Top answers

How is heart rate controlled?

The heart muscle is myogenic , meaning that it is able to initiate its own contraction. The wall of the right atria has a region of specialised fibres known as the sinoatrial node (SAN). This node acts as th...
BM
Answered by Beth M. • Biology tutor
6018 Views

What is a pathogen and what role do they have in causing disease?

A pathogen is a harmful organism that causes infectious diseases. There are many types of pathogens: bacteria, fungi, viruses, protoctists, worms and insects. They allow diseases to be transmitted from perso...
MT
Answered by Molly T. • Biology tutor
3246 Views

Describe the flow of blood in the heart

Blood from the body enters the right atrium of the heart via the vena cava. It then travels into the right ventricle by a combination of gravity and contraction of the right atrium. After the right atrium ha...
ER
Answered by Emily R. • Biology tutor
3032 Views

What role do calcium ions play in contraction of the sarcomere? (4 marks)

When an action potential arrives at the motor end plate it causes depolarisation to occur in the sarcolemma of the effector muscle cells.2) Depolarisation spreads via T-tubules to the sarcoplasmic reticulum ...
BW
Answered by Ben W. • Biology tutor
7083 Views

how might a competitive inhibitor prevent the enzyme trypsin from working

inhibitor is a similar shape to the substrate this means the inhibitor blocks the active site of the enzyme the substrate cannot bind to the active site, so fewer enzyme substrate complexes can form
Answered by • Biology tutor
2557 Views