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TLS Online TPP Program

#Question id: 180

Which of the following statements about aromatic amino acids is correct?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. All are strongly hydrophilic.

  2. Histidine’s ring structure results in its being categorized as aromatic or basic, depending on pH.

  3. On a molar basis, tryptophan absorbs more ultraviolet light than tyrosine.

  4. The major contribution to the characteristic absorption of light at 280 nm by proteins is the phenylalanine R group.

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TLS Online TPP Program

#Question id: 18080

#Unit 9. Diversity of Life Forms

The following are all adaptations to life on land except
TLS Online TPP Program

#Question id: 18081

#Unit 8. Inheritance Biology

The interaction of selection and inbreeding in determining the incidence of autosomal recessive diseases. Consider a gene in which recessive mutations occur at a rate of 10-5. Assume a selective disadvantage S of 0.4 in homozygotes for the recessive allele. What is the frequency of the recessive allele (q). And calculate the incidence of the disease. Assume random mating.
TLS Online TPP Program

#Question id: 18082

#Unit 8. Inheritance Biology

The interaction of selection and inbreeding in determining the incidence of autosomal recessive diseases. Consider a gene in which recessive mutations occur at a rate of 10-5. Assume a selective disadvantage S of 0.4 in homozygotes for the recessive allele. Now assume that, for thousands of generations, 10% of all children have been products of first-cousin matings (the remaining 90% being products of random matings). Calculate the steady-state value of q. Also calculate the incidence of the disease at steady state. 
TLS Online TPP Program

#Question id: 18083

#Unit 8. Inheritance Biology

The interaction of selection and inbreeding in determining the incidence of autosomal recessive diseases. Consider a gene in which recessive mutations occur at a rate of 10-5. Assume a selective disadvantage S of 0.4 in homozygotes for the recessive allele. Would q be expected to rise, fall, or remain unchanged during the first 10 generations after the cessation of inbreeding, Briefly justify your answer. What numerical value would q approach after thousands of generations with no inbreeding?
TLS Online TPP Program

#Question id: 18087

#Unit 13. Methods in Biology

Each of five questions on a multiple-choice examination has four choices, only one of which is correct. The student is attempting to guess the answers. The random variable X is the number of questions answer correctly. Probability that the student will get
Exactly three correct answers
TLS Online TPP Program

#Question id: 18088

#Unit 13. Methods in Biology

If a coin is tossed 5 times, then consider the following statements:
I: Probability of getting exactly 2 heads is 5/16.
II: Probability of getting at least 4 heads is 3/16.
III: Probability of getting at most 2 heads is 5/8.
Which one of the following is correct in respect of the above statements