Summary
Summary AQA ALEVEL BIOLOGY NOTES ON FISH AND INSECT AND PLANT GAS EXCHANGE
- Institution
- AQA
ALEVEL NOTES ON GAS EXCHANGE - FISH AND INSECT AND PLANT GAS EXCHANGE ADJUSTED TO THE AQA SPECIFICATION AND MADE FROM MARKSCHEMES
[Show more]
Seller
Follow
Content preview
Gas ExchangeAn of its cells with like ( for
organism
needs to
supply every one substances
glucose and
oxygen
•
respiration )
The and metabolic of affect amount of material that For
size rate an
organism will the each is
exchanged
-
.
high larger surface
example ,
organisms with a metabolic rate exchange more materials and so
require a area
to volume ratio .
•
Different sized do this in different
organisms
:
ways
Features of specialised exchange surfaces
surfaces have effective of materials
Exchange the following characteristics to allow transfer
'
:
1- A surface
large area relative to the volume of the organism
2
Very thin so that the diffusion distance is short
3 to
Selectively permeable allow selected materials to cross
4 Movement of the medium diffusion
environmental to maintain a
gradient
5 A of medium like blood in to maintain
transport system to ensure the movement the internal order a
diffusion
gradient .
surface area ✗ difference in concentration
diffusion a
length of diffusion path
what surfaces ?
are
gas exchange
Gas surface between the environment of
exchange is
boundary outside environment and the internal
•
a
an
organism .
Gas Exchange in Single-celled Organisms 7¥
"÷: * .÷÷ ←.
Substances diffuse directly surface
into out of the cell surface membrane due to
high to volume
•
can or - area
ratio .
•
Diffusion rate is
quick because of the small distances the substances have to travel .
Adaptations
Relatively large surface
•
area
•
A thin surface
Short diffusion ( take biochemical diffuses the
pathway part in reactions it into
•
can soon as
oxygen as
cell )
Gas Exchange in Insects % spiracle
"" ÷⇐÷÷¥
tracheoles.ier.s.ia.in
. " " " " " "" "" """ "" " " " "" " "" " "" "" " "
" "
trachea
•
Tracheae divide into smaller dead-end tubes called
tracheoles
Gases enter and leave tracheae through called spiracles
tiny
'
pores
:
,
on the
body surface . Spiracles are opened and closed by a valve .
How in and out of the tracheal system
respiratory gases move
1- Tracheoles extend
body of the fluid-filled
throughout tissues insect
Oxygen is
brought
'
all the .
ends of
directly to the
respiring tissues ,
as there is a short diffusion pathway from a trachea / es
tracheae cell
any body
to .
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 talhaahmed360. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £7.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
76669 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