Nucleic Acids - Structure and Function 6

Question 1

necessary for enzymes that attach amino acids

Answer 1

3D arrangement of tRNAS

Question 2

are found in nucleus of cells that appear to play roles in both gene regulation and in cellular defenses

Answer 2

siRNAs

Question 3

True or False: Hydrogen bonds between the bases of each strand that, like the hydrogen bonds in proteins, can be broken with heat and urea

Answer 3

True

Question 4

Single strands absorb light at _____ more strongly than double strands

Answer 4

260 nm

Question 5

single strands absorb light more strongly than double strands

Answer 5

hyperchromic effect

Question 6

consequence of the disruption of interactions among stacked bases

Answer 6

hyperchromic effect

Question 7

Denatured duplexes can readily renature when the temperature is

Answer 7

lowered below the melting temperature

Question 8

What are processes that are important for the technique known as the Polymerase chain reaction?

Answer 8

strand separation and rehybridization

Question 9

strand separation of DNA duplexes is achieved by

Answer 9

heating to boiling

Question 10

requires single stranded primers to find matching sequences on the template DNA and form a duplex

Answer 10

Hybridization

Question 11

What are the different considerations for efficient hybridization (annealing)?

Answer 11

temperature
salt concentrations
strand concentration
magnesium ion levels

Question 12

largest macromolecule in a cell

Answer 12

DNA

Question 13

molecular weight of a single chromosome in a small bacterial cell

Answer 13

1 billion Daltons

Question 14

If DNA of human chromosomes from a single cell are taken, how long would it be?

Answer 14

7 feet long

Question 15

True or False: eukaryotes have chromatin system to package enormous molecules in nucleus

Answer 15

True

Question 16

True or False: Bacteria fo not have histone proteins that DNA wrap around

Answer 16

True

Question 16

Bacteria do not have histone proteins that DNA wrap around, but they do have proteins that help organize the DNA in the cell-mostly by making looping structures, these proteins are known as ____________

Answer 16

Nucleoid Associated Proteind

Question 17

What are the Nucleoid Associated Proteins?

Answer 17

HU
H-NS
Fis
CbpA
Dps

Question 18

most resembles eukaryotic histone H2B and binds to DNA non-specifically

Answer 18

HU

Question 18

play a role in helping to regulate transcription and respond to DNA damage. They may also be involved in recombination

Answer 18

Nucleoid Associated Proteins

Question 19

In bacteria, there is no nucleus for DNA, thus it contained a structure called

Answer 19

nucleoid

Question 20

the nucleoid contains about ________ DNA with much of the remainder comprised of RNAs and transcription factors

Answer 20

60%