LECTURE 3 - Biopolymers

Question 1

DIRECTION ENDS IN NUCLEIC ACIDS

Answer 1

Nucleic acids: 5’ to 3’ (five prime to three prime – from numbering around
the sugar)
5’-ATGACCTGCGGATCAGGATTTGGTGGG-3’

Question 2

DIRECTION ENDS IN AMINO ACIDS

Answer 2

Proteins: N-terminus (or amino terminus) to C-terminus (or carboxy terminus)
(N)-MTCGSGFGGRAFSCISACGPRPGRCCIT-(C)

NH2 to the COOH

Question 3

repeating units (backbones and sidechains or bases) nucleic acids.

Answer 3

• Nucleotide building blocks
• phosphate, sugar, base/nucleobase
• Common sugar-phosphate
  backbone
• Negative charge on phosphates
• Hydrophilic (sugars and phosphates)
• 5’ and 3’ ends
• “Acid” because of the phosphate
  groups

Question 4

repeating units (backbones and sidechains or bases) proteins.

Answer 4

• Amino acid building blocks
• Common peptide backbone
• Sidechains (R) of the different amino acids differ

Question 5

Appreciate and explain the evidence for DNA as the source of genetic
information.

Answer 5

In the experiments conducted by Frederick Griffith and later confirmed by Avery, McCarty, and MacLeod:

The DNA in the heat-killed virulent bacteria contained genetic information: When Griffith conducted his experiments, the DNA in the heat-killed virulent bacteria retained the genetic information necessary to transform non-virulent bacteria into virulent ones. This DNA carried the instructions or information for specific traits related to virulence.

The DNA from the heat-killed bacteria was transferred into the harmless bacteria: When Griffith mixed the heat-killed virulent bacteria with live, harmless bacteria, some genetic material (DNA) from the heat-killed bacteria was transferred into the harmless bacteria. This transfer resulted in the genetic transformation of the harmless bacteria into virulent ones, as they adopted the genetic information from the heat-killed bacteria.

In this way, the DNA in the heat-killed bacteria was demonstrated to contain genetic information, and this information was transferred to the harmless bacteria, leading to a change in their genetic traits. This process provided strong evidence that DNA is the molecule responsible for carrying and conveying genetic information.

https://www.khanacademy.org/science/biology/dna-as-the-genetic-material/dna-discovery-and-structure/a/classic-experiments-dna-as-the-genetic-material

Question 6

RNA vs DNA

Answer 6

RNA : single strand, no thymine, smaller in size, temporarily carries genetic information, less stable than DNA