4 (a) Use words from the box to complete the sentences - Edexcel - GCSE Biology - Question 4 - 2013 - Paper 1
Question 4
4 (a) Use words from the box to complete the sentences.
carbon
chromosome
double
gene
triple
hydrogen
A DNA molecule consists of two coiled strands that form a **... show full transcript
Worked Solution & Example Answer:4 (a) Use words from the box to complete the sentences - Edexcel - GCSE Biology - Question 4 - 2013 - Paper 1
Step 1
Use words from the box to complete the sentences.
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Answer
A DNA molecule consists of two coiled strands that form a double helix.
The strands are held together by hydrogen bonds between the bases.
A gene is a section of a DNA molecule that codes for a specific protein.
Step 2
Which two scientists were the first to build a 3D model of a DNA molecule?
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Answer
The two scientists who were the first to build a 3D model of a DNA molecule are James Watson and Francis Crick.
Step 3
Describe how two proteins can be different shaped molecules.
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Answer
Two proteins can differ in shape due to variations in their amino acid sequences, which influence their folding patterns. This can lead to distinct functional shapes that affect how they interact with other molecules.
Step 4
Suggest what may have happened to the DNA to cause a protein to form the wrong shape.
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Answer
A mutation in the DNA sequence may have occurred, leading to the incorporation of the wrong amino acids during protein synthesis. This alteration can affect the protein's folding and ultimately its shape.
Step 5
Complete the sentence by putting a cross (X) in the box next to your answer.
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Answer
Enzymes are
A biological catalysts.
Step 6
State the term used to describe organisms that have identical DNA.
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Answer
The term used to describe organisms that have identical DNA is 'clones'.
