►This site was originally created for my kids and their cousins, because we did science together. We eventually added more friends and I ended up having science classes for five years. I am no longer adding to the site (since 2014), but will leave it up for others' use. I do post to facebook occasionally if I come across something to share. =)

►Please accept my apology for any broken links or videos that do not work. I am always disappointed when people take down their videos from YouTube. It makes it hard to find just the right replacement. And because the videos were posted years ago, I usually have no recollection of what the video was about.
I kept thinking I would have time after my kids graduated, but life has filled up my free time with new responsibilities. =)

►Please do not email, asking me to post your website link, or to review something to put on my site. Any resources posted on this site are things I had found on my own during my regular searching for material I needed at the time, and liked it well enough to post here. There have never been any affiliates on my site, and as it is no longer active, would not be worthwhile at this point. ;)
Thank you!

Angle Relationships - adjacent, supplementary, complementary

(1) Adjacent, Supplementary, Complementary, Vertical, Part 1- YayMath.org 

Adjacent, Supplementary, Complementary, Vertical, Part 2- YayMath.org 


(2) Complementary Angles - YourTeacher.com


(3) Supplementary Angles - YourTeacher.com


(4) Complementary and Supplementary Angles - TheFreeMathTutor.com


Angle Relationships - vertical

(1) Vertical Angles - YourTeacher.com


(2) Vertical Angles - TheFreeMathTutor.com


Parallel Lines and Transversals - Corresponding Angles, Same Side Interior, Same Side Exterior, Alternate Interior, Alternate Exterior

1) Corresponding Angles - TheFreeMathTutor.com


(2) Parallel Lines, Corresponding Angles, Transversal, Same Side, Alternate, etc. Part 1 - YayMath.org  (You can skip some if you want.  Watch 1:55-4:45, then 6:20 to the end.)


(3) Continuing on to Same Side Interior, Same Side Exterior, Alternate Interior, Alternate Exterior, Part 2 - YayMath.org

►Awesome interactive site!  Practice what you've learned.

Total Lunar Eclipse and Winter Solstice

There is to be a total lunar eclipse tonight, nearly at the same time as the Winter Solstice.  It has been 372 years since these occurred on the same day.  The Winter Solstice is the moment at which the North Pole is tilted the farthest away from the sun.  This is the shortest day of the year and the beginning of winter in the Northern Hemisphere.
These two events are unrelated, but they do not usually happen on the same day.
You can see the eclipse if you don't mind staying up awhile!
I'm telling my kids that if they want to stay up, then they have to look up some information first and tell me a few things they've learned, hee hee!
The moon starts into the earth's shadow at 1:33am EST and will be totally eclipsed from 2:41 to 3:53 EST.   This is when the moon will be red. 
You lucky people in the Pacific Time Zone!  Your clocks will be three hours earlier than mine!
I hope I can stay up!  Maybe I need a nap.  Zzzzz....
Thanks to Apologia posting this on Facebook.

Total Lunar Eclipse on Aug. 28, 2007, seen from Kapiolani Park in Honolulu, Hawaii. Shot thru a telescope, about every 5 minutes.


Why does the moon turn red?  Simply put, it's for the same reason that sunsets are red.
White light is made of red, green, and blue. Our atmosphere filters out the shorter-wavelength light (blues, greens), so right on the edge of the earth's silhouette, the light from the sun that is hitting the moon is red.
If you were on the moon during a lunar eclipse, you would see a red ring around the silhouette of the earth.
The moon has no light of it's own and reflects whatever kind of light from the sun hits it.

--Last year in Physical Science, we did a very simple experiment (sheet of paper, red marker) that shows how the light spectrum works this way.  (Scroll down -- it would be the last one, of course!)



►At EarthSky.org, watch a video and/or read why "there won’t be a total lunar eclipse this far north on the sky’s dome until December 21, 2485."
Scroll down for specific times for different time zones. 
►More information on Lunar Eclipses, including a list of future eclipses, and from what region of the earth they can be seen.  Scroll down.
♦Learn more about light and why you see a rainbow the way you do. 

UPDATE: Here is the eclipse from yesterday.

Winter Solstice Lunar Eclipse from William Castleman on Vimeo.

Scientific Notation

(1) From standard form to scientific notation - YourTeacher.com 


(2) From scientific notation to standard form - YourTeacher.com 


(3) Scientific Notation I - MuchoMath (Professor Perez and Charlie) 


(4) Scientific Notation II - MuchoMath (Professor Perez and Charlie) 


Scientific Notation


Long Multiplication a different way

I think this is an excellent way to teach multiplication.  The child can easily see that you are multiplying parts of a larger problem, then adding them together.

Apologia Biology, Module 7, Cellular Reproduction and DNA

Quizlet Vocabulary Game, M7 
M7 Recap Blog Post at Sahm-I-Am


(1) p. 197-198, Experiment 7.1, DNA Extraction
Our class did this experiment last year.  (See our results)
Here are instructions if any other blog readers need them, and an instructional video.
►And just for fun, you can try this DNA Extraction Virtual Lab.

This is Applie's video below from when her class did this, and here is her Module 7 post.






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(2) p. 198b-200, Protein Synthesis - Part 1: Transcription
"Synthesis" means the making of or production
The point of the next 2 sections is to show how proteins are made from DNA.
Cells synthesize, or make, proteins that result in the traits that DNA gives us.  The cell's genes determine what kinds of protein a cell will make, which determines the job of that particular cell.

