1. 5 a day revision B5 – Plant development
Describe how to take a cutting.
What are auxins and what do they do?
What is phototropism?
Why might a plant breeder may take many cuttings from a particular plant?
You are provided with several plant shoots and a sample of auxin.
Describe an experiment that you could carry out to show that auxin causes a shoot to bend.

2. 5 a day revision B5 – DNA to protein
Where in the cell are proteins made?
How does the order of bases in a gene determine which protein is made?
Which DNA bases always pair together?
Why is a RNA copy of the DNA made before proteins are produced?
DNA is made up of four different bases, A T, C and G. In a DNA sample, 23% of the bases are T. Calculate the percentage of bases that are G.
Show your working!!

3. 5 a day revision B5 - Development
What name is given to the parts of plants where mitotically active cells are found?
How are embryonic stem cells different to adult cells?
In a human embryo, all the cells are unspecialised until what stage?
What is a zygote?
Explain how animals and plants different in terms of their capacity to grow.

4. 5 a day revision B5 – gene switching and stem cells
Myosin is a protein found in muscle cells. Why is it not found in other cell types?
Why can embryonic stem cells produce any type of cell?
What name is given to the process of stem cells becoming specialised?
Give an example of an application for embryonic stem cells.
Describe how cloning can be used to produce embryonic stem cells.

5. 5 a day revision B5 – cell division
Why are gametes produced by meiosis and not by mitosis?
The nucleus of a cell contains 2 pairs of chromosomes. Draw a diagram to show the daughter cells produced after mitosis.
What are the main processes in the cell cycle?
Give two differences between mitosis and meiosis.
Every nucleus in the body cell of an elephant contains 56 chromosomes. Read the statements about cell division and put a tick in the correct box for each statement.