Active Processes Across
Membranes
Active Transport
Movement of substances against their concentration gradient
Low to high concentration
Requires ATP because more energy is needed than passive processes, which use the
integral kinetic energy of molecules
Energy is provided y the hydrolysis of ATP
This energy is needed to allow the carrier protein to change its shape to carry ions to
the other side of the membrane
Carrier Proteins
Have specific sites which combine reversibly with certain solute molecules or ions
Also have specific regions which bind to, and allow the hydrolysis of, ATP to release
energy – through this they act as an enzyme by catalysing the hydrolysis reaction
Energy allows them to change their conformation (shape) and in doing so they carry the
ion from one side to the other
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller izzylewington04. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $3.89. You're not tied to anything after your purchase.