OCR A 2.1.6(h)–(m) · 19 written questions · 35 marks · about 40 minutes · marked as you go
This free quiz has 19 written exam questions on cell differentiation and stem cells, all taken from OCR A Level Biology A papers (AS and A level, 2017 to 2025). Short answers and calculations mark themselves. For longer answers you write your answer, then tick off the OCR mark-scheme points you made, so you see exactly where the marks are. This quiz covers the second half of OCR A 2.1.6: how cells are specialised, how they are organised into tissues and organs, what stem cells are, how blood cells and xylem and phloem are produced from stem cells, and how stem cells could be used.
What the quiz covers (OCR A spec 2.1.6(h)–(m))
Specialised cells (2.1.6(h)): erythrocytes, neutrophils, sperm cells, palisade cells, ciliated epithelium and guard cells.
Tissues, organs and organ systems (2.1.6(i)): the difference between a tissue and an organ, and applying it to blood and leaves.
Stem cells (2.1.6(j)): the features of stem cells and what 'pluripotent' means.
Blood cells from bone marrow (2.1.6(k)): where neutrophils and erythrocytes come from and how they differ.
Xylem and phloem from meristems (2.1.6(l)): the role of meristem tissue and how vascular tissue is produced.
Uses of stem cells (2.1.6(m)): medical research, treating neurological conditions and the pros and cons of induced pluripotent stem cells.
How to use it
Write every answer in full, as you would in the exam: the mark for each question is shown, so you know how much to write. When you self-mark, only tick a point if your answer clearly makes it, then read the examiner's tip under each question. Your progress is saved on your device, so you can do it in two sittings, and at the end you can retry just the questions where you dropped marks.
Prefer multiple choice? Try the 16-question Cell Differentiation and Stem Cells multiple choice quiz first.
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Where students lose marks (from OCR examiners' reports and mark schemes)
Each point below is followed by wording that gained marks.
Biconcave, not concave: Students often wrote 'concave' for the shape of an erythrocyte, leaving off the 'bi', which OCR ignores.
✔ Gains credit: Erythrocytes are biconcave, which increases their surface area to volume ratio.
Space for haemoglobin, not oxygen: Many said that having no nucleus gives an erythrocyte more space for oxygen.
✔ Gains credit: With no nucleus or organelles there is more space for haemoglobin.
The acrosome contains enzymes: Some described the acrosome as an enzyme, and called the outer layers of the egg a membrane or cell wall.
✔ Gains credit: The acrosome contains hydrolytic (digestive) enzymes that let the sperm penetrate the outer layer of the ovum.
Ciliated cells don't make mucus: Many students assumed ciliated epithelial cells make mucus.
✔ Gains credit: Goblet cells secrete mucus; the cilia on ciliated epithelial cells waft the mucus along.
Different cells, not different tissues: Asked why blood is a tissue, many wrote that blood is made of similar cells doing a similar job, ignoring the different cell types in the micrograph.
✔ Gains credit: Blood is made of different types of cell (e.g. erythrocytes and neutrophils) but not different tissues, so it is a tissue, not an organ.
Pluripotent is not multipotent: Many gave the definition of multipotent when asked for pluripotent, and few mentioned cell 'types' or extra-embryonic tissues.
✔ Gains credit: Pluripotent stem cells can differentiate into any type of body cell, but cannot form a whole organism or extra-embryonic tissues such as the placenta.
Undifferentiated isn't enough: Saying stem cells are 'undifferentiated' on its own often didn't score: OCR wanted what they can do, or a second feature.
✔ Gains credit: Stem cells can differentiate into many specialised cell types and can divide continually by mitosis (self-renewing).
Dopamine is a chemical, not a cell: Some said stem cells could differentiate into dopamine, and many jumped from 'become nerve cells' straight to 'cures Parkinson's'.
✔ Gains credit: Stem cells differentiate into nerve cells that replace the dead dopamine-producing cells in the brain, so dopamine levels rise again.
Keep practising
Try the Cell Differentiation and Stem Cells multiple choice quiz, the Cell Division quiz, the Cell Cycle, Mitosis and Meiosis written quiz or the Exchange Surfaces and Ventilation written quiz, or browse all our OCR A Level Biology quizzes. Our OCR A masterclasses (Year 12 on Wednesdays at 5.15pm, Year 13 on Tuesdays at 6.30pm) work through real exam questions on one topic each week.
Questions, mark schemes and examiners' report extracts © OCR.