Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Didn't know it?
click below
Knew it?
click below
Don't know
Remaining cards (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Biology- Exchange

Exchange and transport

What do cells need to take in? Substances like oxygen and glucose for aerobic respiration and other metabolic reactions.
What do organisms need to excrete? Waste products from reactions such as carbon dioxide and glucose
How easy the exchange of substances is, depends on the organisms.... Surface area to Volume ratio (SA:V)
SA:V Smaller animals have a larger SA:V Larger animals have a smaller SA:V V (cube) = LxWxH V ( sphere) = 4/3πr3 SA = area of all faces added together
Single celled organism Substances can diffuse directly into or out of the cell across the cell surface membrane. Diffusion rate is quick due to the small distance the substances have to travel.
Multi- cellular organism diffusion across outer membrane is too slow. Some cells are deep within the body so big distance to travel. Large animals have a low SA:V so difficult to exchange enough substances. MCO have a high metabolic rate so use oxygen and glucose fast
Exchange surfaces Have special features to improve their efficiency. Most have: Large surface area thin good blood supply good ventilation
Root Hair Cell - specialised exchange surface (large surface area) Cells on plant roots that grow into long 'hairs' which stick out into the soil. Each root is covered in millions of microscopic hairs. Gives roots a large surface area - helps to increase the rate of absorption of water (osmosis) and mineral ions (AT)
Alveoli - specialised exchange surface (thin) Made from a single layer of thin, flat cells (alveolar epithelium). 02 diffuses out of the alveolar space into the blood, C02 diffuses in opposite direction. Thin alveolar epithelium decreases distance 02 & C02 travel - increasing rate of diffusion
Alveoli - specialised exchange surface (blood and ventilation) Surrounded by large capillary network giving each alveolus its own blood supply. blood constantly takes 02 away and brings C02 . Lungs are well ventilated so air in each alveolus is constantly replaced. Maintain a concentration gradient between 02 & C02
Fish Gills - specialised exchange surfaces ( blood and ventilation) 02 & C02 constantly exchanged between blood and water. Contain a large network of capillaries - keeps them well supplied with blood. Well ventilated- water constantly passes over them. Maintain concentration gradient of 02 - increase diffusion rate
Lungs - exchange organs As you breath in air enters the trachea (splits in to two bronchi - one bronchus for each lung). Then branches off into smaller tubes (bronchioles) which end in alveoli where gases are exchanged. Ribcage, intercostal muscle and diaphragm all work together
Goblet cells - exchange system (line the airways) secrete mucus. Mucuc traps microorganisms and traps dust particles in the enhaled air. Stopping them reaching the alveoli.
Cilia - exchange system (surface of cells lining the airways) Move the mucus containing the trapped micro organisms and dust up and away from the alveoli towards the throat, where it is swallowed. preventing lung infections
Elastic Fibres - exchange system (in the walls of the trachea, bronchi, bronchioles and alveoli) help the process of breathing. Breathing out the lungs inflateand the elastic fibres are stretched . Breathing out, the fibres recoil helping to push air out
Smooth Muscle - exchange system (in the walls of the trachea , bronchi and bronchioles) Allows the diameter to be controlled. During exercise smooth muscle relaxes, making the tubes wider - less resistance to airflow and air can move in and out of the lungs more easily
Rings of Cartilage - exchange system (in the walls of the trachea and bronchi) Provide support. Strong but flexible - stops the trachea collapsing when you breathe in and the pressure drops
Trachea Large C-shaped cartilage smooth muscle elastic fibres goblet cells ciliated epithelium
Bronchi Smaller pieces of cartilage smooth muscle elastic fibres goblet cells ciliated epithelium
Larger Bronchiole Smooth muscle elastic fibres goblet cells ciliated epithelium
Smaller Bronchiole Smooth muscle Elastic fibres ciliated epithelium
Smallest Bronchiole Elastic Fibres
Alveoli Elastic Fibres
Ventilation Breathing in and out consists of: inspiration - breathing in expiration - breathing out it is controlled by movements of the diaphragm, internal and external muscles and the ribcage
Inspiration External intercostal and diaphragm muscles contract - ribcage moves up and out and the diaphragm flattens - increasing volume of thorax - lung pressure decreases. Causes air to flow to lungs. Active process - requires energy
Expiration External intercostal and diaphragm muscles relax - ribcage moves down and in, diaphragm becomes curved again. Thorax volume decreases - air pressure increases - air if forced out. Passive process - doesn't require energy.
Tidal Volume (TV) The volume of air in each breath - usually about 0.4dm3
Vital Capacity The maximum volume of air that can be breathed in or out
Breathing rate How many breaths are taken - usually in a minute
Oxygen consumption/ oxygen uptake The rate at an organism uses up oxygen
Spirometer A machine that can give readings of tidal volume, vital capacity, breathing rate and oxygen uptake
Why does the volume of gas in a spirometer in the chamber decrease over time? The air that is breathed out over time is a mixture of carbon dioxide and oxygen. CO2 is absorbed by the Soda Lime so there's only oxygen in the chamber which the subject inhales from. As this oxygen gets used up by respiration, the total volume decreases
What do fish use for a gas exchange? Counter- current system. Blood flows through the gill plates in one direction and water flows over in the other. Maintains a large concentration gradient between water and blood. Concentration of oxygen in water is always higher than in blood.
What adaptions do fish have to get enough oxygen from water? Gill made of lots of gill filaments (primary lamellae) - big surface area - gas exchange. Filaments- covered in gill plates (secondary lamellae) - increasing surface area. Gill supported by gill arch, contains blood capillaries (diffusion).
How are fish gills ventilated? Open mouth- lowers buccal cavity- volume increases, pressure decrease - water sucked into cavity. Closed mouth- buccal cavity raised- volume decreased pressure increased- water forced out across filaments Operculum covers gill, opens H2O leaves gills
Trachea (insects) Air moves into trachea through spiracles. O2 moves down CG towards cells.CO2 from cells move down CG towards spiracles to be released into atmosphere. Trachea branch of into tracheoles which have thin permeable walls containing fluid which O2 dissolves in
Created by: Mia:)



Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards