Theory

CH17 - SELECTION AND EVOLUTION

Several different processes can affect allele frequencies in populations.(a) Outline the processes that may affect allele frequencies in wildlife popu...

2024 Winter

3

Theory

CH17 - SELECTION AND EVOLUTION

Variation exists in populations of a species and this may provide the opportunity for evolution to occur.(a) Phenotypic variation exists in many forms...

2024 Summer

3

Theory

CH17 - SELECTION AND EVOLUTION

Genes have a role in determining the overall phenotype of an organism.(a) Using haemophilia as an example, explain the relationship between a gene, a ...

2024 Summer

2

Theory

CH17 - SELECTION AND EVOLUTION

(a) Variation in a particular characteristic can be described as either discontinuous or continuous. Table 5.1 contains a list of statements that app...

2024 Winter

3

Theory

CH17 - SELECTION AND EVOLUTION

Complete the following paragraphs using the most appropriate word or words.The theory of evolution describes a process that can lead to the formation ...

2024 Spring

3

Theory

CH17 - SELECTION AND EVOLUTION

(a) Young spadefoot toads are called tadpoles and live in water in ponds.S. multiplicata tadpoles show three different phenotypes due to genetic varia...

2024 Winter

3

Theory

CH17 - SELECTION AND EVOLUTION

It has been hypothesised that the mutation rate of an animal species may affect how fast animals of that species age and how long they live (lifespan)...

2024 Summer

3

Theory

CH17 - SELECTION AND EVOLUTION

The harlequin ladybird, Harmonia axyridis, is an insect that shows discontinuous variation in colour pattern and continuous variation in body size.(a)...

2024 Summer

3

Theory

CH17 - SELECTION AND EVOLUTION

(a) Young spadefoot toads are called tadpoles and live in water in ponds.S. multiplicata tadpoles show three different phenotypes due to genetic varia...

2024 Winter

2

Theory

CH17 - SELECTION AND EVOLUTION

Oryza is a genus of grass plants that includes the rice, Oryza sativa, a food crop.(a) Farmers flood fields of rice because this encourages faster gro...

2023 Summer

3

Theory

CH2 - BIOLOGICAL MOLECULES

(a) Fig. 1.1 shows the breakdown of a molecule of sucrose.(i) Name the bond indicated by T...............................................................

2010 Summer

3

Theory

CH1 - CELL STRUCTURE

(a) Calculate the actual diameter of the alveolus along the line X–Y.Show your working and give your answer to the nearest micrometre.Answer = ........

2010 Summer

3

Theory

CH8 - TRANSPORT IN MAMMALS

(a) Fig. 3.1 shows a cross-section of the heart at the level of the valves.[Image_1: Fig. 3.1](i) Complete the following flow chart to show the pathwa...

2010 Summer

2

Theory

CH10 - INFECTIOUS DISEASE

Malaria and tuberculosis (TB) are two of the most important infectious diseases.(a) Define the term \textit{infectious disease}..........................

2010 Summer

3

Theory

CH6 - NUCLEIC ACIDS AND PROTEIN SYNTHESIS

(a) Name the stage during the mitotic cell cycle when replication of DNA occurs..........................................................................

2010 Summer

2

Theory

CH1 - CELL STRUCTURE

(a) Name the processes that occur at H, J and K.H .......................................................................................................

2010 Summer

3

Theory

CH1 - CELL STRUCTURE

(a) Explain how Fig. 1.1 can be identified as a plant cell...............................................................................................

2010 Summer

3

Theory

CH8 - TRANSPORT IN MAMMALS

Fig. 2.1 is a diagram of a vertical section through a healthy mammalian heart. (a) (i) Label the two chambers of the heart by writing in the boxes pro...

2010 Summer

2

Theory

CH10 - INFECTIOUS DISEASE

(a) Using the ‘without HIV/AIDS’ and ‘with HIV/AIDS’ data shown in Table 3.1, calculate the percentage decrease in life expectancy for Botswan...

2010 Summer

3

Theory

CH2 - BIOLOGICAL MOLECULES

Fig. 4.1 shows the primary structure of a lysozyme molecule, an enzyme found in tears, saliva and in lysosomes. (a) (i) Explain what is meant by th...

2010 Summer

3