TLS Online TPP Program

#Question id: 15153


In this problem we will explore some of the many ways that mutations in two different genes can interact to produce different Mendelian ratios. Consider a hypothetical insect species that has red eyes. Imagine mutations in two different unlinked genes that can, in certain combinations, block the formation of red eye pigment yielding mutants with white eyes. In principle, there are two different possible arrangements for two biochemical steps responsible for the formation of red eye pigment. The two genes might act in series such that a mutation in either gene would block the formation of red pigment. Alternatively, the two genes could act in parallel such that mutations in both genes would be required to block the formation of red pigment.
Further complexity arises from the possibility that mutations in either gene that lead to a block in enzymatic activity could be either dominant or recessive. If the crosses is made between a wild type insect with red eyes and a true breeding white eyed strain with mutations in both genes. Such considerations yield the Pathways in parallel with recessive mutations in both genes, determine the phenotype of the F1 progeny and the expected phenotypic ratio of red to white eyed insects in the F2.

#Unit 8. Inheritance Biology
  1. F1 will have red eyes

    Phenotypic ratio in F2 will be 1 white:15 red

  2. F1 will have red eyes

    Phenotypic ratio in F2 will be 3 white: 13 red

  3. F1 will have red eyes

    Phenotypic ratio in F2 will be 1 white:15 red

  4. F1 will have whit eyes

    Phenotypic ratio in F2 will be 9 white: 7 red

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TLS Online TPP Program

#Question id: 10322

#Unit 6. System Physiology – Plant

some of the enzyme of citric acid cycle with its co-factor given in below;


             ENZYMES

           CO-FACTOR

                  INHIBITORS

s) Citrate synthase

i) TPP

a) NADH

t) Succinate dehydrogenase

ii) NAD+

b) Monofluoroacetyl-CoA

u) Isocitrate dehydrogenase

iii) Co-A

c) Aresenite, Succinyl CoA, NADH

v) Malate dehydrogenase

iv) FAD

d) ATP

w) α-ketoglutarate dehydrogenase complex

v) NADP+, Mg2+, Mn2+

e) Malonate, Oxaloacetate

Find out the correct combination of Enzymes with its co-factor and inhibitor.

TLS Online TPP Program

#Question id: 10313

#Unit 6. System Physiology – Plant

Which of the following enzyme are found in the inner membrane of mitochondria?

TLS Online TPP Program

#Question id: 10311

#Unit 6. System Physiology – Plant

A succinate dehydrogenase is one of the enzyme of TCA cycle, which is also known as Respiratory complex II. It is competitively inhibited by;

TLS Online TPP Program

#Question id: 10310

#Unit 6. System Physiology – Plant

Which of the following enzyme in the kreb’s cycle function as an allosteric enzyme found in matrix space?

TLS Online TPP Program

#Question id: 10309

#Unit 6. System Physiology – Plant

Which of the following carbon compound also called the oxoglutarate? 

TLS Online TPP Program

#Question id: 10308

#Unit 6. System Physiology – Plant

Oxidative decarboxylation of pyruvate to acetyl-CoA by the PDH complex, how the pyruvate dehydrogenase complex carries out the five consecutive reactions in the decarboxylation and dehydrogenation of pyruvate?

 A) Pyruvate reacts with the bound thiamine pyrophosphate (TPP) of pyruvate dehydrogenase, undergoing decarboxylation to the hydroxyethyl derivative

 B) A transesterification in which the —SH group of CoA replaces the —SH group of E2 to yield acetyl-CoA and the fully reduced (dithiol) form of the lipoyl group

 C) The reduced FADH2 of E3 transfers a hydride ion to NAD1 , forming NADH, the enzyme complex is now ready for another catalytic cycle

 D) The transfer of two electrons and the acetyl group from TPP to the oxidized form of the lipoyllysyl group of the core enzyme, dihydrolipoyl transacetylase, to form the acetyl thioester of the reduced lipoyl group

 E) Dihydrolipoyl dehydrogenase promotes transfer of two hydrogen atoms from the reduced lipoyl groups of E2 to the FAD prosthetic group of E3 , restoring the oxidized form of the lipoyllysyl group of E2

 Find out the correct sequence of action of this complex enzyme?