Showing posts with label Human Body. Show all posts
Showing posts with label Human Body. Show all posts

Tuesday, November 24, 2020

Basophil


We just learned about the type of white blood cell called the Eosinophil.

Another type of white blood cell is the Basophil.

We've learned about 4 other types of white blood cells (WBC):
- lymphocytes - that help kill off bad diseases using T, B or NK cells.
- monocytes - that help fight off infections and clean up garbage in the body.
- neutrophils - most common WBC that is the first line of defense for fighting infections.
- eosinophils - that live in tissues and help fight off allergic responses

The Basophil is the 5th and last type of WBC.

This type of white blood cell is one of the things that makes your body react when it is allergic to something. So this could be swelling up or getting itchy spots on your body.
It does this by letting out something called "histamines".

The eosinophils puts out "antihistamines" so when your body is trying to calm down from being allergic to something, these antihistamines work against the histamines.

Basophils also let out a chemical called heparin, which keeps your blood a liquid.
When your blood dries up and turns to a clot it can cause problems, so the heparin makes sure it doesn't dry up.


(from: wikipedia - basophil)


Kid Facts - Blast from the past: Rod Cells

Tuesday, November 17, 2020

Eosinophil


We just learned about the Neutrophil.

Another type of white blood cell is the Eosinophil, pronounced like "ee-oh-sin-oh-fill".

We've learned about 3 other types of white blood cells (WBC):
- lymphocytes - that help kill off bad diseases using T, B or NK cells.
- monocytes - that help fight off infections and clean up garbage in the body.
- neutrophils - most common WBC that is the first line of defense for fighting infections.

Less than 3% of the WBCs in the body are eosinophils.
They help fight viruses, and they also help the body fight off allergic responses.

One big difference is that these eosinophils live in tissues, they are not floating around in the blood stream.
They hang out in places like the intestines and spleen, but they do not go into the lungs, skin or esophagus.


(from: wikipedia - eosinophil)


Kid Facts - Blast from the past: Zonule of Zinn

Tuesday, November 10, 2020

Neutrophil


We just learned about the Monocyte.

Another type of white blood cell is a Neutrophil, also called a neutrocyte or heterophil.

We've learned about 2 other types of white blood cells:
- lymphocytes - that help kill off bad diseases using T, B or NK cells.
- monocytes - that help fight off infections and clean up garbage in the body.

The neutrophils are a lot like the monocytes, where their job is to go fight off bad germs and dirt that cause infections and make you sick.
These are the first line of defense for your body when there is an infection, they are like the emergency workers that rush to the scene to help out.


There are more neutrophils than any other type of white blood cell, and the human body makes about 100 billion neutrophils every day.

One of the only differences between monoctyes and neutrophils is that when a monocyte fights off an infection or disease they leave behind some clues about what kind of disease it might be.
These clues help the super powerful lymphocytes come in if there is a bad disease that needs to be killed off.


(from: wikipedia - neutrophil)


Kid Facts - Blast from the past: Uvea

Tuesday, November 3, 2020

Monocyte


We just learned about the kind of white blood cell called a lymphocyte, and the kind of lymphocyte called the B Cell.

There are other kinds of white blood cells, like one called the Monocyte.

These white blood cells are bigger than their cousins the lymphocytes, and their job is to go around cleaning up dirty things like infections in the body.

When they see something like dirt or infection they turn into something else called a macrophage and they wrap themselves around the bad stuff, almost like they are eating it, and they destroy the unhealthy bad stuff.

They are different from the lymphocytes because lymphocytes are really for targeting specific diseases or viruses, and monocytes are really more like cleaning up all the dirty garbage and fighting off infections.

So if your skin gets cut and you don't wash it off and keep it clean, you can get dirt and germs in your body.
The monocytes help fight off the bad stuff that comes from the dirt and germs if it gets infected.


(from: wikipedia - monocyte)


Kid Facts - Blast from the past: Choroid

Tuesday, October 27, 2020

B Cells


We've learned about just learned about the T Cells.

Another type of white blood cell lymphocyte is B Cells.

We are looking at:
- the type of blood cells called white blood cells,
- the type of white blood cells called lymphocytes
- the type of lymphocytes called B Cells.

Remember that we already learned about 2 other types of lymphocytes called NK Cells and T Cells.

In your body you have the living cells that make up your body or even bad diseases, and then you have a lot of other liquid floating around that is not made up of cells, just liquid.

The T Cells and NK Cells work on looking at the cells, killing bad ones and letting good ones live.

The B Cells work on the liquid that is flowing around the cells in your body.
If they find anything that looks bad, they let out these things called antibodies that stick to the bad disease and tell the body that this bad cell needs to be killed.


(from: wikipedia - b cell)


Kid Facts - Blast from the past: Ciliary Body

Tuesday, October 20, 2020

T Cells


We just learned about NK Cells.

Another type of lymphocyte is T Cells.

We are looking at:
- the type of blood cells called white blood cells,
- the type of white blood cells called lymphocytes
- the type of lymphocytes called T Cells.

These cells are called T Cells because they are usually found in a part of the body called the thymus, which is right in the middle of your chest behind your sternum.

All white blood cells are made in the bone marrow, but after these T Cells leave the bone marrow they go to the thymus.

T Cells are kind of like NK Cells as they go kill bad viruses that attack your body, but the T Cells are special because they are made to only attack certain types of viruses, where as the NK Cells attack everything.

When the T Cells go to the thymus, the thymus sorts them out and figures out which ones are set up to fight the right kinds of viruses that the body wants to fight, and then if a T Cell is not needed it is thrown away.

