Describe the types of movement of substances across a partially permeable membrane

Facilitated diffusion - the movement of substances down a concentration gradient via a membrane protein.
Active transport - the movement of substances against a concentration gradient which requires energy/ATP using a carrier protein.
Osmosis - the movement of water down a water potential gradient.

RT
Answered by Rachael T. Biology tutor

3434 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

What is phagocytosis and what steps are involved?


Describe and explain how the secretion of ADH affects urine production in the kidneys (4 marks)


Cystic fibrosis is an autosomal recessive condition. In a population, 0.04% of individuals have the disease. Use the Hardy-Weinberg equation to calculate the number of carriers of cystic fibrosis.


What is the definition of a pathogen and give two examples. (3 marks)


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