B2 Circulatory System - Blood (page 33) Flashcards
What is Blood?
Blood is a tissue. One of its jobs is to act as a huge transport system.
What are the four main things in blood?
1) Red Blood Cells - they carry oxygen
2) White Blood Cells - defend against infection
3) Platelets - Help blood clot
4) Plasma - a liquid that carries everything in blood.
What is the job of Red Blood Cells?
They carry oxygen from the lungs to all the cells in the body.
What shape are Red Blood Cells, and why?
Their shape is a biconcave disc - (like a doughnut), this gives a large surface area for absorbing oxygen.
Do Red blood cells have a nucleus and why?
No they dont. - this allows more room to carry oxygen.
Red Blood Cells contain a red pigment, what is this called?
(pigment means the natural colouring)
Haemoglobin.
In the lungs, haemoglobin binds to oxygen to become what?
oxyhaemoglobin.
In body tissues, what happens to haemoglobin?
the reverse happens (regarding the lungs), oxyhaemoblobin splits up into heamoglobin and oxygen, to release oxygen to the cells.
The more red blood cells you’ve got means what?
it means the more oxygen can get to your cell.
At high altitudes, there is less oxygen in the air. How would this affect people who live at high altitudes?
People who live in high altitude areas, produce more red blood cells to compensate, due to lack of oxygen in the air.
What is the job of White Blood Cells?
to defend against infection.
How can White Blood Cells defend against infection?
1) Some can change shape to gobble up unwelcome microorganisms (bacteria/viruses) in a process called phagocytosis.
2) Others produce antibodies to fight off microorganisms, as well as antitoxins to neutralise any toxins produced by the microorganisms
Do White Blood Cells have a nucleus?
yes.
What are Platelets job?
They help blood clot at the wound - to stop all your blood pouring out, and to stop microorganisms getting in (so basically platelets just float about waiting for accidents to happen).
What is Platelets?
they are small fragments of cells.
Do Platelets have a nucleus?
No.
What will happen if the body has a lack of platelets?
Lack of platelets can cause excessive bleeding and bruising.
What is Plasma?
It is the liquid that carries everything in the blood.
What colour is the plasma liquid?
It’s a pale straw-coloured (pale yellow) liquid that carries just about everything.
Name everything that the plasma carries?
1 Red and white blood cells and
Platelets
2 Nutrients, like glucose and amino acids (these are the soluable products of digestion which are absorbed from the gut and taken to the cells of the body)
3 Carbon dioxide from the organs to the lungs
4 Urea from the liver to the kidneys
5 Hormones
6 Proteins
7 Antibodies and Antitoxins produced by the white blood cells.
Blood tests can be used to diagnose loads of things not just disorders of the blood, why is this?
This is because the blood transports so many chemicals produced by so many organs, and it is easier to take a blood sample rather than I piece of muscle.
Describe the purpose of platelets in the blood?
They help the blood to clot at the wound
