Sunday, April 27, 2014

Biology 101, Chapter 7, The 6th Day – Biology History, Cells, Genetics [post 1/3]

I really wish we had more time to cover this chapter!  It is huge, with a lot of my favorite things! =)
So there are 3 blog posts total, since they kind of divided themselves up that way.  =)
And since the moms agreed we were too busy to fit in another class, I had the kids to go ahead and be studying up on some stuff during spring break.  They were thrilled, lol.  ; )
But I am adding stuff in, and we do take 4 weeks per chapter instead of 3, so that and the pre-studying will have to do.  =)
I'd advise 6 weeks if you have it.  ; )


Animal Cell Pizza!
The Secretion Vesicle looks like someone took a bite, lol! =)
Blog Posts for Chapter 7:
• Post 1/3 Cells
• Post 2/3 - DNA
• Post 3/3 - Genetics

In addition to Biology 101:
Fun Cell Activity (teacher cheat sheet included) 1 point for placement, 1 point for naming the organelle, 1 point for giving the function.
Games like this give a jump start and make studying easier when they get home.
Animal Cell Pizza and Plant Cell Cake - we will not be doing these this year, but here is the link.
• Google for more edible cell ideas.

Other Study Links
Animal Cell coloring page
Plant Cell coloring page
• Plant and Animal Cell Venn diagram (found here) - I made this blank one for our class.
Comparison of plant and animal cells.  Click on an organelle name to jump to its description.  Use your back arrow to jump back to the cell.
A green square      beside the name of an organelle's description means that the organelle is typically only found in plant cells.  A red square      indicates organelles that are typically in animal cells.
Interactive Cell - watch the motion of organelles in a cell.  Click the organelle labels to read the name of the organelle.  Read the description in the box on the side.
Not all organelles are pictured, but can you tell if this is a plant cell or an animal cell?  
•Interactive, animated tutorial w/ 6 questions at the end: From Cells to Systems.  Subtitles if needed.
• Really cool - Comparing Cell Size - use the slider below the pic to slowly zoom in.
• Read Potential Effects of Drinking Saltwater
• Another, super cute video about Osmosis, by the Amoeba Sisters! =)  Accompanying worksheet.





1. Cells

a. History

(1) The Wacky History of Cell Theory







b. The Cell

From cells, to tissues, to organs, to systems:
  1. Blood cells, skin cells, brain cells, muscle cells... lots of types of cells!  There are hundreds of trillions of cells that make up your entire body, and there are all kinds.
  2. Cells make up tissues.  A group of the same type of cell is called tissue.   Muscles cells form muscle tissue.
  3. Tissues make up organs.  An important organ is your heart, and is made up of muscle and other tissues.  The brain and lungs are other important organs made up of tissues.
  4. Groups of organs make up systems (like the digestive system, skeletal system, respiratory system, etc).
Interactive, animated tutorial: From Cells to SystemsTurn on the subtitles if needed.
See if you can get all 6 questions right at the end.  You can re-do the tutorial as many times as you like.

Really cool:  Comparing Cell Size - Use the slider below the picture to slowly zoom in.
Compare the size of a grain of rice to a blood cell!  Also see an atom and a water molecule at the end.
On the way, notice the amoeba, smaller than a grain of salt.
And the paramecium, (pear-uh-ME-see-um) about the size of an extremely tiny sliver of the corner of an amoeba.  When you zoom all the way back out, the paramecium disappears from view, but you can still barely see the amoeba.  Also see adenine - one of the nucleotides that make up DNA.



(2) Cell Structure and Function





(3) Nuclei, Membranes, Ribosomes, Eukaryotes, and Prokaryotes



All cells have a cell membrane (sometimes called a plasma membrane).  Think of a small balloon filled with jelly.  The membrane is the thin covering that keeps the cell together.  This cell membrane is what regulates what is allowed to be absorbed into the cell, and what goes out of the cell.
--Inside eukaryotic cells are many organelles (little organs), and these are also membrane-bound like the cell.  The DNA in eukaryotic cells is enclosed in a membrane-bound organelle called the nucleus.
--Inside prokaryotic cells is DNA, but there are no organelles, therefore no nucleus.  So the DNA can be seen all throughout the cell. 
►►►But with few exceptions, the two kingdoms that also have a cell wall are primarily kingdom Fungi and kingdom Plantae.  These need the added stiffness of a cell wall on the outside of the membrane to keep the plant or mushroom standing upright.  The material for the cell walls of these two kingdoms is quite different from one another, as you could probably guess.

All living things are made up of cells.
Some have many, many cells, and some have only one cell.  These are referred to as multi-cellular or single-cellular organisms.
The three basic kinds of cells are animal cellsplant cells, and bacteria cells.  All cells do not fit neatly into these categories as some are animal-like or plant-like
No matter how many cells an organism has, or which of the three basic cells an organism has, all cells are either prokaryotic cells or eukaryotic cells.

