Question

36. Which statement is true about Nucleic Acids? a) DNA is a protein b) DNA is identical to RNA C) RNA has the structure of a double helix, d) RNA binds to DNA but not to amino acids. e) None of these are true. 37. Which is true for DNA, RNA and Polypeptides? a) They all have R groups, b) They are formed from ribose by dehydration synthesis. c) They all have subunits that include nitrogenous bases. d) They were formed (first appear) during Chemical Evolution before life. e) All are true. 38. The DNA molecule: a) has a curved structure that forms a stable helix.), b) contains Uracil, c) is made from nucleotides that include ribose d) has the same nitrogenous bases as RNA, e) all these choices are true. 39. The following is a synthesis sequence or progression that is a hypothesis for Chemical evolution: elements, ionic and covalent bonding to form simple molecules, simple organic monomers, dehydration synthesis to form bio polymers, formation of micelles (Pre cells). This concept a) can only be observed in living cells, b) is a theory that proves that life could not evolve on other planets. c) is a hypothetical model that can be confirmed in the laboratory, d) is a hypothesis that has no supporting evidence from rocks that pre date the presence of cells in the fossil record. e) These are all true. 40. Polypeptides, DNA and RNA are important in the process of Chemical Evolution. The properties that they share are: a) They are long complex polymers, b) They have groups with shapes and charges that hang off the chain c) They each have the ability to interact with (bind to other molecules because of their attached groups (With shapes with charge profiles), D) All are correct. E) None are true. 41. During "Chemical Evolution", why are phospholipids important? a) They are living cells, b) They let molecules pass into and out of the micele. c) The phosphate head makes the bi layer repel water. d) The Fatty Acid layer lets ionic molecules pass through. e) The Fatty Acid layer separates the inside water environment from the outs de water environment 42. During Chemical Evolution, what would one expect to find inside the Proto cell (pre cell)....inside the phospholipid bilayer? a) Water mixed with many non-polar molecules. b) Fatty Acids mixed with non-polar molecules. c) Many different ionic and polar molecules dissolved in water. d) Functioning proteins, E) Living single celled organisms

Answer 1

Q.36. Answer- e) none of these are true

Explanation- DNA is nucleic acid not a protein. DNA is not identical to RNA because RNA contains ribose sugar and uracil but DNA contains deoxyribose and thymine.RNA is single stranded not double stranded helix. RNA can bind with proteins to form ribonucleoproteins.

Q.37. Answer- d) They were formed (first appear) during chemical evolution before life

Explanation- DNA and RNA contains nitrogen bases and polypeptide contains R-groups. All of these biomolecules are formed during chemical evolution before life has evolved as cell.

Q.38. Answer- c) is made from nucleotides that include ribose

Explanation- DNA is polymer of nucleotides and nucleotide is basic unit of DNA. Nucleotide is made from ribose sugar, phosphate group and nitrogen base. DNA contains adenine, thymine, guanine and cytosine nitrogen bases but do not contain uracil.

Q.39. Answer- b) is a theory that proves that life could not evolve on other planets

Explanation- chemical evolution can only occur on earth because earth is only planet that has liquid water and the environment during chemical evolution is devoid of oxygen so that biomolecules are formed . These biomolecules combines to form a single cell . Due to unique features of earth than other planets life could not evolve on other planets.