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

CH7 - TRANSPORT IN PLANTS

(a) The structure of a phloem sieve tube element is adapted to its function.Each of explanations A to F describes how a particular structural feature ...

2020 Spring

Theory

CH3 - ENZYMES

Phosphatidate phosphatase (PAP) enzymes have an important role in lipid metabolism.The reaction catalysed by PAP is shown in Fig. 2.1.Experiments were...

2020 Spring

Theory

CH8 - TRANSPORT IN MAMMALS

During one cardiac cycle:blood enters the heart from the lungs and from the rest of the bodyblood leaves the heart to be transported to the lungs and ...

2020 Spring

Theory

CH9 - GAS EXCHANGE AND SMOKING

(a) When a section of lung tissue is viewed using a light microscope, it is possible to identify the trachea, the bronchus, the bronchioles and the al...

2020 Spring

Theory

CH11 - IMMUNITY

Myasthenia gravis and HIV/AIDS both involve disorders of the immune system.(a) Outline why myasthenia gravis is described as a disorder of the immune ...

2020 Spring

Theory

CH1 - CELL STRUCTURE

Fig. 6.1 is a transmission electron micrograph of a plant parenchyma cell.(a) The external environment of the parenchyma cell has a higher water poten...

2020 Spring

Theory

CH14 - HOMEOSTASIS

(a) Fig. 1.1 represents part of the wall of a proximal convoluted tubule (pct) in a kidney nephron.[Image_1: Fig. 1.1](i) Name the features of the wal...

2020 Spring

Theory

CH11 - IMMUNITY

Severe combined immunodeficiency (SCID) is a group of life-threatening diseases. SCID is caused by mutations that prevent the normal function of the i...

2020 Spring

Theory

CH16 - INHERITED CHANGE

Flowers of the common morning-glory plant, Ipomoea purpurea, can have several different phenotypes. An example of these flowers is shown in Fig. 3.1.[...

2020 Spring

Theory

CH16 - INHERITED CHANGE

The rainbow trout, Oncorhynchus mykiss, is a fish that is bred in commercial fish farms. Rainbow trout that have a blue-silver colour are sold at a hi...

2020 Spring