molecular genetics

Question 1

centromere

Answer 1

point where two chromatids are linked and where the microtubules attach

Question 2

telomere

Answer 2

region of repetitive nucleotide sequences at the end of each chromatid

Question 3

chromatid

Answer 3

one copy of a duplicated chromosome, generally joined to another copy by centromere

Question 4

genes

Answer 4

small segment of DNA where its specific nucleotide sequence codes for a polypeptide with a specific amino acid sequence

Question 5

nucleotide

Answer 5

made up of one phosphate group, one pentose sugar and one nitrogenous base

Question 6

pentose sugar

Answer 6

rna: ribose sugar
dna: deoxyribose sugar

Question 7

nitrogenous base

Answer 7

DNA: Adenine, Guanine Cytosine, Thymine
RNA: Adenine, Guanine, Cytosine, Uracil

Question 8

structure of DNA

Answer 8

1. two polynucleotide chains wound around each other to form double helix
2. each strand has a sugar phosphate backbone with nitrogenous bases projected at right angles
3. nucleotides held together by strong covalent phosphodiester linkages
4. polynucleotide strands are antiparallel, one runs in the 5’ to 3’ direction, the other in the 3’ to 5’ direction
5. polynucleotide strands held together by hydrogen bonds between nitrogenous bases on opposite strands

Question 9

complementary base pairing

Answer 9

phenomenon where each type of nitrogenous base on one strand forms hydrogen bonds with a different type of base on the opposite strand

cytosine + guanine (3 H bonds)

adenine + thymine ( 2 H bonds)

Question 10

central dogma theory

Answer 10

flow of genetic information from dna through rna to protein

Question 11

transcription

Answer 11

process where a gene is copied to form piece of messenger rna

Question 12

translation

Answer 12

process where genetic information on the messenger rna is read by a ribosome to synthesize a polypeptide