Chapter 4, Nucleic acids and an RNA World

Question 1

Deoxyribonucleic acid (DNA)

Answer 1

Stores genetic information and is replicated using proteins

Question 2

RNA world hypothesis

Answer 2

Proposes that there was a stage in the evolution of life when ribonucleic acid both stored the genetic information and catalyzed its own replication

Question 3

Central component of every nucleotide

Answer 3

Sugar/Phosphate group or PO4

Question 3

ribonucleotides

Answer 3

Monomers of RNA , nucleotide that consists of a ribose sugar, one or more phosphates, and one of four nitrogenous containing bases: adenine, guanine, cytosine, or uracil

Question 4

Difference between ribonucleotides and deoxyribonucleotides

Answer 4

Basically have the same structure other but while both the sugars have an -OH group bonded to the 3’ carbon, the ribonucleotide has an OH bonded to the 2’ carbon while the deoxyribose has an H’ at the same place. Basically just one oxygen atom

Question 5

deoxyribonucleotides

Answer 5

Monomers of DNA, Nucleotide consisting of deoxyribose sugar, one or more phosphates, and one of four nitrogen-containing bases, adenine, guanine, cyosine or thymine

Question 6

Ribose

Answer 6

five-carbon sugar found in RNA. Alternated with phosphate groups to form the backbone of the RNA polymer and binds to nitrogenous bases

Question 7

Nitrogenous bases

Answer 7

adenine and guanine, cytosine and thymine. (adenine is a purine that bonds with thymine) and guanine is a purine that forms with cyotosine the pyrimidine.)

Question 8

Purines

Answer 8

Adenine and guanine (Note: Purines are larger than pyramidines) It has two rings

Question 9

Pyramidines

Answer 9

cytosine (C), uracil (U), and thymine (T)

Question 10

Uracil

Answer 10

Nitrogenous pyramidine base used by ribonucleotides

Question 11

Thymine

Answer 11

Nitrogenous pyramidine acid used by deoxyribonucleotides

Question 12

Nucleic acids

Answer 12

Macromolecule used by cells to store or transmit hereditary info. The two types of nucleic acids are ribonucleotides (RNA) and deoxyribonucleotides (DNA)

Question 13

nucleotides

Answer 13

They’re the monomers that make up the nucleic acids and the two types of deoxynucleotide and ribonucleotide. Molecule that consists of 5 carbon sugar (ribose or deoxyribose), one or more phosphate groups and one several nitrogenous bases

Question 14

phosphodiester linkage

Answer 14

Chemical linkage between adjaent nucleotide residues in DNA and RNA. FOrms when the phosphate group of one nucleotide condenses with the hydroxyl group on the sugar on another molecule.

Question 15

adenosine triphosphate (ATP)

Answer 15

Provides energy needed for DNA and RNA synthesis, example of activated nucleotide.

Question 16

How is ATP made

Answer 16

The potential energy of nucleotide monomers is raised by reactions that adds two additional phosphate groups to the 5’ phosphates of ribonucleoside or deoxyribonucleoside

Question 17

Primary structure of DNA

Answer 17

sugar phosphate backbone, created by phosphodiester linkages, sequence of any of four nitrogenous bases

Question 17

X-ray crystallography

Answer 17

A technique for determining the three dimentsional structure of large molecules, including proteins and nucleic acids

Question 18

Purine Pyramidine pairing difference

Answer 18

Adenine forms two hydrogen bonds with thymine while guanine forms three hydrogen bonds with cytosine

Question 19

Double stranded DNA

Answer 19

backbones run in antiparallel directions.

Question 20

Complementary base pairing

Answer 20

arragngements of nucleotide bases so that purine bond with pyramidines.

Question 21

Anti parallel

Answer 21

Describes opposite orientation of nucleic acid strands that are hydrogen bonded to one another. One strand running in the 5’ –> 3’ direction and the other in the 3’ –> 5’ direction.

Question 22

Double helix

Answer 22

2 anti parallel strands twisted into double helix. Stabliilized by hydrogen bonding between the complementary base pairs, hydrophobic interactions and van der Waals interactions.

Question 23

DNA tertiary structure

Answer 23

2 types of DNA tertiary structure
1. When DNA is wound too tightly or looselyu it can twist on itself tto form compact three dimensi0onal structures called supercoils
2. DNA in the cells of eukaryotes and certain achea will form teriary structures by wrapping around specilized DNA binding porteins called histones.

Question 23

How DNA makes a copy of itself

Answer 23

1. Hydrogen bonds holding 2 strands of DNA break
   Step 2: deoxyribonucleotiedes form hydrogen bonds with complementary bases on the original strand of DNA. Then their phosphate groups form phosphodiester linkages to create a new strand

Question 24

template strand

Answer 24

strand of RNA or DNA used to make new complementary strand via complementary basing

Question 25

Complementary strand

Answer 25

A strand of RNA or DNA with a base sequence. It forms from complimentary basing with the template strand

Question 26

2 significant differences between DNA and RNA

Answer 26

1. The sugar in sugar-phosphate backbone of RNA is ribose, not deoxyribose as in DNA.
2. The pyrimidine base thymine does not exist in RNA, RNA instead contains uracil, a closely related pyrimidine base.
   The Hydroxyl group (OH) on the RNA makes it more reactive and less stable than DNA

Question 27

RNA secondary structure

Answer 27

Purine and pyrimidine in RNA undergo hydrogen bonding with complementary bases on the same strand

Question 28

RNA tertiary structure

Answer 28

Arises when secondary structures fold into more complex shapes

Question 29

What RNA can do

Answer 29

Messenger RNA: Transmits info needed to synthesize proteins
Regulates the production of messenger RNA
Catalyze the synthesis or proteins

Question 30

Ribozymes

Answer 30

Any RNA molecule that can act as a catalyst to increase the rate of a chemical reaction