Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A yeast cell buds and makes a daughter. A pair of sisters is born to the same parents. Which pair do you expect to differ more, and why? Give the source of variation in each case.
Heredity passes on a common basic design and small changes in it. DNA copying is never perfect, so asexual reproduction makes a little variation. Sexual reproduction mixes the DNA of two parents and makes far more. Variations build up over generations, and one that helps survival is more likely to be passed on.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The yeast. Budding is asexual. The daughter differs from the parent only by small changes made in copying DNA.
Step 2. The sisters. Each sister gets a new mix of DNA from two parents, as well as any copying changes.
Step 3. Compare. Mixing two sets of DNA gives far more differences.
Answer: the sisters differ more; the yeast varies only through copying changes, the sisters also through the mixing of two parents' DNA.
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