The T Cells are sort of like specialized attack soldiers waiting for certain viruses to show up and then they attack.


(from: wikipedia - t cell)


Kid Facts - Blast from the past: Fibrous Tunic

Tuesday, October 13, 2020

NK Cells


We just learned about the type of white blood cell called a Lymphocyte.

There are a few types of lymphocytes, like the NK Cells, also called Natural Killer Cells or large granular lymphocytes (LGL).

These cells float around in the body, and if they find a cell that doesn't look like it's supposed to be part of the body then it lets out some chemicals called cytokines that will destroy the bad cell.

The bad cells might be like a tumor, an infection or a virus, and when the NK Cell releases it's cytokins and the bad cell will be destroyed.
Because these LGLs kill other bad cells they are called natural killers.


(from: wikipedia - natural killer cell)


Kid Facts - Blast from the past: Aqueous Humour

Tuesday, October 6, 2020

Lymphocyte


We just learned that there are three types of blood cells, white blood cells, red blood cells and platelets.

Let's learn a little more about the white blood cells.
There are 5 different types of white blood cells!

One of the types of white blood cells is called a Lymphocyte.

Remember we learned that lymph is a white liquid carried in the lymph capillaries and then the lymphatic vessels, and the lymph nodes help clean out all the bad stuff in the lymph.

Lymphocytes are types of white blood cells that help fight off bad diseases, and in the white lymph liquid there is more of this type of cell than any of the other ones.

There are 3 different types of lymphocytes: T cells, B cells and NK (natural killer) cells and they each have a different job to help fight the bad diseases that attack the body.


(from: wikipedia - lymphocyte)


Kid Facts - Blast from the past: Vitreous Body

Tuesday, September 29, 2020

Platelet


We just learned about the Red Blood Cell and the White Blood Cell.

The third type of blood cell is the Platelet, also called thrombocytes.

The name thrombocyte comes from the Greek words θρόμβος (thrombos) which means clot, and κύτος (kytos) which means cell.
Platelets get carried around in the veins and arteries, and if they see that there is some damage to the body, like a hole in the vein or artery then they will try and patch up the hole.

A bunch of platelets will work to connect to each other, and when they work to block up a hole like this it is called a clot.

So when you have a cut and are bleeding, the platelets come and make a blood clot and help fix up the cut.


(from: wikipedia - platelet)


Kid Facts - Blast from the past: Macula

Tuesday, September 22, 2020

Red Blood Cell


We just learned about the White Blood Cell.

Another type of blood cell is the Red Blood Cell, also called RBC, red cell, red blood corpuscle, haematid, erythroid cell, or erythrocyte.

Most of the weird science names come from other languages, like corpuscle comes from the Latin word "corpus" for body, haematid comes from the Greek word "hema" for blood, and erythrocyte comes from the Greek words "erythros" for red plus "kytos" for hollow vessel.

Remember there are three types of blood cells: White Blood Cells, Red Blood Cells, Platelets.

There are more red blood cells than the other two type of blood cells, with TRILLIONS of RBCs in the body.

The job of these blood cells is to take oxygen from the lungs to the body, going along the veins and arteries of the circulatory system.

They are shaped a little like a frisbee or a bowl, and they don't have a middle part called a nucleus like most other cells.
Just like the white blood cells, these are made in the bone marrow, and a grown up person makes over 2 million of these RBCs per second!
They go around the body and do their job for about 4 months, and then they get recycled back into the body and replaced by new ones.


(from: wikipedia - red blood cell)


Kid Facts - Blast from the past: Sclera

Tuesday, September 15, 2020

White Blood Cell


We just learned that there are three types of Blood Cell red blood cells, white blood cells and platelets.

Let's learn a little about White Blood Cells, also called WBCs, leukocytes or leucocytes.

These cells in the blood help fight against diseases or other bad things in the body.
This could be a type of virus or some kind of germs that got into the blood.

White blood cells are made in the bone marrow.
If there are a lot of white blood cells in the body, this can be a way for doctors to tell if someone is sick.
Looking at a liter of blood, if there are between 4,000 and 11,000 white blood cells then this is ok.
If there is a lot more or a lot less, then it is a sign the person is sick.

There are a lot of different types of white blood cells and they all have different jobs for fighting off anything that might be trying to hurt your body.


(from: wikipedia - white blood cell)


Kid Facts - Blast from the past: Optic Nerve

Tuesday, September 8, 2020

Blood Cell


We just learned about the Haematopoiesis.

The bone marrow that uses haematopoiesis makes Blood Cells, also called hematopoietic cells, hemocytes or hematocytes.

Remember we learned before that the Greek word for blood is hema, so that is why all of those other names start with hema.

Blood cells come in three types: Red blood cells, white blood cells and platelets.


(from: wikipedia - blood cell)


Kid Facts - Blast from the past: Lens

Tuesday, September 1, 2020

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

Tuesday, August 25, 2020

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

Tuesday, August 18, 2020

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

Tuesday, August 11, 2020

Lymphatic Vessel


We just learned about the Lymph Capillaries.

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

Tuesday, August 4, 2020

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

Tuesday, July 28, 2020

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

Tuesday, July 21, 2020

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

Tuesday, July 14, 2020

Presbyopia


We just learned about the Astigmatism.

Another kind of refractive error is Presbyopia.

This is something that usually happens to older people, when the lens of the eye gets harder.
When that happens the eye focuses light behind the retina instead of right on it.

If someone has this presbyopia, they usually can't read small printed words, and a lot of times they have to hold things away from them to see them better.



(from: wikipedia - presbyopia)


Kid Facts - Blast from the past: Parotid Gland