In the first row of the table above, we record the initial genotypic frequencies before selection has acted. If mating has been random (an assumption of the model), the genotypes will have the Hardy–Weinberg equilibrium frequencies of p2, 2pq, and q2) In the second row of the table above, fitness values of the corresponding genotypes. In the third row the proportion of the population represented by each genotype after selection is obtained by multiplying the initial genotypic frequency times its fitness. The frequency of A allele after selection will be

#Question id: 10790

#Unit 6. System Physiology – Plant

chalcone synthase (CHS) involved in biosynthesis of phenolic compound in plants. Following are some statements regarding the action of CHS;

 a) Chalcone synthase catalyzes the conversion of p-Coumaroyl-CoA into Chalcones

 b) Substrate for Chalcone synthase is chalcone

 c) CHS activity increased by environmental factors, such as light, and fungal infection

 d) Chalcone synthase is enzyme in flavonoid biosynthesis catalyzes stepwise condensation into p-Coumaric acid by using Malonyl-CoA molecules

 Which of the following combinations of above statement is true?

#Question id: 10791

#Unit 6. System Physiology – Plant

Following are certain statements regarding furanocoumarins;

 a) furanocoumarins have an attached furan ring

 b) These compounds are toxic until they are activated by sunlight in the ultraviolet A (UV-A) region (320–400 nm)  

 c) Light activated furanocoumarins can insert themselves into the double helix of DNA and bind to the pyrimidine bases, thus blocking transcription and repair and leading eventually to cell death   

 d) Phototoxic furanocoumarins are especially abundant in members of the Umbelliferae family, including celery, parsnip, and parsley.

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

#Question id: 10792

#Unit 6. System Physiology – Plant

Compounds such as caffeic acid and ferulic acid occur in soil in appreciable amounts and have been shown,

#Question id: 10793

#Unit 6. System Physiology – Plant

Hydroxyl groups (−OH),  and methoxy groups(−OCH3) modification provides colour variations in case of

#Question id: 10794

#Unit 6. System Physiology – Plant

Which one of the following characteristics of about lignin is incorrect?

#Question id: 10795

#Unit 6. System Physiology – Plant

basic carbon skeleton of a flavonoid contains 15 carbons arranged in two aromatic rings connected by a three-carbon bridge. This structure results from two separate biosynthetic pathways: