Haematopoiesis

We just learned about the Bone Marrow.

The bone marrow that makes blood cells is part of Haematopoiesis which comes from the Greek words αἷμα (aima) "blood" and ποιεῖν (poieín) "to make", so it means "to make blood".

A normal human body can make from one hundred billion to a trillion blood cells every day!


(from: wikipedia - haematopoiesis)


Kid Facts - Blast from the past: Retina

Bone Marrow

We just learned about the Lymph Nodes.

Another part of the lymphatic system is Bone Marrow.

When we think about our bones, we think of them as hard solid.
But inside our bones is something called bone marrow.

This bone marrow is soft, and is mostly white with some yellow and red.

When we think about blood, we just think of it red liquid, but there are really two types of blood cells called red and white blood cells.
Marrow is where these blood cells in the body are made, and even though we think of the outside of our bones as solid there are really small arteries and veins there that bring the fresh blood cells out of the bone marrow to go to the rest of the body.


(from: wikipedia - bone marrow)


Kid Facts - Blast from the past: Cornea

Lymph Nodes

We just learned about the Lymphatic Vessel.

Another part of the lymphatic system is the Lymph Node.

So we know that lymph is carried in the lymph capillaries and then the lymphatic vessels.
The lymphatic vessels bring the lymph to the Lymph Node.

This is a kidney bean shaped small part of the body that helps filter out bad stuff in the lymph.
It keeps the bad stuff in the lymph node and lets the other liquid lymph go back out to circulate.

The lymph nodes try to fight off the bad stuff collected inside them, and if there is too much bad stuff collected, then your lymph nodes can fill up and get swollen.

Sometimes if you are sick, you can feel on the side of your neck and feel a little lymph node bump sticking out.
Doctors can feel that area and if your lymph nodes are swollen that is a sign you are probably sick and they can do some other tests to try and figure out what sickness you have.

An adult has about 450 lymph nodes in their body, so the lymph gets carried all over and collected in these lymph nodes.


(from: wikipedia - lymph node)


Kid Facts - Blast from the past: Eye Color

Lymphatic Vessel

We just learned about the Lymph Capillary.

Another part of the lymphatic system is the Lymphatic Vessel.

These are like the veins and arteries in the body, but they carry lymph around the body.

The lymph is either brough to something called a lymph node, lymph duct or to a blood vein.

There are two types of lymphatic vessles:
- afferent lymph vessels: Bring lymph to a lymph node
- efferent lymph vessels: Bring lymph away from a lymph node


(from: wikipedia - lymphatic vessel)


Kid Facts - Blast from the past: Iris

Lymph Capillary

We just learned about Lymph.

Another part of the lymphatic system is the Lymph Capillary.

These are tiny little tubes a lot like the capillaries that carry blood, but they carry lymph instead, and they are a little smaller.

Remember that there are a bunch of left over liquids in the body that all make up what we call lymph.
The lymph gets sucked into these tiny capillaries that are all over the body.

These tiny tubes are like little collectors picking up all the lymph that gets left behind by the blood vessels or other organs, to carry it along the lymphatic system.


(from: wikipedia - lymph capillary)


Kid Facts - Blast from the past: Pupil

Lymph

Let's learn more about the Lymphatic System.

One of the first things to learn about the lymphatic system is Lymph.

The word lymph comes from an ancient Roman goddess of water named Lympha.

Lymph is a liquid that is sent all around the body in little tubes, a lot like blood is carried all over the body.

Every time the heart pumps it pushes blood out to all the parts of the body, and then pulls it back to the heart to get more oxygen and nutrients.
When the blood is pulled back, it leaves behind a lot of things like proteins and other liquids that just float around in the body.

The digestive system also leaves some things like fatty white liquids and other things behind after digestion.

Lymph is all of these left over liquids that get sent back around the body through the lymphatic system.
It can be made of proteins, fats, bacteria or other liquids.


(from: wikipedia - lymph)


Kid Facts - Blast from the past: Eyes

Lymphatic System

We just learned about Presbyopia.

We've learned a whole lot about Eyes, from the Cornea, Pupil, Iris and Retina to the Rods, Cones and Fovea!

Let's move on now and learn about something else, called the Lymphatic System.

This is a part of the body that helps make new blood cells, and also helps fight off diseases.
It's part of both the circulatory system and immune system, and goes through the whole body.

The lymphatic system isn't as well known as other parts of the body like the bones or muscles, but it was discovered over 300 years ago, so scientists have been studying it for a long time to figure out how the body works.


(from: wikipedia - lymphatic system)


Kid Facts - Blast from the past: Tonsils