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State the source, substrate, products and optimum pH of one amylase, one protease, and one lipase

Amylase (Salivary amylase) Source: salivary glands in the mouth Substrate: starch Products: maltose Optimum pH: 4.6-5.2 Protease (pepsin) Source: chief cells in the stomach Substrate: proteins, polypeptide c...
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Answered by Louise H. Biology tutor
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Explain the need for enzymes in digestion

Mechanical digestion breaks down large food particles into smaller ones, increasing the surface are to volume ratio. However, polymers present in food particles require a very long time to break down at body...
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Answered by Louise H. Biology tutor
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(a) State four functions of proteins, giving a named example of each.

Proteins can function as 1. Biological Catalysts: enzymes that decrease the activation energy of a reaction and facilitate the progression of chemical reactions 2. Hormones: proteins can function as hormones...
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Answered by Tatiana S. Biology tutor
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Explain how type 1 diabetes occurs

Type 1 diabetes occurs when the immune system to fails to identify a group of cells in the pancreas called the beta islet of Langerhans cells as 'self' cells. This means that they are recognised as 'foreign'...
ER
Answered by Emma R. Biology tutor
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Name two structural differences between arteries and veins.

Arteries have thick, elastic, muscular walls whereas veins have thin walls with few elastic fibres. Arteries need these properties to give them the strength and elasticity needed to cope with the high pressu...
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Answered by Jennifer W. Biology tutor
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