Search our library of Biology questions

Top answers

Biology

All levels

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

2714 Views

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

4501 Views

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

3339 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

11113 Views

Discuss the basis and variable outcomes of gene mutations

Mutations may be inherited or may arise sponataneously, resulting in distinct differences between individuals. Thus, given that genetic material is the single determinant of phenotypical characteristics, ...

Answered by Yousef M. • Biology tutor

2939 Views