This topic builds on what we studied in B13 and B14 and looks at how the discovery of genes unlocked the mystery of inheritance. We will also look at how and why scientists classify animals and how this classification has had to change as new evidence is discovered.

Specification links:

• Set 1 all of 4.6.3 and 4.6.4

• Set 2 and 3 all of 4.6.3 and 4.6.4

Task 4b:

• Describe the stages of fossil formation

• Give the conditions needed for a fossil to form when an organism doesn’t decay

• List the reasons why there are gaps in the fossil record

• Explain why fossils are evidence for evolution

• Define extinction and list the causes (biotic and abiotic)

• Define mass extinction and give two ways it could be caused.

Task 4c: Answer the exam questions and self mark

Task 5b: Make notes that:

• Describe how antibiotic resistance occurs in bacteria

• List the ways we can try to prevent antibiotic resistance occurring

• Answer the questions on slide 13

• Describe the graph on the left

• Suggest explanations for the trends you described

Task 5c: Penicillin is an antibiotic which stops bacteria from reproducing. It was used a lot in the past to treat bacterial infections in humans and other animals. In many hospitals there are now strains of penicillin resistant bacteria.

Explain how natural selection could have produced these strains of penicillin resistant bacteria

Task 6b: Make notes that:

• Define classification and explain why it is important

• Give the order of classification that was proposed by Carl Linneaus

• Watch the video on slide 12 and answer the questions

• Define a species

• Name the 6 kingdoms

• Name the three domains proposed by Carl Woese and explain why classification was changed to the domain model

• Describe why evolutionary trees are useful

Task 6c: Answer the exam question and self mark

Task 8: Complete the quiz for your set to make sure you understand this unit.