2. Transport Systems Flashcards
What are cells?
The building blocks of any living thing.
What are tissues?
Groups of cells with a similar structure and function
What are organs?
Different tissues working together
What are organ systems?
Groups of organs that perform a particular function
What are organisms?
A whole living thing
Why do large organisms need a transport system?
- absorb nutrients and respiratory gases and to remove excretory products
- transport materials between exchange surface and the cell
When is there a greater need for a specialised transport system?
When there is a lower SA/V ratio because the organism is more active
What are adaptations of red blood cells?
They have an unusual shape and are concave to give them an increased surface area
What is haemoglobin?
A large protein molecule folded around four iron atoms
Equation for oxyhemoglobin?
Haemoglobin + Oxygen = Oxyhemoglobin
What happens to haemoglobin in a high concentration of oxygen?
It reacts with the oxygen
What happens to oxyhaemoglobin in a low concentration of oxygen?
The oxyhemoglobin splits to form oxygen and haemoglobin and the oxygen diffuses to where it’s needed
What is plasma?
The clear liquid of blood that remains after red blood cells are removed
What does plasma contain?
Water, salts, antibodies and other proteins
What is plasma for?
It’s a transporting medium for cells and a variety of substances
What does plasma help carry out?
Blood clotting, fighting diseases
What do white blood cells do?
Engulf then digest pathogens
What are pathogens?
Microbes that cause disease
What can white blood cells produce?
Antibodies and antitoxins
What are platelets?
Small fragments of cell which are important in blood clotting
What direction do arteries carry blood?
Away from the heart
What direction do veins carry blood?
Towards the heart
Which has a pulse : arteries or veins?
Arteries
What do valves do?
Prevent the back flow of blood as it moves from the body to the heart