Organ
Great question, Ima!
FeatureRed Blood Cells (RBCs) White Blood Cells (WBCs) Main jobCarry oxygenFight germs and infections Colour Red (contains hemoglobin) Colorless /whiteNumberVery manyMuch fewerShapeUsually round and disc-shapedDifferent shapes depending on typeNucleusNo nucleus in humansHave a nucleusLife spanAbout 120 daysDays to years, depending on the type
Red Blood Cells
Carry oxygen from the lungs to the body.
Carry some carbon dioxide back to the lungs.
Contain hemoglobin, which gives blood its red color.
White Blood Cells
Protect the body from bacteria, viruses, and other germs.
Are part of the immune system.
Help keep you healthy when you get sick.
Easy way to remember
Red blood cells = Oxygen carriers
White blood cells = Germ fighters
How do red blood cells cary oxygen
Red blood cells carry oxygen using a special protein called hemoglobin.
How it works?
In the lungs, oxygen enters the blood.
Oxygen attaches to hemoglobin inside red blood cells.
The heart pumps the blood around the body.
Oxygen is released to body cells, which use it for energy.
The bus (red blood cell) picks up passengers (oxygen) at the lungs.
It travels through blood vessels.
It drops off the passengers at body cells.
Why hemoglobin is important
Hemoglobin can hold oxygen and release it where it is needed. It also gives blood its red color.
A single red blood cell contains about 270 million hemoglobin molecules, allowing it to carry a lot of oxygen!
What is hemoglobin?
Hemoglobin is a special protein found inside red blood cells. It helps carry oxygen from the lungs to all parts of the body.
What does hemoglobin do?
Picks up oxygen in the lungs.
Carries oxygen through the blood.
Delivers oxygen to body cells so they can make energy.
What is it made of?
Hemoglobin contains:
Protein parts called himoglobin.
Iron atoms, which help bind oxygen.
The iron is one reason blood is red.
Fun fact
One hemoglobin molecule can carry up to 4 oxygen molecules at the same time!