Explain why an extensive network of capillaries and ventilation of the lungs helps to maximise the effectiveness of gas exchange.

The capillaries deliver blood that has high carbon dioxide levels and low oxygen levels and take away blood that has high oxygen levels and low carbon dioxide levels. This means there is always a concentration gradient between the blood and the air in the lungs. Ventilation of the lungs replaces air with higher concentrations of carbon dioxide and lower concentration of oxygen with air that has a higher concentration of oxygen and lower concentration of carbon dioxide. These factors maintain a high concentration gradient between the body and air for the two gases.

AC
Answered by Annabel C. Biology tutor

6140 Views

See similar Biology GCSE tutors

Related Biology GCSE answers

All answers ▸

What is the difference between competitive and non-competitive inhibition


Using your knowledge of natural selection and speciation, suggest how new species can evolve from the same common ancestor.


Guard cells open and close stoma in different conditions. When light intensity is high, potassium ions move into guard cells. Describe how this movement of potassium ions causes the stoma to open.


What are the functions of the substances in the blood?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning