Asexual reproduction — the two-element definition
Asexual reproduction is a process resulting in the production of genetically identical offspring from one parent, with no fusion of gamete nuclei and no fertilisation. Both elements score: "genetically identical" AND "one parent". The offspring are clones. Mitosis is the underlying nuclear division — it copies genetic material exactly, so repeated mitotic division from a single parent yields identical offspring. "Similar to the parent" or "looks the same" earns nothing.
Examples — binary fission, tubers, runners
Bacteria divide by binary fission: one cell copies its genetic material and splits into two identical daughter cells. Tubers (e.g. potato): each "eye" on the swollen underground stem grows into a new identical plant. Runners/stolons (e.g. strawberry): a horizontal stem forms rooted plantlets that can separate from the parent. Recognition rule: offspring arising from one organism's own body part, with no pollen, flower, gamete or zygote shown, is asexual.
(Extended) Speed bought with uniformity
For: only one parent is needed, so numbers rise rapidly in favourable conditions and no mate must be found; for crops, every plant is genetically identical to a parent of known quality, so yield is predictable at scale. Against: no genetic variation, so every individual shares one vulnerability — a new disease, pest or environmental change can wipe out the population, and in a crop monoculture it can destroy the entire field. Name the mechanism, not just "risky".
Drawn from real examiner reports.
Identical ≠ "similar to the parent"
Mark schemes want the exact wording: a process producing genetically identical offspring from one parent. "An organism makes copies of itself" or "offspring that look like the parent" scores nothing — resemblance is not genetic identity. State both elements every time, even when the question looks as though it wants only a short sentence.
Mitosis does not create variation
Asexual reproduction runs on mitosis, which copies genetic material exactly and produces genetically identical cells. Meiosis is the division that generates variation, and it makes gametes. Candidates have written that mitosis increases genetic variation — that reverses the whole basis of asexual reproduction and of this topic.
Flagged w22 P12 Q35 — mitosis stated to increase variation
Runners and tubers described as "seeds"
A strawberry runner or a potato tuber involves no flower, no pollen and no fertilisation — the new plant grows directly out of the parent's own tissue. Writing that the tuber "produces seeds", or that the runner is "pollinated", turns a correct identification into a wrong one. No gamete fusion means asexual.
Seed formation labelled asexual
The reverse error: candidates call seed formation asexual because the new plant "looks the same" as a parent. A seed grows from a fertilised ovule, so gamete nuclei have fused — that is sexual reproduction (16.2), whatever the offspring resembles. Appearance never decides the classification; fertilisation does.
One-sided "discuss" answers
(Extended) "Discuss the advantages and disadvantages" demands both sides. Answers listing only advantages, or only disadvantages, cap themselves well below full marks. The syllabus also names two contexts — a wild population and crop production — so cover both rather than writing one general answer and hoping it stretches.
"It is risky" with no mechanism
(Extended) Bare judgement words earn nothing alone — examiners made exactly this point on pyramid-of-biomass answers, where "more accurate" by itself was not credited. Say why: no genetic variation, so every individual is equally susceptible, so a single disease can take the whole population or crop.
Flagged s23 P31 Q5d — bare judgement word not credited
Pair every claim with its cause
Each point needs its mechanism attached: "only one parent is needed, so numbers rise rapidly"; "no genetic variation, so the whole crop is equally vulnerable". The "so..." clause is usually where the mark actually sits.
Two elements, every time
For "describe" or "define": genetically identical offspring, from one parent, no fusion of gametes. Two elements, and dropping either usually drops a mark. It costs one extra clause and it is the most reliable mark in 16.1.
Ask: has fertilisation happened?
That one question settles every "identify the type of reproduction" item. Look for pollen, a flower, an ovule, a zygote or two parents. Find none of those, and see a new individual growing from a dividing cell, a tuber or a runner, and the answer is asexual.
(Extended) Plan all four cells
A discuss question has two contexts and two sides: advantage and disadvantage for a wild population, then advantage and disadvantage for crop production. Sketch all four before writing and a one-sided answer becomes impossible. The full grid is in the study note above.
Asexual reproduction is a process resulting in the production of genetically identical offspring from one parent. There is no fusion of gamete nuclei and no fertilisation.
The genetic identity of the offspring follows from mitosis — the type of nuclear division that copies genetic material exactly before a cell (or organism) divides, producing genetically identical daughter cells. Asexual reproduction relies on repeated mitotic-type division (or the growth of a new individual from an existing body part), not on the fusion of two gametes.
Definition trap: "the offspring look similar" is NOT sufficient — you must state the offspring are genetically identical, and that only one parent is involved.
Define asexual reproduction.
(a) Describe asexual reproduction.
(b) State ONE named example of asexual reproduction in a plant, naming the structure involved.
