UNIT 2 - GCSE Biology Revision



UNIT 2

[pic]

Jan 2013 Higher B2

[pic]Jan 2013 B2 Higher

[pic]

June 2012 B2 Foundation

[pic]

Specimen B2 – 6 marks

[pic]

[pic]

June 2012 B2 Higher – 6 marks

[pic][pic]

B2 Higher June 2013

[pic]

B2 Long Answer Qs from e-AQA

Q1.          During evolution, many groups of animals have become extinct (died out).

a) The graph shows how the number of animal groups has changed over time.

[pic]

Harold L Levin, The Earth Through Time,© 2005,

Reprinted with permission of John Wiley & Sons, Inc.

How has the number of animal groups changed between 200 million years ago and the present day?

........................................................................................................................

........................................................................................................................

(1)

(b)     In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.

Describe the different causes of the extinction of organisms.

Your description should include possible reasons for the mass extinctions shown on the graph.

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

(6)

(Total 7 marks)

 

 

Q2.          Sometimes babies are born with extra fingers or toes as shown in the photograph.

This condition is called polydactyly.

[pic]

The diagram shows the inheritance of polydactyly in a family.

[pic]

(a)     Polydactyly is caused by a dominant allele, D.

The recessive allele of the gene is represented by d.

Use one genetic diagram to show the inheritance of the polydactyly gene by R and S.

 

 

 

 

 

 (4)

(b)     In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.

Embryos can be screened for genetic disorders.

Many people would favour the use of embryo screening for cystic fibrosis but not for polydactyly.

Compare the issues involved in the use of embryo screening for cystic fibrosis and for polydactyly.

You should use your knowledge and understanding of the process and the two conditions.

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

(6)

(Total 10 marks)

 

 

Q3.          Meiosis and mitosis are different types of division in human cells. Compare the two processes by referring to where each takes place and the kind of products that are made.

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

...............................................................................................................................................

(Total 6 marks)

 

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download