1. Darwin and his evidence
Biology Revision – CHAPTER 7 – Variation and Evolution Part 1
Variation
Differences between individuals or species is called variation it can be caused by our development (environment) or genetics, some characteristics are controlled by both.
Complete the table below by giving examples of human characteristics controlled by these different factors.
Natural selection
The theory of natural selection was developed by the scientist Charles
…………………..
……………………. in a population gives some individuals an advantage and others
a disadvantage in surviving in their environment
The organisms that that have more advantageous characteristics are more
likely to ………………………. and ……………………..
The offspring of these advantageous individuals will inherit these
advantageous from their parents ……………………
Genetics
Environment
Both
Darwin and his evidence
What evidence did Darwin collect to develop his theory of natural selection?
Fossils
Fossil evidence
Why is the fossil record incomplete?
Using the diagram describe some the changes that have happened to the horse throughout its evolution
What are fossils?
Draw a series of annotated diagrams to show how fossils form

2. Antimicrobial resistance
Biology Revision – CHAPTER 7 – Variation and Evolution Part 2
Antimicrobial resistance
Using diagrams explain how bacteria such as MRSA have evolved a resistance to antibiotics
Genetic engineering
What is genetic engineering?
What are the advantages of genetically modified crops (GM Crops)?
What are the disadvantages of GM crops?
Selective breeding
What is selective breeding?
Evolutionary trees
Extinction
What does extinction mean?
What are some possible causes of extinction?
Explain how a meteorite caused the extinction of the dinosaurs
From the evolutionary tree diagram above which group is most closely related to:
Humans

3. Darwin and his evidence
Biology Revision – CHAPTER 7 – Variation and Evolution Part 1
Variation
Differences between individuals or species is called variation it can be caused by our development (environment) or genetics, some characteristics are controlled by both.
Complete the table below by giving examples of human characteristics controlled by these different factors.
Natural selection
The theory of natural selection was developed by the scientist Charles
…………………..
……………………. in a population gives some individuals an advantage and others
a disadvantage in surviving in their environment
The organisms that that have more advantageous characteristics are more
likely to ………………………. and ……………………..
The offspring of these advantageous individuals will inherit these
advantageous from their parents ……………………
Darwin
Variation
Genetics
Environment
Both
Blood group
Hair length
Height
survive
reproduce
Eye Colour
Language
Skin colour
Natural hair colour
Scars and tattoos
Body mass (weight)
genes
Darwin and his evidence
What evidence did Darwin collect to develop his theory of natural selection?
Fossils
Fossil evidence
Why is the fossil record incomplete?
Using the diagram describe some the changes that have happened to the horse throughout its evolution
What are fossils?
The mineralised remains of organisms hard parts that have been preserved from millions of years ago.
Erosion has destroyed fossils (particularly very old ones, soft bodied organisms completely decay and leave no trace.
Studied unique animals and plants of the Galapagos islands and South America.
Selective breeding of pigeons
Fossils
Draw a series of annotated diagrams to show how fossils form
Over time the horse has changed by:
Fewer toes
Larger body
Larger head + teeth
Longer legs

4. Antimicrobial resistance
Biology Revision – CHAPTER 7 – Variation and Evolution Part 2
Antimicrobial resistance
Using diagrams explain how bacteria such as MRSA have evolved a resistance to antibiotics
Genetic engineering
What is genetic engineering?
What are the advantages of genetically modified crops (GM Crops)?
What are the disadvantages of GM crops?
The transfer of genes from one organism to another.
Grow faster – more food produced
Pest resistant crops – less pesticides
Genes may be transferred to other species through cross pollination
Long-term impacts on health are not known
Selective breeding
What is selective breeding?
Evolutionary trees
Extinction
What does extinction mean?
What are some possible causes of extinction?
Explain how a meteorite caused the extinction of the dinosaurs
Individuals with desired characteristic are selected to breed.
Best offspring are selected and are bred with other good offspring.
Over many generations of selective breeding the whole population has the desired characteristics.
Complete loss of all members of a species
Meteorite impact
Volcanism
Climate change
New predators
New diseases
New competitors
Destruction of habitats
Pollution
From the evolutionary tree diagram above which group is most closely related to:
Humans
Meteorite sent dust into the atmosphere
Blocked out the sun and prevented photosynthesis
Plants died through lack of light
Herbivores then carnivores died through lack of food (collapse of the food chain)
Chimpanzees