Natural Selection, Adaptation & Population Change — Drills · Grade 7 Science
Chapter: Evolution, Evidence & Life HistoryWhat these drills covers
By the end of Natural Selection, Adaptation & Population Change you should be able to:
- I can explain natural selection, adaptation & population change.
- I can use evidence, a model, and stated assumptions to support a biological explanation.
4 questions, multiple choice, numeric and written answer, each with a worked explanation.
Vocabulary used: natural selection, adaptation, fitness, frequency, heritable variation.
Problem 1
Which is required in the stated selection explanation?
- Heritable variation and different reproductive success
- A wish to evolve
- Every individual identical
- No generation interval
Answer and explanation
Heritable variation and different reproductive success
Selection connects inherited differences with reproductive outcomes across generations.
Problem 2
A variant occurs in 18 of 60 organisms. Find its observed percentage.
Answer and explanation
30 %
18/60×100=30%.
Problem 3
Why must inherited variation be specified?
Answer and explanation
A temporary acquired difference may not be passed to offspring, so it cannot support the same across-generation mechanism.
Problem 4
Why use both variant count and total count?
Answer and explanation
The share depends on the denominator; raw counts alone may misrepresent frequency change.