100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Summary Controlling Water potential. $10.45   Add to cart
Quickly navigate to
Preview
  2.  
  3. OCR
  4.  
  5. Biology A
  6.  
  7. Unit 5

Summary

Summary Controlling Water potential.
 6 views  0 purchase
  • Course
  • Unit 5
  • Institution
  • OCR

Revision notes on controlling water potential. A level biology OCR A revision notes. Notes on module 5: Communication, homeostasis and energy. Summary/ information you need to memorize for a level biology OCR A exams.

Preview 1 out of 2  pages

Document information

  • December 4, 2023
  • 2
  • 2022/2023
  • Summary

Subjects

  • water potential
  • homeostasis
  • control
  • osmosis
  • active transport
  • diffusion
  • solute
  • communication
  • energy
  • a level
  • biology
  • ocr a
  • revision notes
  • module 5

Written for

  • A/AS Level
  • OCR
  • Biology A
  • Unit 5
All documents for this subject (112)

Seller

avatar-seller
flcarr23

Content preview

Controlling Water Potential:


 Osmoregulation is the control of water & salt levels in the body.
 Water is gained through food, drink & metabolic products.
 Water is lost through urine, sweat, water vapour & faeces.

 Osmoreceptors in the hypothalamus monitor blood passing
through the hypothalamus – they are sensitive to water
potential.
 When the water potential in the blood is too low, water moves
out of these cells into the blood vessels by osmosis – causing
the osmoreceptor cells to shrink.
 This causes neurosecretory cells in the hypothalamus to be
stimulated to produce ADH.
 When the neurosecretory cells are stimulated, they cause ADH
to be released into the blood capillaries in the posterior
pituitary gland.


 ADH uses a secondary messenger system as it is too large &
polar, so cannot cross the plasma membrane since it is not lipid
soluble:
1. ADH molecules combine with receptors on the plasma
membrane on cells of the collecting duct.
2. This activates an enzyme, which in turn causes vesicles
within the cell to fuse with the cell surface membrane.
3. These vesicles contain aquaporins (water permeable
channels) making the collecting duct membrane more
permeable to water.
4. More water leaves the collecting ducts by osmosis & will
be reabsorbed into the blood, resulting in more
concentrated urine.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

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

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

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 flcarr23. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.45. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

64438 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$10.45
  • (0)
  Add to cart