Apologia General Science, Module 10, Classifying Life

►Videos and resources for M10
To see more in depth about any of the 5 kingdoms, click the Biology tab on either blog.

5 kingdoms!
Some are easy, and the kids knew those right away - animal kingdom and plant kingdom.  And after they thought a bit, one boy remembered bacteria.  Yep, I told him, there is a kingdom for bacteria.  But I didn't tell them the scientific name yet.
There is also a kingdom for fungi.  It's scientific name is.... kingdom Fungi.  =D

But when the kids heard of kingdom Protista... they kinda got a glazed look in their eyes.  That blank look that homeschooling mamas know all too well.  =D
I had a couple of Apologia Biology books on hand so we could look through those for more pictures.
Kingdom Protista is made of two subkingdoms: algae (which is a familiar word) and protozoa.
I got the blank looks again.

But pictures help a lot, and they were familiar with the name amoeba (see images).  So that was a start to understanding that subkingdom protozoa is primarily unicellular (only one cell) organisms that live in water or at least in moist areas.
An amoeba moves by using its jelly-like cytoplasm to squish into one end of the cell, and draws up and re-extends itself forward.  Like a caterpillar, but not.  =)
Another protozoan is a paramecium (see images).  Its shape is somewhat like a moccasin, or this traffic island!

We see this "paramecium" on our way to piano lessons every week.  haha!

If you look closely, you can see the grass growing around it... just like the "hairs" on a paramecium that are called cilia.  The paramecium uses cilia to help it move.
(Hmmmm... wonder if the city would let me paint it like a paramecium???)  lol.
If you look at some of the images at the paramecium link above, you will see that a tiny paramecium, made of a single cell, has a lot going on inside it!  It has many tiny organs called organelles.  They each have a job to do.

We also talked about subkingdom algae, and that it is not a plant!  There are quite a few differences between algae and plants, and you can read a little about that on this printable reference chart I typed up.


Note: 4 of the 5 kingdoms have cells with organelles, and as such, their cells are called eukaryotic cells.
Their DNA is in an organelle called the nucleus.
All cells are either eukaryotic or prokaryotic.  All cells.
Some organisms are made of only one cell - the tiny ones that can only be seen with a microscope; and some are multi-cellular - all the living things you can see.
But all are either eukaryotic or prokaryotic.  Having organelles or not having them.
Bacteria do not have organelles.


The kingdom that is made up of bacteria is kingdom Monera.
This kingdom is the only one with prokaryotic cells.  There are no organelles.  The DNA is not in a nucleus (an organelle), but is visible throughout the cell.  (see images)
Most people think of bacteria as only pathogenic - causing disease.  And a lot of bacteria do cause disease, but some are helpful.
The good bacteria that is most commonly talked about in textbooks are the bacteria that is used to make penicillin, the bacteria that is used to make some cheeses, and the bacteria that lives in your large intestine and makes vitamin K.  Some good bacteria  in your large intestine actually keep pathogenic bacteria from growing and reproducing there!

Experiment 10.1, Factors that Affect Bacterial Growth said to dissolve a chicken bouillon cube in 1 and 1/3 cups of hot water.  Then divide this into 4 small glasses.  I told the students to bring glasses on which there were no designs, and something they could easily see through because they would need to look through them later.
They were to add 1 tsp. of salt to one glass, 1 tsp. vinegar to another, one was to go in the refrigerator, and one was to have nothing done to it.  It would be the Control.  Each glass was labeled.
Anything that is done differently than what is done to the control is called a variable.  Salt, vinegar, and cold were the variables.

Hypothesis

I had started my experiment 2½ days earlier so that they could see my results and make predictions for their lab report.
I showed them my 4 glasses (that were labeled on the underside so they couldn't see), and they made their hypotheses as to which one of theirs would have the most bacteria, the next most, all the way to the least, based on the amount of bacteria that they thought would contamine each glass.
I had removed the cold one from the fridge about an hour before they got to class so that they could not tell from condensation on the glass which one had been in the refrigerator.

I placed a biology book behind the glasses to help with the visibility comparison.

Chicken bouillon cube in water left out for 2½ days, uncovered.
Each glass has a different variable so it could be compared to the Control.

We also talked about kingdom Fungi.
"Wait!" you say.  "What about the results of the bacteria experiment?"
Oh, I shan't give that away -- you'll have to do it and see for yourself.  =D
Kingdom Fungi has both single-celled (unicellular) organisms, and multi-cellular organisms.  But all are eukaryotic, meaning they have organelles.
One example of a unicellular fungal organism is yeast.
Mushrooms and mold are examples of multi-cellular fungi.
Fungi are not plants.  They are in a separate kingdom from plants because their cellular structure is so different, and because they do not make their own food as plants do.  (see reference chart)
Fungi feed on other dead organisms, such as decaying animals or dead leaves.  Fungi are helpful in this way because they are decomposers.  They decompose dead organisms.



