Theory

CH15 - CONTROL AND CO-ORDINATION

(a) The steroid hormones oestrogen and progesterone are secreted by the ovary. State precisely the sites of secretion of each. oestrogen ................

2009 Summer

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Fig. 4.1 shows a section through a maize fruit.Fig. 4.1(i) Name the parts labelled A to D.A .........................................................

2009 Summer

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Hormones are secreted by endocrine glands.Explain what is meant by the term _endocrine gland_........................................................

2009 Winter

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Describe a reflex arc and explain why such reflex arcs are important. [7](b) Describe the structure of a myelin sheath and explain its role in the...

2009 Winter

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Fig. 5.1 shows a section through part of a human testis.Fig. 5.1Name structures A and B.A ...........................................................

2009 Winter

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Describe how a nerve impulse crosses a cholinergic synapse. [9](b) Explain the roles of synapses in the nervous system. [6]

2009 Winter

Theory

CH15 - CONTROL AND CO-ORDINATION

Follicle stimulating hormone (FSH) and luteinising hormone (LH) both consist of two polypeptide chains, the α and β chains.• The α chains of FSH ...

2010 Summer

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Describe the structure of a myelinated sensory neurone. [7](b) Explain how an action potential is transmitted along a sensory neurone. [8][Total: ...

2010 Summer

Theory

CH15 - CONTROL AND CO-ORDINATION

Follicle stimulating hormone (FSH) and luteinising hormone (LH) both consist of two polypeptide chains, the \( \alpha \) and \( \beta \) chains.The \(...

2010 Summer

Theory

CH15 - CONTROL AND CO-ORDINATION

(a) Describe the structure of a myelinated sensory neurone. [7] (b) Explain how an action potential is transmitted along a sensory neurone. [8] [Total...

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