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TLS Online TPP Program

#Question id: 7090

In what way, if any, does the chromosomal determination of sex differ in Drosophila and humans?

#Unit 5. Developmental Biology
  1. In humans, the Y chromosome determines maleness, with female development being a default state, but in Drosophila, the presence of two X chromosomes determines femaleness, and male development is the default state.
  2. In humans, the Y chromosome determines maleness, but in Drosophila, the ratio of X chromosomes to autosomes determines maleness or femaleness.
  3. In humans, it is the presence of only one X chromosome that triggers male development, and two X chromosomes trigger female development, just as occurs in Drosophila.

  4. In human males, a single Y chromosome is present in the absence of an X chromosome, while in Drosophila, a single X chromosome is present in the absence of a Y chromosome.

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TLS Online TPP Program

#Question id: 16108

#Unit 7. System Physiology – Animal

What is the result of a rise in body temperature?
TLS Online TPP Program

#Question id: 15653

#Unit 13. Methods in Biology

You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. You have isolated a mutation that causes constitutive melibiase activity, which you designate MelA–. P1 phage mapping experiments using a Tn5 insertion linked to Mel1 show that MelA– is not linked to Mel1. Moreover you find that when an amber suppressor is introduced into a MelA– mutant, normal melibiase regulation is restored. Classify the MelA– mutation on the basis of genetic properties,  make a proposal for the type of regulatory functions affected by the MelA– mutation?
TLS Online TPP Program

#Question id: 10383

#Unit 6. System Physiology – Plant

The nitrogenase enzyme complex fixes N2 produces ammonia, The nitrogenase enzyme complex catalyzes this reaction by following characteristics given below;

a) It can be separated into two components—the Fe protein and the MoFe protein— neither of which has catalytic activity by itself

b) Fe protein is the smaller of the two components and has two identical subunits, each contains an iron–sulfur cluster, which participates in the redox reactions

c) The Fe protein is irreversibly inactivated by O2 while MoFe protein is activated by O2

d) MoFe protein has four subunits, each subunit has two Mo–Fe–S clusters

e) Ferredoxin serves as an electron donor to the Fe protein, and Fe protein reduces the MoFe protein without any hydrolysing ATP

f) Only prokaryotes have nitrogenase enzyme

Which of the following characteristics of nitrogenase enzyme complex is incorrect?
TLS Online TPP Program

#Question id: 12586

#Unit 10. Ecological Principles

A biome with dry and rainy seasons, trees in patches, and ground cover of tropical bunchgrass is called a
TLS Online TPP Program

#Question id: 29027

#Unit 11. Evolution and Behavior

Which of the following is not the characteristics of fixed action pattern?