Explain vitamin C sources and connective-tissue support
Relate a vitamin source to a function without calling it fuel.
Section 7.1 · Diet
Exam scope and assessment notes
Core and Extended · Biology 0970, 2026–2028. Use the stated specimen features and evidence. Diagrams are schematic. Written practice is self-checked; human subject-teacher review, supervised practical competence and cumulative assessment remain pending. Cambridge states that IGCSE 0970 has the same subject content as IGCSE 0610, with 9–1 grading. This StudyForA pathway maps the 2026–2028 syllabus only. This 9–1 graded qualification is available only in a limited number of administrative zones. Confirm that your centre can enter you for this code and exam series with Cambridge International. Cambridge has published a separate syllabus for 2029. StudyForA has not reconciled that version yet; this page supports exams in 2026, 2027 and 2028 only.
Before you begin
- Recall large and small nutrient molecules, cell membranes and enzyme specificity.
- Use the stated diagram keys and evidence; models are not to scale.
Work on paper. Try each question before revealing help, and explain why your method works.
Quick readiness check
Which is a useful vitamin C source?
What you will learn
- Relate a vitamin source to a function without calling it fuel.
- Limit a deficiency inference to the evidence supplied.
Compare vitamin C and vitamin D
| Component | Examples of sources | Role |
|---|---|---|
| Vitamin C | Citrus fruit, peppers | Connective tissue; deficiency: scurvy |
| Vitamin D | Oily fish; labelled fortified foods | Calcium use; deficiency: rickets |
Use suitable food sources
Citrus fruit, peppers and many fresh fruits and vegetables supply vitamin C. The source and preparation affect the amount present. Vitamins are needed in small amounts for body functions; they do not replace carbohydrate or fat as energy-yielding fuel.
Vitamin C supports collagen formation and healthy connective tissues, including the tissues involved in wound healing. A food can supply both vitamin C and other nutrients.
Connect deficiency with a cause
A prolonged lack of adequate vitamin C can cause scurvy. Poor connective-tissue maintenance can contribute to symptoms such as bleeding gums and poor wound healing. The syllabus requires the deficiency cause, not a diagnosis from one isolated symptom.
In a supplied historical case with a documented diet missing vitamin C, link the deficiency to the function. Do not infer that every case of sore or bleeding gums is scurvy or recommend supplement doses.
Pause and explain
Which missing component causes scurvy?
Worked example
A documented diet contains no adequate vitamin C source over a prolonged period. Name the associated deficiency disease and the relevant tissue function.
Show the worked solution
- Name vitamin C deficiency.
- Name scurvy.
- Connect it to collagen/connective tissue.
Answer Prolonged vitamin C deficiency can cause scurvy by impairing normal connective-tissue support.
Try a topic test
Choose Easy, Normal or Difficult. Save your answers and open worked review after finishing.
Test this topic →From guided practice to a new situation
Write your answer and reasoning first. Use a hint only if you are stuck. The model solution is for self-checking; your written work is not automatically marked.
State two vitamin C sources and one function.
Give me a hint
Choose fruit and vegetables.
Compare my reasoning
- Name citrus fruit and peppers.
- Connect to connective tissue/wound healing.
Citrus fruit and peppers; vitamin C supports healthy connective tissue and wound healing.
Look for these in your work
- Two sources.
- Specific function.
Why is “vitamin C releases the same fuel energy as starch” misleading?
Give me a hint
A vitamin supports functions without being the main fuel.
Compare my reasoning
- Starch supplies glucose after digestion.
- Vitamin C has a connective-tissue role.
Vitamin C supports body functions; it is not the main energy-yielding carbohydrate fuel.
Look for these in your work
- Separate nutrient roles.
- No fuel equivalence.
An image shows bleeding gums with no dietary history. Can it alone prove scurvy? Explain.
Give me a hint
Several causes can produce a symptom.
Compare my reasoning
- Dietary adequacy is unknown.
- The symptom is not unique.
- More appropriate evidence is needed.
No; the image alone does not establish vitamin C deficiency or a diagnosis.
Look for these in your work
- State the evidence limit.
- Retain the correct deficiency association.
Common mistakes
- Vitamin C is not the main energy fuel.
- One symptom is not a unique diagnosis.
What can you explain now?
Which missing component causes scurvy?
Compare with the explanation
Vitamin C.
This is the named deficiency cause.
After trying it yourself, choose your next review. This is your self-assessment.
Your review choice appears on Today. Sign in to sync it across devices.
Make it stick
Connect vitamin C, connective tissue and scurvy in one causal account.
If you needed the solution, close it and solve the problem again from a blank page. A correct answer is stronger when you can explain the reason for each step.