Theory

CH12 - ENERGY AND RESPIRATION

(a) Table 4.1 shows a sequence of 12 nucleotides in the template strand of a short length of a DNA molecule, the corresponding primary transcript and ...

2024 Spring

3

Theory

CH12 - ENERGY AND RESPIRATION

(a) Aerobic respiration occurs in four successive stages: glycolysis (G), link reaction (LR), Krebs cycle (KC) and oxidative phosphorylation (OP).Comp...

2024 Winter

2

Theory

CH12 - ENERGY AND RESPIRATION

(a) Fig. 6.1 is a diagram of part of a mitochondrion.On Fig. 6.1, use arrows to show the route taken by oxygen from the cytoplasm into the mitochondri...

2024 Summer

2

Theory

CH12 - ENERGY AND RESPIRATION

A respirometer is a piece of apparatus that can be used to measure the rate of respiration of living tissue such as germinating peas.A simple respirom...

2024 Spring

2

Theory

CH12 - ENERGY AND RESPIRATION

(a) Aerobic respiration occurs in four successive stages: glycolysis (G), link reaction (LR), Krebs cycle (KC) and oxidative phosphorylation (OP).Comp...

2024 Winter

2

Theory

CH12 - ENERGY AND RESPIRATION

(a) Some organisms carry out respiration in anaerobic conditions when oxygen is not available or when there is a low concentration of oxygen. In yeast...

2023 Winter

3

Theory

CH12 - ENERGY AND RESPIRATION

(a) The respiratory quotient (RQ) values for different respiratory substrates can be calculated.Table 5.1 shows:• the formulae of four respiratory s...

2023 Winter

4

Theory

CH12 - ENERGY AND RESPIRATION

Many factors affect the rate of cellular respiration.(a) Pyruvate carboxylase (PC) deficiency is a rare disease. The rate of respiration in the cells ...

2023 Summer

1

Theory

CH12 - ENERGY AND RESPIRATION

(a) In plants such as rice, Oryza sativa, rubisco has a low rate of activity, which in turn affects the rate of photosynthesis. The cereal crop sorghu...

2023 Summer

1

Theory

CH12 - ENERGY AND RESPIRATION

(a) The Krebs cycle was named after the biochemist Sir Hans Krebs, who worked out the sequence in 1937.Fig. 1.1 is an outline of the Krebs cycle.Ident...

2023 Summer

2

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

3

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

3

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

3

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

3

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

3

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

3

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

3

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

3

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

2

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

3