Eukaryotic cells have organelles (or tiny organs) like a nucleus, vacuoles, and other organelles.  The nucleus holds the DNA of eukaryotic cells.
Four of the five kingdoms have eukaryotic cells. (kingdoms Protista, Fungi, Plantae, and Animalia)
Prokaryotic cells contain no organelles.  The DNA does not have a nucleus to stay in.  Under a microscope, the DNA strands are visible throughout the cell.
Only one of the five kingdoms has prokaryotic cells, and that is kingdom Monera (bacteria).
SEE the difference



(4) Organelle Overview





(5) Cell Organelles and their Function Animation





(6) Vacuoles-Vesicles - what is the difference?





(7) Parts of a Plant Cell - photosynthesis, xylem and phloem, and did you know that not all plant cells have chloroplasts??







c. Diffusion and Osmosis

(8) Diffusion and Osmosis (clipped bc the osmosis part got confusing) If you want to watch it, I advise doing so after watching the next few videos.





Remember the egg experiment?  That was a demonstration of osmosis.
(9) How Osmosis Works




►Another, super cute video about Osmosis, by the Amoeba Sisters! =)
--Accompanying worksheet.



(10) Osmosis Demo





(11) A Tour of the Cell - a good review
At 11:12, he is WRONG.  Some people teach that mitochondria, which can make their own DNA, were once prokaryotic bacteria that evolved.






d. The Cell Membrane
A whole section on the cell membrane?  YES!  The cell membrane is much more complex than one may realize!  How can fluid and other things flow in and out of a cell?  How can other things be kept out of the cell??  It isn't full of tiny holes as one might imagine.  Oh, no.  It is SOOO much more complex than that!
Only our Creator could have designed such a thing.
For if evolution were to make it by chance??... well... if you took a marker and wrote the ABCs on 26 index cards... how many tries do you think it would take to throw them into the air and the alphabet line up perfectly???  And if organisms needed to evolve to live... um, how could they live before they evolved.  They didn't.
So this section is pretty important.  It's important for us to know how complex God's creation is, so that we know there is absolutely no way evolution (which claims these things were done by chance!) could have done such a thing.

(12) Cell Membrane Introduction


Remember:  Lipids are fats, and repel water. 
Part of a phospholipid (see image) is attracted to water, and part is repelled by water.  This causes the phospholipids to arrange in such a way as to make up the plasma membrane of a cell.




(13) Cell Membrane Overview and Fluid Mosaic Model





(14) Cell Membrane Proteins





(15) Cell Membrane Fluidity





(16) Diffusion and Osmosis in cells (and Active Transport)



► Read Potential Effects of Drinking Saltwater




(17) The Cell Membrane - a quick review







e. Cellular Respiration
How our body converts food into energy.

(18) An excellent Animation of Cellular Respiration - how our body converts food to energy.
Click on The Big Picture, then the play icon. 
When you watch each of the steps of Cellular Respiration, there are various checkpoints to see what you remember.

--The purpose of Cellular Respiration is to make energy.  
Your cells constantly make energy through a series of steps, divided into stages.  There are four stages of Cellular Respiration (the animation above combines 2 of them), and in each stage there are molecules that react together in a chemical reaction that produce other molecules as products.  

--In a chemical formula, the reactants (the molecules that react together) are on the left of the arrow, and the products (the molecules that are produced from the reaction) are on the right of the → arrow. 

The general chemical formula for cellular respiration is:
1 glucose molecule (from food we eat) + 6 oxygen molecules (that we breathe in) will produce  →  6 carbon dioxide molecules (that we breathe out), 6 water molecules, and about 36 molecules of ATP (energy).
     C6H12O6 + 6O2      6CO2 +  6H2O + energy
Do you recognize these molecules?  This is the reverse of photosynthesis!

--In each stage of cellular respiration, some products from the previous stage (or more than one previous stage) will then be used as reactants to make new products in the current stage.

Like factories make ingredients, and a baker might take only some of those ingredients to bake bread, then you might take only 2 slices of that bread and make a sandwich. But the leftovers are still there in the end.

The first stage of cellular respiration is (1) glycolysis, or the breaking down of glucose. This takes place in the cytoplasm
The other three stages take place in the mitochondrion.
They are (2) the formation of acetyl coenzyme A, (3) the Krebs cycle, and (4) the electron transport system.

The purpose of cellular respiration is to get energy (ATP), but right from the beginning, the first stage uses 2 ATP's as a "push" to get going, the activation energy.  This is like an investment because in the end, about 36 ATP's are finally produced.

►Click if you want to read more about each step.  Scroll down to section 8, How Cells Get their Energy.
Watch for which products are used as reactants in the next stage(s), and which products are "saved" to be used in a later stage.





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