Apologia General Science, Module 11, The Human Body: Fearfully and Wonderfully Made

►Videos and resources for M11

The structure of the human body is made up of three basic units:
the skeleton, the muscles, and the skin.

My favorite thing about this module, is that we got to make THIS!

Veggie Skeleton!  =)

I knew the skeletal system was coming up, and I had found a veggie skeleton on Pinterest, and he was just soooo cute, that I just had to have one for our science class, too.
He was delicious!
We had him at the end of class, but I just had to put him first on here.  =)

In bleach for a week

Do you know what makes your bones strong?  and flexible so they're not brittle?
Minerals in bones make your bones strong and hard.
Collegen in bones makes them flexible.  What?  You think your bones aren't flexible?
They are to some extent.  Without the calcium in them, they would be veerrry flexible.

Experiment 11.1, Minerals in Bone called for a clean, dried-overnight chicken bone to be placed in vinegar for a week.  I also found an experiment online that said to put a bone in bleach.
So we did one of each.

In vinegar for a week

The kids had to include in their lab reports their Procedure (what they did), their Observations (what the bones looked and felt like), and their Conclusion (what it all meant), explaining the importance of both collegen and minerals in bones.

It's pretty obvious which bone was left with minerals but no collegen, and therefore was brittle; and which had collegen, but little or no minerals, and is too flexible to be of any use for humans or animals.










We also learned more about the composition of bones, such as compact bone and spongy bone.
Spongy bone is just as hard as compact bone!  Spongy bone just has spaces in it (like a sponge).  These spaces are filled with bone marrow.  I bet you probably knew your bones are alive, but did you know that the bone marrow makes red blood cells?


Do you know the difference between tendons and ligaments?
Tendons are what connects your muscles to the bones.  When you exercise, the 

tendon pulls on the bone, making it grow stronger.
Ligaments are strips of tissue that hold bones together in a joint.  Your upper arm bone, the humerous, is held in the elbow joint by ligaments.
Your elbows and knees have hinge joints, which is pretty easy to understand.  A hinge joint has limited mobility compared to some other joints, but it is more stable that way.
A ball-and-socket joint, such as the shoulder or hip, has a lot of mobility, but is not as stable as a hinge joint.
The more mobility, the less stability.  The more stable, the less mobile.
Cartilage is between the bones so that they don't rub together.
Most joints are surrounded by a "bag" that holds synovial fluid.  It is slippery, like egg white, and keeps joints lubricated for ease of movement.


Skeletal muscles are voluntary and make the skeleton move; smooth muscles are involuntary and make up the muscles of your organs; and the cardiac muscle is also involuntary and is the muscle of your heart.

Other organisms don't all have muscles.  For example, plants don't have muscles.  (Betcha didn't know that! haha.)
But plants can move by tropisms.  I'm sure you've had a plant in a sunny window, and after a day or two, you may have had to turn it to keep the plant looking "balanced."
This is because plants want to grow toward light.  Growing toward light is called phototropism.
If a plant isn't growing toward the light, but turning like sunflowers that track the sun across the sky, this is called heliotropism.
Roots growing toward water is hydrotropism.
Here is a picture of a bean plant that the older kids were experimenting with last year in Biology.
If I remember correctly, it only took a few hours for this plant to go from straight out to curved over the rim and back towards the window!

Heliotropism - movement toward the sun

We learned about the layers of our skin: epidermis, dermis, and hypodermis, and a few things about each layer.
Our hair and nails are also a part of this organ.
Our hair, nails, and the outer layer of skin are formed by keratinization, which is a process that kills the cell, but leaves it quite sturdy and hard to destroy.
Your outer layer of skin, the epidermis, is made up of dead skin cells and living cells. These living cells move upwards toward the outer layer and eventually fall off and are replaced with new keratinized cells.
The hair follicles  on your head are active for months at a time and have short periods of "rest" and can grow very long, unlike eyelashes or eyebrows.
Each hair is connected to a small, smooth (involuntary) muscle in the dermis.  When you get cold or nervous, this muscle contracts, pulling the hair straight up.  This is how you get goose bumps and your hair "stands on end."  This increases the amount of warm air trapped next to the body.

There are good bacteria living on our skin, and perspiration feeds this bacteria!  This beneficial bacteria produce lactic acid which is a good defense against many types of pathogenic (disease-causing) bacteria and fungi.
►When two or more different organisms benefit from each other, this is called symbiosis.
The older kids learned a lot about it last year in Biology, and this happens in many instances in Creation!  I just don't see how, with all the marvelous things that work together (every time), that anyone can believe it happened by chance!


sMiLeS,