Question

BI X , X A.D.A . Normal 1 No Spac. Heading 1 Heading 2 Title Font Paragraph Styles 7. Which of the following is NOT true? a) An amino acid that is essential in humans, must be essential in all other organisms. b) An amino acid that is essential in humans, may be non-essential in other primates. C) An amino acid that is essential in humans under one set of circumstances, may not be essential in other situations. d) An amino acid that is essential in humans is not essential because we can't make it, only, but because we can't make it and we needed to make PROTEINS e) An amino acid CANNOT be essential because it is either strictly ketogenic or partially glucogenic (or both). 8. Which of the following is true? a) An amino acid that is non-essential in humans, must be non-essential in all other organisms b) An amino acid that is essential in humans, must be non-essential in other primates. c) An amino acid that is essential in humans under one set of circumstances, may not be essential in other situations. d) An amino acid that is non-essential in humans, is not needed to make PROTEINS. e) An amino acid CANNOT be essential because it is either strictly ketogenic or partially glucogenic (or both). 9. Which of the following does NOT correctly complete this statement: "A non essential amino acid in humans..."? a) may be made in humans from scratch', ie, from nitrogen, methane, and CO2. b) is still needed to make proteins. c) may be made in humans from pyruvate or Krebs Cycle intermediates and other amino acids. d) may be made in humans from pyruvate or Krebs Cycle intermediates and parts of other amino acids e) be used to make the nitrogenous bases of nucleotides. 10. Which of the following is NOT correct? a) Amino acids are used in all organisms to make proteins. b) Certain amino acids are used in humans to make the nitrogenous bases of nucleotides, c) Certain amino acids are used in humans to make the non-steroidal, non-eicosanoid hormones and neurotransmitters d) Amino acids are needed in all cells as an alternate energy source when carbohydrates and lipids are gone. e) dll proteins made in humans contain essential and non-essential amino acids. here to search o f 199. e a

Answer 1

Ans 7) option a.

Essential amino acids are those which need to be taken through diet and our body can't prepare it metabolically.Although most eukaryotes have similar essential amino acids, but it is not necessary that if one amino acid that is essential in humans is also essential in other organisms too. Because inability to synthesise amino acids is the consequence of evolution during which some of the genes synthesizing those amino acids which were abundant in nature are turned off according to varying niche of organism,

Ans. 8 ) option C is correct.

Such amino acids are called 'Conditionally Essential'

For eg. Arginine, cysteine, tyrosine, glycine etc.

Ans. 9 ) option a.

Human body does not allow inorganic biosynthesis of amino acids from precursors like nitrogen, carbon di oxide and methane. It would require exceptionally high energy as confirmed by Miller-Urey experiment.

And. 10 option E.

It's not compulsory for all proteins to contain Essential as well as non essential amino acids.