What is a nucleotide?

A nucleotide is the monomer from which nucleic acids are made, consisting of three components: a pentose sugar, a nitrogenous base, and a phosphate group.

OCR A-Level Biology H420

Cell Structure

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Nucleotides and Nucleic Acids

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Nucleotides and Nucleic Acids

Nucleotide structure and the bases

2 things to know
Components 01, 02 and 03

Overview

The pentose sugar, phosphate group and nitrogenous base of a nucleotide, the sugars that separate DNA from RNA, and which bases are purines and which are pyrimidines.

What you need to know

Answer each one before you reveal it.

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Key term

Describe nucleotide and DNA structure.

Key term

What structural feature distinguishes purines from pyrimidines?

Questions from this subtopic

Each one with the model answer underneath.

1
What is a nucleotide?
Model answer
A nucleotide is the monomer from which nucleic acids are made, consisting of three components: a pentose sugar, a nitrogenous base, and a phosphate group.
2
Name the sugar component found in a nucleotide.
Model answer
A pentose sugar.
3
What nitrogen-containing component is present in every nucleotide?
Model answer
A nitrogenous base.
4
Which acidic group is attached to the pentose sugar in a nucleotide?
Model answer
A phosphate group.
5
Which pentose sugar is found in DNA nucleotides?
Model answer
Deoxyribose.
6
Which pentose sugar is present in RNA nucleotides?
Model answer
Ribose.

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Cell Structure

Biological Molecules

Nucleotides and Nucleic Acids

Enzymes

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Centrioles consist of .

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AA phospholipid contains one glycerol molecule.

BTwo fatty acids bond to the glycerol molecule.

COne phosphate group replaces the third fatty acid.

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Habitat means the physical place where an organism lives.

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Nucleotide structure and the bases

Overview

What you need to know

Describe nucleotide and DNA structure.

What structural feature distinguishes purines from pyrimidines?

Questions from this subtopic

What is a nucleotide?

Name the sugar component found in a nucleotide.

What nitrogen-containing component is present in every nucleotide?

Which acidic group is attached to the pentose sugar in a nucleotide?

Which pentose sugar is found in DNA nucleotides?

Which pentose sugar is present in RNA nucleotides?

Other ways to work this

What is inside Levo

The 3-step method, run for you

Cram a whole paper in one sitting

Blank Blitz makes facts automatic

Build It gets the exam shape right

Test It catches misconceptions

Brain Breaks between sessions

Every question in Nucleotides and Nucleic Acids, on a schedule.