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TLS Online TPP Program

#Question id: 787

Which of the following statement is INCORRECT with respect to the structure of DNA?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. Six adenosines in a row in a DNA helix produce a bend of about 18 degrees.

  2. DNA was first isolated and characterized by Friedrich Miescher who called the phosphorus-containing substance “nuclein.”

  3. It is the pentoses that define the identity of a nucleic acid not the nitrogenous bases.

  4. The Z-DNA tracts do not play any role in regulating the expression of some genes or in genetic recombination.

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TLS Online TPP Program

#Question id: 17268

#Unit 8. Inheritance Biology

In humans, albinism (unpigmented skin, hair, and eyes) is due to an enzymatic deficiency, and it is an autosomal recessive trait. Suppose that in a small country of one million people (“Generation 1”), there are 500 aa albinos and 9000 Aa heterozygous carriers. Estimate p, the frequency of allele A, in Generation 1?
TLS Online TPP Program

#Question id: 17267

#Unit 8. Inheritance Biology

In humans, albinism (unpigmented skin, hair, and eyes) is due to an enzymatic deficiency, and it is an autosomal recessive trait. Suppose that in a small country of one million people (“Generation 1”), there are 500 aa albinos and 9000 Aa heterozygous carriers. Estimate q, the frequency of allele a, in Generation 1. Show your calculations. 
TLS Online TPP Program

#Question id: 15659

#Unit 8. Inheritance Biology

You calculate map distances between genes A, B, and C based on all pairwise dihybrid crosses. When you perform the trihybrid cross to verify your results, you discover that, despite analysis of a very large number of progeny, you have only about half as many double crossover progeny as you expect. Which explanation is the most reasonable?
TLS Online TPP Program

#Question id: 15002

#Unit 8. Inheritance Biology

If you performed a dihybrid cross and found that your results were significantly different from the 9:3:3:1 ratio, what would you suspect?
TLS Online TPP Program

#Question id: 15001

#Unit 8. Inheritance Biology

You cross true breeding lizards that are either green or albino and discover that all the offspring are striped green and white. Which is the most likely result if you cross two striped lizards?
TLS Online TPP Program

#Question id: 15000

#Unit 8. Inheritance Biology

I do a chi square analysis of the offspring from my cross of a black mouse and albino mouse. If the black mouse was heterozygous I should have expected a 1:1 ratio, and I got 6 albino and 2 black mice. What is my chi square value?