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How does helicobacter pylori cause stomach ulcers?

It neutralises acid in the stomach and allows bacteria to damage the stomach epithelium.

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Before a drug is sold and released to the public, what measures must scientists take to ensure the safety of a drug and why are these steps taken?

Phase I- The drug must be tested on animals and tissue culturesPhase II - The drug is tested on healthy volunteers in small dosesPhases III- The drug is tested on sick patients in small dosesSmall doses a...

Answered by Saranya G. • Biology tutor

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How does oxidative phosphorylation produce ATP?

Oxidative phosphorylation requires the electron carrier system; comprised of four protein complexes (complexes I - IV) as well as the enzyme ATPase. These are intrinsic enzymes that line the inner mitocho...

Answered by Jack B. • Biology tutor

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What are the non-specific defence systems of the body against pathogens?

There are four main non-specific defence systems, all of which are immediate and the same for all pathogens (hence 'non-specific).1) skin: it acts as a primary defence mechanism as the dry, dead cells on ...

Answered by Sai Harshita V. • Biology tutor

3248 Views

People who have McArdie's disease produce less ATP than healthy people. As a result, they are not able to maintain strong muscle contraction during exercise. Use your knowledge of the sliding filament theory to suggest why (AQA BIOL5)

Idea ATP is needed for:1. Attachment / cross bridges between actin and myosin;2. Power stroke / movement of myosin heads in rowing action / pulling of actin towards the centre of the sarcomere;3. Detachme...

Answered by Salma O. • Biology tutor

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