophilia? Ideas are expressed.

Genotypes and phenotype ratios

What would be the expected genotypic and phenotypic ratios in the f1 and f2 generations, if flower color in carnations is controlled by co-dominant alleles and you begin with the P generation using pure, or true-breeding, carnations that have different (red & white) flower colors?