15 recall questions · Biology only (B): not in Science (Double Award). Answer from memory, reveal the answer, then rate yourself. Ratings stay on this device.
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Embryonic stem cells can differentiate into any type of cell; adult stem cells (for example in bone marrow) can form only a limited range of cell types.
Key words: embryonic · adult · bone marrow
Risk of rejection by the immune system, uncontrolled division forming tumours, infection from the culture, and ethical objections to destroying embryos.
Key words: rejection · tumours · ethical
A cell able to self-renew and differentiate into one or more specialised cell types.
Key words: stem cell
Able to form all embryonic and extra-embryonic cell types needed for a complete organism.
Key words: totipotent
Able to form almost any body-cell type.
Key words: pluripotent
Able to form a limited range of related cell types.
Key words: multipotent
An immune response against transplanted cells recognised as non-self.
Key words: immune rejection
A controlled study in people used to evaluate safety and effectiveness.
Key words: clinical trial
Potential advantages: Pluripotent; extensive self-renewal; can generate many body-cell types. Limitations or concerns: Embryo ethics, immune rejection, differentiation control and tumour risk.
Key words: Embryonic stem cells
Potential advantages: Established uses such as bone-marrow transplantation; patient cells may reduce rejection. Limitations or concerns: Usually multipotent, sometimes difficult to isolate and expand, invasive collection.
Key words: Adult stem cells
Potential advantages: Pluripotent and potentially patient-matched without using an embryo. Limitations or concerns: Reprogramming may introduce abnormalities; differentiation and tumour risks remain.
Key words: Induced pluripotent stem cells
False. Very early embryonic cells may be totipotent; established embryonic stem cells are usually pluripotent.
False. Potential treatments require evidence from controlled trials and long-term safety monitoring.
False. They may reduce immune rejection, but contamination, mutation, faulty differentiation and tumour risks remain.
False. Ethics concerns values and rights; biological disadvantages concern safety and function. Both can inform a judgement.
