book- appendix

Question 1

DNA vs RNA bases

Answer 1

DNA: A/T, G/C

RNA: A/U, G/C

Question 2

DNA replication

Answer 2

in nucleus via DNA polymerase and helicase; semiconservative

Question 3

mitosis vs meiosis

Answer 3

Mitosis produces two genetically identical “daughter” cells from a single “parent” cell, whereas meiosis produces cells that are genetically unique from the parent and contain only half as much DNA.

mitosis: chromosomes divide for growth, repair, asexual reproduction

meiosis: gamete production (sperm and egg)

mitosis: 46 –> 46 (2n –> 2n)
-diploid
-get 2 identical cells

meiosis: 46–> 23 (2n –> 1n)
-halpoid
-get 4 genetically unique cells

Question 4

how are DNA and RNA made? which bonds?

Answer 4

chains of nucleotides via 3’, 5’ phosphodiester bonds

negatively charged phosphates of nucleic acids make up the hydrophilic backbone

Question 5

which direction is DNA transcribed?

Answer 5

5’ to 3’ (for DNA replication and transcription)

RNA polymerase reads the DNA template strand in the 3′ → 5′ direction
➝ This allows synthesis of mRNA in the 5′ → 3′ direction

The new RNA strand is complementary and antiparallel to the DNA template strand.

Question 6

DNA leading vs lagging strand transcription

Answer 6

Leading strand: synthesized continuously in the 5′ → 3′ direction toward the replication fork

Lagging strand: synthesized discontinuously in Okazaki fragments (still 5′ → 3′) away from the replication fork

Question 7

what holds the 2 strands of DNA together

Answer 7

hydrogen bonds between the purine base on one strand and complementary pyrimidine base on opposite strand

Question 8

purines vs pyrimidines

Answer 8

purines: adenine, guanine
“pure as gold”
-double ringed

pyrimidines: cytosine, thymine (DNA), uracil (RNA)
“CUT”
- single ring (“pyramids have one base”)

Question 9

types of RNA

Answer 9

mRNA- messenger; for translation into proteins

tRNA- transfer amino acids in translation, has a anticodon to match mRNA

rRNA- ribosomal; catalyze peptide bond formation

snRNA- splicing; remove introns

miRNA/siRNA = inhibitor, regulate gene expression post-transcriptionally

“mRNA is the message, tRNA transfers, rRNA is the ribosome.”

Question 10

which RNA has anticodon to match codon on mRNA

Answer 10

tRNA