🧬 DNA & Genetics
What molecule contains the genetic instructions for living things?
DNA
What is evolution?
Change in the characteristics of a population over generations
What type of evidence comes from preserved remains of ancient organisms?
Fossil evidence
What does the word "megafauna" mean?
Large animals, especially those much larger than their modern relatives
What is artificial selection?
When humans choose organisms with desirable traits to breed
What shape is DNA commonly described as having?
A double helix
What scientist is strongly associated with the theory of evolution by natural selection?
Charles Darwin
What can comparing DNA between species tell scientists?
How closely related the species are
Name one famous Australian megafaunal animal.
Diprotodon
Give one example of artificial selection.
Breeding dogs for particular traits
What are the four bases found in DNA?
Adenine, thymine, cytosine and guanine
What is natural selection?
When organisms with helpful inherited characteristics are more likely to survive and reproduce
What are homologous structures?
Structures with similar underlying features because of common ancestry
What is a fossil?
The preserved remains or traces of an ancient organism
How is artificial selection different from natural selection?
Humans choose which organisms reproduce in artificial selection, while the environment drives natural selection
What is a gene?
A section of DNA that contains instructions for a particular characteristic or function
Why is variation important for evolution?
It gives natural selection differences to act on
How can fossils provide evidence for evolution?
They show organisms from the past and changes in organisms over time
Give one possible reason why Australia's megafauna became extinct.
Climate change, environmental change, human activity, or a combination of factors
Why do farmers use selective breeding?
To produce useful characteristics such as higher milk production, faster growth or disease resistance
What is a chromosome?
A long, organised structure of DNA containing many genes
What can happen to a population when environmental conditions change?
Individuals with traits better suited to the new conditions may survive and reproduce more successfully
Why is evidence from fossils, DNA and anatomy stronger when they agree with each other?
Because multiple independent lines of evidence support the same evolutionary explanation
Why can it be difficult to determine exactly why Australia's megafauna became extinct?
Because several factors may have happened at the same time and the evidence is incomplete
What is one possible disadvantage of selective breeding?
It can reduce genetic variation and increase the chance of inherited problems