Asexual or sexual

The idea

Asexual reproduction produces individuals with only very minor differences, arising from small inaccuracies in DNA copying, whereas sexual reproduction generates even greater diversity.

Bacteria and people

One bacterium divides, and the two new bacteria divide again. That makes four bacteria. Now think of a group of human beings.

Which group shows more variation among its individuals?

• The group of human beings
• The four bacteria from one bacterium
• Both show the same amount

Sort the statements

Tap each statement, then tap the kind of reproduction it describes.

Minor or greater

When one individual reproduces, as one bacterium does by dividing, the new individuals are very similar. Small mistakes in copying DNA make small differences. With sexual reproduction, there is even greater diversity.

Asexual reproduction produces individuals with only very minor differences, arising from small inaccuracies in DNA copying, whereas sexual reproduction generates even greater diversity.

Notes

Asexual reproduction gives very minor differences (small DNA copying inaccuracies). Sexual reproduction generates even greater diversity.

Check yourself

The four bacteria made when one bacterium divides twice are…

Which kind of reproduction generates even greater diversity?

What causes the very minor differences in asexual reproduction?

• very different from each other, as in sexual reproduction. A single bacterium dividing is asexual reproduction, which gives only very minor differences.
• very similar, with very minor differences — correct. Yes!
• completely identical, with no differences at all. Small inaccuracies in DNA copying produce very minor differences.
• Asexual reproduction. Asexual reproduction produces individuals with only very minor differences.
• Both generate the same diversity. Sexual reproduction generates even greater diversity than asexual reproduction.
• Sexual reproduction — correct. Yes!
• Small inaccuracies in DNA copying — correct. Yes!
• The mixing of DNA from two parents. A single individual reproduces in asexual reproduction, so there is no second parent.
• Selection by environmental factors. Selection by the environment decides which variants survive. The small differences themselves arise from inaccuracies in DNA copying.