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Flashcards in Nucleotides and Nucleic acids Deck (34)
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1

Draw, and label, the basic structure of a nucleotide.

Phosphate + pentose sugar + nitrogenous base.
They all contain the elements hydrogen, phosphorous, oxygen and nitrogen.

2

Draw a nucleotide showing the structure of the pentose sugar and where the phosphate group and
nitrogenous base attach using the standard system for numbering the carbons in the sugar.

The phosphate group attaches to the 5' (prime) carbon. The nitrogenous base attaches the 1' (prime) carbon.

3

State the two main types of nucleic acid.

Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA).

4

Draw a table to show the similarities and differences between the nucleotides of DNA and RNA.

1) Pentose Sugar: RNA = ribose, DNA = Deoxyribose
2)Purines (two rings): RNA and DNA = adenine and guamine
3) Pyrimidine (one ring): RNA = cytosine and uracil, DNA = thymine and cytosine

5

Draw the structures of ribose and deoxyribose and identify the difference between the two pentose
sugars.

Deoxyribose - there is an H below the 2' carbon
Ribose - there is an -OH group below the 2' carbon

6

List the full names of the 5 possible nitrogenous bases in nucleic acids.

Adenine (purine) , thymine (pyrimidine), guanine (purine), cytosine (pyrimidine) and uracil (pyrimidine).

7

Name the two types of nitrogenous base.

The two types are purine and pyrimidine.

8

Outline the structure of the two types of nitrogenous base.

Purines:
Larger bases which contain a double carbon ring structure.
Pyrimidines:
Smaller bases which contain a single carbon ring structure.

9

Define the term monomer.

An individual molecule that makes up a polymer.

10

Define the term polymer.

A long chain molecule composed of bonded multiple individual monomers in a repeating pattern.

11

Define the term nucleic acid.

Large polymers formed from nucleotides. They contain carbon, hydrogen, nitrogen, phosphorous and oxygen.

12

Define the terms polynucleotide.

A molecule made up of lots of nucleotides joined together in a long chain.

13

Define the term nucleotide.

The monomers used to form nucleic acids, made up of a pentose monosaccharide, a phosphate group and a nitrogenous base.

14

Define the term phosphodiester bond.

Covalent bonds formed between the phosphate group of one nucleotide and the hydroxyl group of another.

15

Draw and label a diagram to show how nucleotides can link together to form polynucleotides (including
the production of water).

The phosphate group of the second nucleotide bonds to the hydroxyl group of the 3' carbon of the pentose sugar in the first nucleotide to form a phosphodiester bond. This releases a water molecule.
This forms a long, strong sugar phosphate backbone.

16

State the name of the reaction that joins nucleotides to other nucleotides and the name of the reaction
that breaks phosphodiester bonds.

Joining: condensation reaction
Breaking: hydrolysis reaction

17

State 3 main types of activity for which cells require energy.

- Anabolic reactions such as the synthesis of large molecules (fats, polysaccharides, polypeptides ect)
- Movement e.g. protein fibres in muscle cells that cause muscle contractions.
- The transportation of ions and molecules across the membrane.

18

Draw and label a diagram of ATP. (Adenosine triphosphate)

Three phosphate groups bonded to 5' carbon of a ribose sugar. The nitrogenous base adenine is bonded 1' carbon.

19

Draw and label a diagram of ADP.

Two phosphate groups, the base adenine and ribose sugar. Bonding all in the same place.

20

List 2 similarities and 2 differences between the structure of ATP and DNA and RNA nucleotides

- RNA and ATP both have a ribose sugar, but DNA has deoxyribose
- DNA and RNA both have 1 phosphate group but ATP has 3
- They all have only one nitrogenous base.

21

Draw a reaction to show how energy is released from ATP to provide energy for cellular activities.

Energy is stored in the phosphate bond, when energy is needed ATP is broken down to ADP and inorganic phosphate. Energy is released from the phosphate bond and used by the cell.

22

Draw a diagram to show the interconversion of ATP and ADP, the names of the types of reactions
involved, where energy is released and the role of respiration.

Hydrolysis where ADP, P and energy is produced from ATP and H2O. Energy is released for use by cells.
Condensation where ATP and water is produced from ADP and P. This is when energy is supplied from respiration.

23

State 5 properties of ATP and explain why each makes it ideally suited to function as an energy transfer
molecule.

1)Small so it moves easily into, out of and within cells.
2) Water soluable - energy requiring processes happen in aqueous environments.
3) Contains bonds between phosphates with intermediate energy large enough to be useful for cellular reactions but not so large that energy is wasted.
4) Releases energy in small quantities - quantities are suitable to most cellular needs so energy isn't wasted as heat.
5) Easily regenerated- can be recharged with energy.

24

. Define the term phosphorylation.

The addition of phosphate group to a molecule.

25

Draw and label a diagram of the structure of DNA.

DNA is composed of two polynucleotide strands joined together by hydrogen bonding in a double helix shape.
The two polynucleotides are anti-parallel, this means they run in opposite directions.

26

Define the term complementary base pairing.

Specific hydrogen bonding between nucleic acid bases. So A-T/U and C-G.

27

Define the term sugar-phosphate backbone.

The sugar-phosphate backbone forms the structural framework of nucleic acids, including DNA and RNA. This backbone is composed of alternating sugar and phosphate groups.

28

Define the term anti-parallel.

Two molecules that are side by side but are arranged so that they run in opposite directions.

29

State the complementary base pairing rules, name the bond that holds them together, and state the
number of bonds that hold each pair together.

A small pyrimidine base will always bind to a purine base. Adenine-Thymine/Uracil (2 hydrogen bonds hold them together), Cytosine-Guanine (3 hydrogen bonds).

30

Explain why a DNA molecule has equal amounts of adenine and thymine and equal amounts of
cytosine and guanine

They always pair up together so you can't have one without the other.