Lecture 5

Question 1

7 functions of nucleotides and nucleic acids

Answer 1

Energy for metabolism (ATP), enzyme cofactor (NAD+), signal transduction (cAMP), storage of genetic info (DNA), transmission of genetic info (mRNA), catalysis (ribozymes), and protein synthesis (tRNA and rRNA).

Question 2

Nucleotide composition

Answer 2

nitrogenous base, pentose, and phosphate moiety

Question 3

Nucleoside composition

Answer 3

nitrogenous base and pentose

Question 4

DNA runs in which direction

Answer 4

5’ to 3’

Question 5

Ribose vs deoxyribose position

Answer 5

Ribose: OH in 2’ carbon
Deoxyribose: H in 2’ carbon

Question 6

Phosphate moiety is attached to which carbon

Answer 6

5’ Carbon

Question 7

Where does the nitrogenous base attach?

Answer 7

1’ carbon

Question 8

Another name for the 1’ Carbon on a pentose

Answer 8

anomeric carbon

Question 9

Beta designation

Answer 9

5’ moiety and 1’ base are in the same plane, either both above or both below

Question 10

Alpha designation

Answer 10

5’ moiety and 1’ base are in opposite planes

Question 11

NMP

Answer 11

Nucleo monophosphate

Question 12

NDP

Answer 12

Nucleo diphosphate

Question 13

NTP

Answer 13

Nucleo triphosphate

Question 14

D designation

Answer 14

If the OH goes to the right on the most distal carbon in a fischer projection

Question 15

L designation

Answer 15

If the OH goes to the left on the most distal carbon in a fischer projection

Question 16

Fischer projection bond directions - horizontal vs vertical

Answer 16

horizontal - coming out of the page

vertical - going into the page

Question 17

Heteroaromatic molecules

Answer 17

multiple different bases are present in the composition of the ring structure

Question 18

Nucleobases UV light absorption

Answer 18

250-270 nm

Question 19

Pyrimidine bases

Answer 19

Cytosine (DNA), Thymine (DNA), and Uracil (RNA)

Question 20

Purine bases

Answer 20

Adenine and guanine

Question 21

Type of bond formed between the nitrogenous base and the anomeric carbon

Answer 21

N-glycosidic bond

Question 22

Bond formed position in pyrimidines

Answer 22

N1

Question 23

Bond formed position in purines

Answer 23

N9

Question 24

Syn conformation

Answer 24

bulk of the nitrogenous base is over the sugar

Question 25

Anti conformation

Answer 25

bulk of the nitrogenous base is not over the sugar and swung opposite

Question 26

Adenine's nucleoside and nucleotide

Answer 26

Nucleoside: adenosine Nucleotide: adenylate

Question 27

Guanine's nucleoside and nucleotide

Answer 27

Nucleoside: guanosine Nucleotide: guanylate

Question 28

Cytosine's nucleoside and nucleotide

Answer 28

Nucleoside: cytidine Nucleotide: cytidylate

Question 29

Thymine's nucleoside and nucleotide

Answer 29

Nucleoside: Thymidine Nucleotide: Thymidylate

Question 30

Uracil's nucleoside and nucleotide

Answer 30

Nucleoside: Uridine Nucleotide: Uridylate

Question 31

Common modification performed after DNA synthesis

Answer 31

methylation

Question 32

Epigenetic marker

Answer 32

way to mark own DNA to prevent degradation and also way to mark which genes should be active

Question 33

Inosine

Answer 33

sometimes found in the "wobble position" of the anticodon in tRNA. Deamination of adenosine. attaches at N9

Question 34

Pseudouridine

Answer 34

found in tRNA (stabilization) and rRNA (folding). Attaches where the methyl group would be in Uracil. Made from uridine by enzymatic isomerization after RNA synthesis. Attaches at C5

Question 35

type of bond formed in covalent bonds of polynucleotides

Answer 35

5' to 3' phosphodiester

Question 36

Why is RNA less stable than DNA

Answer 36

the 2' OH makes it less stable under alkaline conditions

Question 37

A-T # of hydrogen bonds

Answer 37

2

Question 38

G-C # of hydrogen bonds

Answer 38

3

Question 39

of base pairs per DNA turn

Answer 39

10.5

Question 40

Replication of genetic code

Answer 40

strand separation which then serves as a template for a new strand. Synthesis is catalyzed by DNA polymerases and will have one daughter strand and one parent strand

Question 41

mRNA structural properties

Answer 41

Made of ribose. Single stranded. Polycistronic

Question 42

Monohybrid cross

Answer 42

cross differing in one characteristic

Question 43

F1

Answer 43

First filal generation. Shows the dominance

Question 44

F2

Answer 44

Second filal generation

Question 45

Phenotype

Answer 45

the physical characteristic or appearance

Question 46

Genotype

Answer 46

genetic make up of alleles

Question 47

Mendel's 5 propositions

Answer 47

Hereditary determinants of particulate nature (genes); each adult pea has 2 particles for each character studied (alleles); Each particle segregates equally into the gametes; Each gamete carries only 1 particle (allele); and gametes can combine without regard to which particle is carried

Question 48

Mendel's 1st Law

Answer 48

Each particle separates (segregates) equally into the gametes (egg and sperm)

Question 49

Allele

Answer 49

one of the different forms of a gene that can exist. Alleles differ in DNA base sequences

Question 50

Number of chromosomes

Answer 50

46 chromosomes per cell. 44 autosomes and 2 sex chromosomes

Question 51

Chromosome

Answer 51

consists of one covalently connected DNA molecule and associated proteins

Question 52

Introns

Answer 52

Do not encode the polypeptide sequence and thus are removed

Question 53

Introns in bacterial chromosomes

Answer 53

interrupt mainly tRNA sequences

Question 54

Transposons

Answer 54

the fact that a DNA sequence is not completely static. Sequences can move around within a genome

Question 55

Percentage of the total genome that encodes proteins

Answer 55

1.5%

Question 56

Telomeres

Answer 56

Cap the ends of linear chromosomes

Question 57

Centromere

Answer 57

hold the sister chromatids together during mitosis.

Question 58

Hayflick limit

Answer 58

belief that human cells can divide about 52 times before the telomeres are shortened too much to allow further division.

Question 59

Nucleosomes

Answer 59

consist of DNA wrapped around positively charged histone proteins (His, Lys, Arg) since DNA backbone is negatively charged.