Theory

CH3 - ENZYMES

(a) With reference to Fig. 4.1,(i) nameprocess A ..............................................................molecule B ...............................

2009 Summer

MCQ

CH3 - ENZYMES

In an experiment, 5 cm^3 of 1\% salivary amylase are added to 100 cm^3 of different concentrations of starch. Which graph shows the results of plotti...

2009 Winter

MCQ

CH3 - ENZYMES

The diagram shows a red blood cell and the concentrations of ions, in mmol dm-3, in the plasma and in the cell.Which ions are actively transported int...

2009 Winter

MCQ

CH3 - ENZYMES

Diagrams 1 and 2 show how the transverse section through a leaf changes when moved from one solution W to a different solution Y. How has the water...

2009 Winter

MCQ

CH3 - ENZYMES

Cystic fibrosis is a disease where $\text{Cl}^-$ ions are unable to be transported into cells.Which structure in the cell surface membrane is faulty?

2009 Winter

Theory

CH3 - ENZYMES

Amylase is an enzyme that catalyses the hydrolysis of starch. A student investigated the effect of pH on the activity of the enzyme.Eight test-tubes w...

2009 Winter

Theory

CH3 - ENZYMES

Sucrase is the enzyme that catalyses the hydrolysis of sucrose. A student investigated the effect of substrate concentration on the activity of this e...

2009 Winter

Theory

CH3 - ENZYMES

Proteases that work in alkaline conditions are made in large quantities for use in the detergent industry. The microorganism that is generally used fo...

2009 Winter

Theory

CH3 - ENZYMES

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

2010 Summer

Theory

CH3 - ENZYMES

(a) Some bacteria, such as Rhizobium, carry out nitrogen fixation, which is an important process in the nitrogen cycle. Explain what is meant by the ...

2010 Summer

Theory

CH9 - GAS EXCHANGE AND SMOKING

(a) Fig. 1.1 is an image of a transverse section through the trachea of the gas exchange system.Write the names of structures X and Y on Fig. 1.1 in t...

2021 Spring

Theory

CH2 - BIOLOGICAL MOLECULES

Starch molecules are the main storage molecules in many types of cereal grain, such as the grainof the barley plant.(a) When the seed inside a barley ...

2021 Spring

Theory

CH11 - IMMUNITY

T-helper lymphocytes and Leydig cells are two types of mammalian cells. The main role of T-helper lymphocytes and Leydig cells is to synthesise and se...

2021 Spring

Theory

CH8 - TRANSPORT IN MAMMALS

(a) Using a light microscope at a magnification of ×400, it is possible to identify different types of blood cell in prepared slides of mammalian blo...

2021 Spring

Theory

CH5 - THE MITOTIC CELL CYCLE

Each meristem cell in a leaf bud is able to grow and divide by mitosis to produce two daughter cells that are genetically identical to each other and ...

2021 Spring

Theory

CH10 - INFECTIOUS DISEASE

In March 2019, a tropical cyclone in the south-west Indian Ocean caused widespread flooding in a number of countries.The flooding and the damage cause...

2021 Spring

Theory

CH17 - SELECTION AND EVOLUTION

(a) The European eel, Anguilla anguilla, is a fish. The sizes of eel populations tend to remain relatively stable despite eels producing large numbers...

2021 Spring

Theory

CH18 - BIODIVERSITY, CLASSIFICATION AND CONSERVATION

(a) The grey wolf, *Canis lupus*, is a large predator. During the 20th century, the grey wolf in south-west Europe was hunted almost to extinction.Fig...

2021 Spring

Theory

CH19 - GENETIC TECHNOLOGY

Vitamin A deficiency is a widespread public health problem.One source of vitamin A is carotene in the diet. Carotene can be converted to vitamin A in ...

2021 Spring

Theory

CH13 - PHOTOSYNTHESIS

Red algae are multicellular photosynthetic prototists that contain phycoerythrin. Phycoerythrin is a photosynthetic pigment.(a) Fig. 4.1 shows:• the...

2021 Spring