Sexual reproduction uses gametes from two parents, so offspring vary. Asexual reproduction uses one parent and no gametes, so offspring are genetically identical to it. That one sentence carries most of the marks in a comparison question.
This lesson builds on seed and fruit formation and prepares the ground for cell division and inheritance.
What are the two routes?
Plants can make new plants in two different ways.
| Feature | Sexual | Asexual |
|---|---|---|
| Parents | Two (or one plant that self-pollinates) | One |
| Gametes and fertilisation | Yes | No |
| Offspring | Genetically different from each other and the parents | Genetically identical to the parent (clones) |
| Speed | Slower: flowers, pollination, seeds, germination | Usually faster: part of the plant grows directly |
| Spread | Seeds can be dispersed far away | New plants usually stay close to the parent |
| Needs a pollinator | Yes (insect, wind or another flower) | No |
Examples of asexual reproduction include runners on strawberry plants, tubers on potatoes and bulbs on onions.
Why does the difference in offspring happen?
The gametes carry half the genetic information of each parent. Fertilisation joins one random male nucleus with one random female nucleus. The result is a new mix, so each seed is different.
In asexual reproduction, cells divide to make exact copies of the parent’s cells. Nothing is mixed, so the new plant matches the parent. The inheritance model board shows this mixing in a fictional one-gene model, and it is a model, not a prediction for any real plant.
Worked example
A farmer has one banana-type plant with excellent fruit and resistance to a particular soil disease. She wants 100 plants with the same qualities.
Should she grow them from seed or use pieces of the plant? Explain, and state one risk of her choice.
Step 1, which route gives identical offspring? Asexual reproduction, since one parent gives genetically identical clones.
Step 2, apply it: growing new plants from pieces of the parent copies her excellent fruit and the disease resistance into every plant.
Step 3, risk: all 100 plants are genetically identical, so a new disease that the plant is weak against could affect all of them at once.
Answer: use pieces of the plant (asexual), because offspring are clones with the same features; the risk is that the whole crop shares the same weakness.
The mistake to watch for
A common slip is to state a difference with no reason.
Mistaken answer: “Asexual reproduction is quicker and sexual reproduction is better.”
The student gave an opinion with no biological link, and “better” is not a scientific term.
The correction is to say what each route produces and what that allows: asexual reproduction is quicker because no gametes, pollination or fertilisation are needed, and sexual reproduction produces variation because two parents contribute different genes. A variation helps a species survive a change in the environment.
Check yourself
Answer on paper, then open each answer.
1. Why are offspring from asexual reproduction genetically identical to the parent?
Show answer
One parent supplies all the genetic material, and cells divide by mitosis to make exact copies. There is no mixing of genes from a second parent.
2. Give one advantage of sexual reproduction for a wild plant species in a changing climate.
Show answer
It produces variation, so some offspring may have features that let them survive the change. The species is more likely to continue.
3. A gardener grows 30 potato plants from tubers of a single plant. Are the new plants clones or siblings grown from seed? Explain.
Show answer
Clones. Tubers are a form of asexual reproduction, so each new plant is genetically identical to the parent.
Where this leads next
Next, see how the seeds themselves are tested in interpreting germination results. If you like comparison questions but still drop marks on the reasoning, our teachers practise that in online one-to-one Biology tuition.