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

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