Summary
Summary OCR A/AS-Level Biology 3.3.6 Adaptations of Plants to the Availability of Water
Revision summary of key knowledge from OCR A/AS-Level Biology 3.3.6 Adaptations of Plants to the Availability of Water.
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
Content preview
Adaptations of Plants tothe Availability of Water
Xerophytes
Adapted to survive in arid conditions
Waxy cuticle on leaf to reduce water lost by evaporation
Stomata on underside of leaf to reduce evaporation from direct sunlight
Stomata close at night to reduce water loss when the plant isn’t photosynthesising
Stomata close when water availability is low
Very widespread or deep roots
Low water potential inside leaves to reduce water loss – achieved by maintaining a high
salt concentration
Marram Grass:
o Rolling or curling or folding of leaves to trap air inside, preventing water loss due
to osmosis (maintains a high water potential outside leaf)
o Dense spongy mesophyll with few air spaces reducing area for evaporation
Cacti:
o Succulents – store water in their stem which becomes swollen – stems are ribbed
or fluted to allow for expansion when water is available
o Leaves reduced to spines to reduce area for evaporation and transpiration
o Stem can photosynthesise
Hydrophytes
Adapted to survive in wet conditions
Do not need to worry about water loss since water is abundant
Large air-spaces in leaves and stem keep the leaves buoyant to allow them to
photosynthesise
Stomata are on the upper side of leaves, so they are exposed to the air to allow gaseous
exchange
Specialised structures at the tip of leaves called hydathodes to release water droplets
which can evaporate since the climate is too humid for transpiration to occur
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 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 £2.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
66579 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now