Environmental factors such as photoperiod and temperature can alter the levels of active gibberellins by affecting gene transcription for specific steps in the biosynthetic pathway such as;

a) Promotion of germination by light has been shown to be due to increases in GA1 levels resulting from a light-induced increase in the transcription of the gene for GA3ox, which converts GA20 to GA1

b) level of GA20-oxidase occurs in the highest amount in shoot tips and elongating stems, is increased under long-day conditions.  The fact that GA 20-oxidase is the enzyme that converts GA53 to GA20

c) Giving cold treatment  of Thlaspiarvense and a return to high temperatures, the ent-kaurenoic acid is converted to GA9, the most active gibberellin for stimulating the flowering response

d) Potato plants overexpressing the GA20ox gene showed tuberization, whereas transformation with the antisense gene for GA20ox inhibited tuberization

Which of the following from the given above statements is correct?

TLS Online TPP Program

#Question id: 17808

#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. What is the probability that a child will be albino if: One parent is a non-albino member of Generation 2, and the other parent is a non-albino member of Generation 1.

TLS Online TPP Program

#Question id: 17809

#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. What is the probability that a child will be albino if: Both parents are members of Generation 2, and one parent is albino and the other is non-albino.

TLS Online TPP Program

#Question id: 17994

#Unit 8. Inheritance Biology

Consider a heritable autosomal disease with an incidence in the population of 1 per thousand. On average, individuals with the disease have 80% as many children as the population average. In answering the various parts of this question, assume that mating is random. What mutation rate would be required to maintain the observed incidence of the disease in the population if the disease is dominant?

TLS Online TPP Program

#Question id: 17995

#Unit 8. Inheritance Biology

Consider a heritable autosomal disease with an incidence in the population of 1 per thousand. On average, individuals with the disease have 80% as many children as the population average. In answering the various parts of this question, assume that mating is random. What mutation rate would be required to maintain the observed incidence of the disease in the population if the disease is recessive?

TLS Online TPP Program

#Question id: 17996

#Unit 8. Inheritance Biology

Consider a heritable autosomal disease with an incidence in the population of 1 per thousand. On average, individuals with the disease have 80% as many children as the population average. In answering the various parts of this question, assume that mating is random. Now assume that the mutation rate is zero, that the disease is recessive, and that the disease allele is maintained in the population by heterozygote advantage. Calculate the heterozygote advantage,

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.