Being a part of kingdom Fungi, yeast is also a decomposer.
Experiment 10.2 called for yeast to be put on a slice of banana.
← This is after 2 days, and nothing has really happened.  I'm assuming the yeast is supposed to do something significant, but so far, only the other slice has changed any that we can see.
It takes about a week to see results.  You should try it yourself and see what happens.  =)






Kingdom Plantae is self-explanatory.  In kingdom Plantae, there are.... PLANTS!
"Wow," I can hear you saying.  "I never knew!"  =D
Nearly all plants are multi-cellular, and actually, I don't know which ones aren't.  Just that nearly all are.  =)  I've never come across a plant that was so small I couldn't see it, hee hee.  =D
Plant cells have three things that pertain specifically to plant cells.  They are a cell wall, a large central vacuole, and chloroplasts. 
►See image (source)
The plant-like cells of algae have only one of these - chloroplasts.

When your plants wilt, they need water.  When plants don't have enough water, the large central vacuole in each of the plant's cells is depleted, making the plant limp.
After you water the plant, the water is taken up through tubes called xylem.  (This is caused by water evaporating from the leaves, causing suction.  Sort of.  Here's the technical explanation.)
As the water vacuoles fill, they press against the cell walls, making the plant become more rigid.
This rigidness is known as turgor pressure.

Turgor Pressure is sooo gone!

 Experiment 10.4, Turgor Pressure calls for limp celery.  So I let some sit in the sun for an hour.
←Is this limp enough?  =D
Ha, the celery isn't even touching the bottom of the glass, because it kept falling in.  So I just put it hanging over the side.

We placed our celery in water with blue food coloring, and we were to wait overnight.

Yep, this is the same celery!  Turgor Pressure!

After 24 hours, my celery still wasn't crip-looking, so I left it another day.  It looked much better by then, and I could clearly see the blue food coloring that had traveled up the xylem to the leaves.  ↓

After water and minerals make their way to the leaves, photosynthesis is carried out in the leaf.  After the food for the plant is made (called glucose), it will travel out of the leaf through tubes called phloem (flow'-em) to all parts of the plant for nourishment.
Just remember, up the xylem, down the phloem.



And last, we have kingdom Animalia.
Most likely the most familiar of all kingdoms, this one includes us!
No, we are not animals, but we have animal cells.
We most certainly do not have plant cells; we are not algae or protozoa; we're not bacteria, nor are we fungi.
We have animal cells, so we are placed in that kingdom.
But we look nothing like animals.  However, many of them do not resemble each other either!
Fish, butterflies, chipmunks, alligators, elephants, octopuses, birds, turtles, lions, tigers, bears, oh my! 

Butterfly on my son's finger

Just look at this awesome animal cell.
See the many organelles?
In the center is the nucleus. And in that nucleus is DNA.  Each strand of DNA is twisted up into an X or Y shaped chromosome.
►See image of tightly coiled DNA (source)
Humans have 46 chromosomes in each cell.  (So 23 pairs - XX or XY)
Each of these DNA strands, if unwound, can be about 6 feet long!
That's a lot going on in the nucleus of a cell.
But wait.  There are about a hundred trillion cells in your body!
Not all cells are the same shape and size, but about 2,000 average-sized cells can fit in a line across your fingernail.
Oh. my. word.
That is just so incredible!

But wait.  Think of this.
If we, and all animals, have animal cells... what makes us different?
Well, for starters, humans have 46 chromosomes in each cell.
An onion has 16 chromosomes in each cell, a horse has 64, and a carp has 104.
So how do humans, who all have 46 chromosomes, all look different from one another?
Think of it like the alphabet.  How many words can be made from the alphabet?  And how many sentences, and how many books...
Instead of letters, there are nucleotides (also referred to as nitrogen bases, or simply bases) in our 6-foot-long strands of DNA, and the nucleotides are in pairs.  Adenine with thymine, and cytosine with guanine.
And in the sequences (order, pattern) of nucleotides on our strands of  DNA, is the information that makes up who we are.
Except for identical twins, everyone's sequences are different from anyone else.
Fantastic!

How can anyone think that evolution did this?  Ever since I started really getting into science a couple of years ago, I have just been continually amazed at the complexity of God's creation!  As I study through a module, I discover how intricate His creation is, and yet each new module brings more discoveries to amaze me yet again. 

sMiLeS,