Learn in your language
Skip to content
IGCSE · Cambridge (CIE) · 0610

Discuss sexual reproduction benefits for crop breeding

Connect new combinations, selection and a stated grower goal.

Section 16.2 · Sexual reproduction

Sexual reproduction pathway · 16.2

Extended only (Supplement); Biology 0610, 2026–2028. Use the stated specimen features and evidence. Diagrams are schematic. Written practice is self-checked

Before you begin

  • Recall DNA, inherited characteristics, nuclei and the distinction between growth and reproduction.

Work on paper. Try each question before revealing help, and explain why your method works.

Quick readiness check

Which aim can sexual crossing support?

What you will learn

  • Explain why variation can help breeding
  • Separate creating combinations from choosing useful plants

Discuss sexual reproduction benefits for crop breeding

Sexual crossing → varied inherited combinations → evaluation and selection → useful candidates for a stated crop goal. Desired outcomes are not guaranteed.Cross selected plantsCombine inherited contributionsNew combinations can resultEvaluate the offspringSelect plants meeting the goalA cross guarantees no improvementTest useful candidatesCheck performance and tradeoffsPreserving a donor is another goal
Sexual crossing → varied inherited combinations → evaluation and selection → useful candidates for a stated crop goal. Desired outcomes are not guaranteed. Original teaching model.
Sexual reproduction model reference
FeatureMeaning
CrossingCombines inherited contributions
VariationProvides breeding candidates
SelectionChooses plants meeting the goal
LimitTesting and conditions still matter

Explain why variation can help breeding

Crossing plants can bring inherited contributions together and produce new combinations among offspring. A grower seeking to combine useful traits from selected stock can use that variation as material for breeding. The sexual route therefore serves a different aim from copying one already selected donor genotype through cuttings. Name the breeding goal before comparing the methods.

Not every offspring will show the desired combination. The grower must observe or test relevant traits and select suitable plants. Crossing and selection are separate steps: one generates possible combinations, while the other chooses plants that meet the goal. Later testing under suitable conditions may be needed to judge performance, stability and unintended tradeoffs.

Separate creating combinations from choosing useful plants

Genetic variation among crop plants may also leave some suited to a specified environmental challenge. This possible benefit is conditional on useful inherited differences and the growing environment. It does not mean every diverse crop resists all pathogens, yields more or ripens together. A desired trait in one situation can be less useful in another.

For suitable species, sexually produced seeds may provide convenient planting, storage or dispersal material, but the advantage depends on seed type, viability and handling conditions. Do not claim every crop seed stores indefinitely or gives disease-free stock. A complete discussion links benefits to the crop and goal while weighing unpredictable trait combinations and production costs.

Pause and explain

Is selecting a useful offspring the same event as fertilisation?

Put the idea to work

Worked example

A grower wants useful inherited characteristics from two selected lines in offspring. Why can a cross help?

Show the worked solution
  1. Both lines contribute inherited information.
  2. Offspring can provide new combinations for selection.

Answer Crossing can produce combinations that the grower can evaluate and select.

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.

1 · Guided

Explain one sexual-reproduction benefit for a grower seeking new trait combinations.

Give me a hint

Link gamete contributions with a breeding goal.

Compare my reasoning
  1. A cross combines inherited contributions.
  2. Offspring variation provides candidates for selection.

Sexual crossing can produce new inherited combinations that a grower can assess and select for the stated breeding goal.

Look for these in your work

  • Name new combinations
  • Link variation to selection
2 · Independent

Why must useful offspring be selected and tested rather than assuming every cross is an improvement?

Give me a hint

Variation includes different outcomes.

Compare my reasoning
  1. Offspring combinations vary.
  2. Meeting the desired performance goal needs evidence.

Not every combination meets the goal; offspring need evaluation and selection, with suitable testing of performance and tradeoffs.

Look for these in your work

  • Retain varied outcomes
  • Require goal-specific evidence
3 · Transfer

Compare a grower seeking new combinations with one wanting to preserve an existing donor genotype.

Give me a hint

Match the route to the aim.

Compare my reasoning
  1. Crossing generates combinations for selection.
  2. Vegetative copying preserves an existing genotype in the model.

Crossing can support new combinations for selection; vegetative copying can preserve an already selected donor genotype. Neither aim establishes a universally best method.

Look for these in your work

  • Address both goals
  • Give a conditional comparison

Common mistakes

  • Saying every cross automatically creates the best plant.
  • Treating crossing and selection as the same step.
Recall without your notes

What can you explain now?

Is selecting a useful offspring the same event as fertilisation?

Compare with the explanation

No; selection judges the resulting plants

The origin event and later choice differ.

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

Explain a breeding benefit and separate crossing from later selection.

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.

Keep learning Biology

Course scope and assessment

780 sequenced lessons provide 2340 guided, independent and application problems in characteristics, classification, cells, organisation, specimen size, membrane transport, biological molecules, enzymes, plant and human nutrition, plant transport, circulatory systems, the heart, blood vessels, blood, disease transmission, body defences, immunity, gas exchange in humans, respiration energy uses and investigations, aerobic respiration, anaerobic respiration and recovery, excretion in humans, coordination and response, sense organs, hormones, homeostasis, tropic responses, drugs, asexual reproduction, sexual reproduction, sexual reproduction in plants, sexual reproduction in humans, sex hormones in humans, sexually transmitted infections, chromosomes, genes and proteins, mitosis, meiosis, monohybrid inheritance, variation, adaptive features, selection, energy flow, food chains and webs, nutrient cycles, population, community, ecosystem, population-growth phases, food supply, habitat destruction, pollution, conservation, biotechnology and genetic modification. 61 of 61 syllabus sections have linked teaching and staged practice. The earlier inheritance overview remains introductory, and the monohybrid pathway develops the relevant Core and Supplement requirements. This is not full programme completion or guaranteed exam readiness. Written practice is self-checked.

StudyForA · Learn with understanding

Original teaching content and links to official sources. Check your exam year and qualification before using a resource.