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TLS Online TPP Program

#Question id: 11551

Polypeptides can have which of the following types of effects?

I) autocrine

II) paracrine

III) endocrine

#SCPH28 | Zoology
  1. only I and III
  2. only II and III
  3. only I and II
  4. I, II, and III
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TLS Online TPP Program

#Question id: 10797

#I Life Science/ Life Sciences Group – I-V

The colored pigments of plants are of two principal types: carotenoids and flavonoids. Given below some statements of about these pigments;

 a) Anthocyanins are colored flavonoids that attract animals

b) Flavonoids are phenolic compounds that include a wide range of colored substances

c) Carotenoids are coloured terpenoid compounds that also serve as accessory pigments in photosynthesis

d) most widespread group of pigmented carotenoids is the anthocyanins, these are glycosides that have sugars. Without their sugars, anthocyanins are known as anthocyanidins

Which of the following is incorrect statements of these pigments;
TLS Online TPP Program

#Question id: 18081

#SCPH01 Biochemistry

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: 15652

#SCPH01 Biochemistry

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 in terms of its basic genetic properties, 
TLS Online TPP Program

#Question id: 5538

#SCPH28 | Zoology

The first truly vertebrate phase of development is manifested by the formation of the
TLS Online TPP Program

#Question id: 3858

#SCPH28 | Zoology

The 5' methyl guanosine caps added during RNA chain elongation performs what function?

1. prevents degradation by nucleases 

2. are recognized by protein factors

3. are used to identify the type of RNA