3.1.5.1 Structure of DNA and RNA Flashcards Preview

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Flashcards in 3.1.5.1 Structure of DNA and RNA Deck (23)
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1
Q

What are the types of nucleic acid?

A

DNA (deoxyribonucleic acid)

RNA (ribonucleic acid)

2
Q

What are nucleotides made of?

A

A pentose sugar (has 5 carbon atoms)
A phosphate group
A nitrogen-containing organic base (includes Cytosine, Thymine, Uracil, Adenine and Guanine)
These parts are joined by a condensation reaction

3
Q

What is a single nucleotide called?

A

A mononucleotide

4
Q

How do you join two nucleotides together?

A

A condensation reaction between a deoxyribase sugar and a phosphate group
For each mole of dinucleotide formed, one mole of water is formed
Called a dinucleotide
Joined by a phosphodiester bond

5
Q

What is a chain of nucleotides called?

A

A polynucleotide

6
Q

What are the parts of DNA/RNA called?

A
Phosphate
Pentose sugar
Adenine
Guanine
Cytosine
Thymine 
Uracil
7
Q

What is RNA?

What are its bases?

A

Polymer, single chain, relatively short, polynucleotide chain, pentose sugar is ribose, organic bases are adenine, guanine, cytosine and uracil

8
Q

What are the types of RNA?

A

tRNA: Transfers information from DNA to the ribosomes
mRNA: Makes up ribosomes alongside protein
Involved in protein synthesis

9
Q

What is DNA?

What are its bases?

A

Pentose sugar is deoxyribose, organic bases are A, T, G and C

10
Q

Which bases are complimentary for DNA/RNA?

A

Adenine pairs with thymine

Guanine pairs with cytosine

11
Q

What is the structure of DNA?

A

The two polynucleotide chains wind around eachother to form a double helix which forms the structural backbone
Pentose sugars are anti-parallel (in the opposite direction)

12
Q

What carbons in deoxyribonucleic acid join with what?

A

Carbon 5 joins to a phosphate above it

Carbon 3 joins to a phosphate below it

13
Q

In DNA, what is the backbone called?

A

A sugar phosphate backbone

14
Q

What joins bases in DNA/RNA together?

A

Hydrogen bonds

15
Q

How many hydrogen bonds occur between the bases in DNA?

A

A and T: two, represnted by ‘=’

C and G: three, represented by three lines, stronger

16
Q

What breaks up a dinucleotide?

A

A hydrolysis reaction

17
Q

What is the function of DNA?

A

To give us variation
To give us our physical characteristics- phenotype
DNA gives us proteins then proteins give us our pheontype

18
Q

What makes DNA more robust?

A

More C to G bonds as there is an extra hydrogen bond which makes it stronger

19
Q

How does DNA’s structure relate to its function?

A

Very stable structure: rarely mutates
Two strands: allows it to seperate during DNA replication and protein synthesis
Extremely large molecule: carries an immense amount of genetic information
Base pairs within the helical cylinder: genetic information is partly protected from being corrupted by outside chemical/physical forces
Base pairing: DNA can replicate and transfer information as mRNA

20
Q

Why is DNA a polymer?

A

Because it has repeating monomers

21
Q

How many bases are needed to code for one amino acid?

A

3

22
Q

Why can a polypeptide have more bases than it needs?

A

Because some parts of DNA don’t code for proteins

Sometimes it is mutated

23
Q

What is the structure of a nucleotide?

A

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