B2 Revision

B2 Revision

Today we will focus on three sections of revision: DNA and fossils.

Fossils

• A fossil is the preserved remains of a dead organism from millions of years ago. Fossils are found in rocks and can be formed from:

• hard body parts, such as bones and shells replaced by minerals

• preserved in amber, peat bogs

• footprints

• We can't be sure of how plants and animals looked using fossils because there were no human then.

Multiple Choice

How are fossils formed?

• Shells are replaced by minerals

• Randomly

Open Ended

How are fossils formed?

Multiple Choice

Why can we not be sure of how plants and animals looked using fossils?

• Because we don't know

• There were no humans living then

Open Ended

Why can we not be sure of how plants and animals looked using fossils?

Multiple Select

What two things causes organisms to become extinct?

• diseases

• fever

• lack (less) of food

Open Ended

How are fossils formed?

Open Ended

Why can we not be sure how plants and animals looked in the past based on fossils?

Open Ended

What things cause organisms to become extinct?

Evolution

• Charles Darwin proposed the theory of evolution.

• This theory said that organisms change over time and the best ones survive.

Biodiversity

• Biodiversity means the different types of plants and animals living in an area.

• We can increase biodiversity by planting more plants and letting animals live

Multiple Select

_________ __________ figured out the theory of evolution by natural selection.

• Carl Wose

• Robert Bunsen

• Charles Darwin

Multiple Choice

What is biodiversity

• The number of different plant and animal species in an area

• The types of different people

DNA and the Genome

- DNA is a double helix shape. It looks like a twisted ladder.

- The instructions in DNA code for amino acids .

- Amino acids join to make a protein

- A genome is all the different genes/DNA of an organism.

Multiple Choice

We are all different from each other. What is this called?

• Variation

• Genetic inheritance

Multiple Choice

Describe the structure of DNA

• Double helix

• Line

• Zig zag

Multiple Choice

A genome is.....

• All the genes of an organism

• inherited

Open Ended

Explain what happens in the reflex arc. You may use BBC Bitesize to help you.

Open Ended

Explain the steps you would take to measure reaction times.

Open Ended

How are fossils formed?