A scribe is someone who writes down a copy. You can see the word scribe in transcribe, and script in transcription. Transcription means to copy or transcribe. 
Something called RNA is what helps make the copy of DNA, which is in the nucleus of the cell.   RNA looks like DNA, but it ends up being only a single strand of nucleotide bases. 

The differences between DNA and RNA are:
DNA: has nucleotide base pairs of cytosine & guanine, and adenine & thymine.
►See diagram of DNA strand. (source)
RNA: has individual nucleotide bases of cytosine, guanine, adenine, and uracil, but they are not in any particular order yet.  They will match up to corresponding DNA nucleotides so they will be in the correct order for transcription (copying)
--There are two nucleotides that are different - uracil in RNA, and thymine in DNA.
Uracil in RNA will match up to adenine in DNAAdenine in RNA will match up to thymine in DNA, so U-A, and A-T.
DNA: has deoxyribose (on the "rail" of the "ladder").
RNA: has ribose.
DNA: is twisted in a double helix of paired nucleotides.
RNA: usually in a single strand of joined nucleotides.

►See diagram of DNA and nucleotides.
Only a certain section of DNA will be copied.  As this section of the DNA strand unwinds, individual RNA nucleotides match up to compatible DNA nucleotides and take a "negative snapshot" of the DNA code.  For example, if the DNA has a nucleotide of guanine, an individual nucleotide of RNA cytosine will match to it.  If the DNA has a nucleotide of adenine, an individual nucleotide of RNA uracil will match to it.
Before, the RNA nucleotides were individuals, and not in a strand since they had to match up to the DNA in the correct order.  Now they are a "negative" copy of the DNA, and will be used by the ribosome to make a protein.
This is copying, or transcribing the DNA code.





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(3) p. 201- 204, Protein Synthesis - Part 2: Translation

Transcription and Translation.  A polypeptide is a chain of amino acids.  Poly means many.


After the RNA "negative" of the DNA is made, the RNA takes this negative out of the nucleus and into the cytoplasm to a ribosome.  Because of this, it is called messenger RNA, or mRNA
Near the ribosome is a different kind of RNA called transfer RNA, or tRNA.  This tRNA contains a special sequence of three nucleotides called an anticodon.
A special sequence of three nucleotides on mRNA is called a codon.
The codon and anticodon aren't just any three nucleotides, but certain various combinations.

The tRNA is bonded to an amino acid, but only a certain type of amino acid will bond to a certain sequence of three nucleotides in the tRNA.
For example, if the three-nucleotide anticodon is made up of uracil, uracil, and cytosine, the tRNA is bonded to the amino acid lysine.  (p. 202 shows a few more combinations).
A codon on mRNA attracts a specific amino acid.  Then the tRNA links up to the mRNA.

After the tRNA links up to the mRNA, the amino acids on each of the tRNA anticodons bind together to make a protein.
The chain of amino acids that make a protein is called a polypeptide. (poly- means many)
(The first 30 seconds of this video are the same as a video already posted, but good to see it again.)




Learn the difference between mRNA codon and tRNA anticodon, and how a chain of amino acids form a protein.  A stop codon is a special codon that signals the stopping point for translation.
Learn which codon is the starting point for Translation (which 3 letters).


Through studying DNA, a man realizes only God could have created all this!



►To practice what you've learned, go to the DNA Workshop
Click on DNA Workshop Activity, then in the pop-up window on the top right, click on Protein Synthesis.
Follow the directions to first build RNA, then match tRNA anticodons to mRNA codons to build proteins from the amino acids.
If you don't understand this, go back and watch all the above videos, and re-read the textbook.   



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(4) p. 205-211a, Mitosis: Eukaryotic Asexual Reproduction

Exp. 7.2, Mitosissince we do not have a microscope, watch/read what is posted here.

Mitosis is the process of cells splitting and multiplying, for repair of cells, or growth of new cells from existing cells.  
This is asexual reproduction.

Mitosis is the growth of new cells, either to replace damaged cells, or for a growing person or unborn baby.
But before Mitosis begins its 4 stages, the DNA that is in the nucleus must duplicate itself into sister chromatids, then coil up into chromasomes.







Exp. 7.2, Mitosis
►Watch this video of Mitosis.  Click Animation.
[If you need to, press your F11 key to make the screen larger. Sometimes clicking F11 while in a different tab works better.]

►After watching the animation, click Tutorials at the bottom.
Below that, 5 Interactive Tutorials are listed:   
Roles of Mitosis, Overview of Mitosis, Cell Cycle, Stages of Mitosis, and Summary.    
Do all except the middle one, the Cell Cycle.  Mastering these is important.


Learn the 4 phases of Mitosis, and briefly what each one does.  You can remember their order by the acronym PMAT.  (Interphase is not a phase of mitosis; it is an 'in-between' phase.)  
After completing the Summary, click on each cell to see descriptions of each cell.
►Fill in this printable Study Sheet for Mitosis.

►This will help you understand what you are drawing & labeling in Fig. 7.6, p. 208 which is also your assignment for today.
If you don't understand this, go back and watch all the above videos, and re-read the textbook.   





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(5) p. 211-213a, Diploid and Haploid Cells
--All living things have different numbers of chromosomes.  An onion has 16 chromosomes in each cell; a horse has 64; and a carp has 104.
--Humans have 46 chromosomes in each cell.  The chromosomes are in pairs, so humans have 23 pairs in each cell.
Each pair consists of similar types of chromosomes, and therefore they are called homologous chromosome pairs, or homologous pairs.  Homo- means same, but homologous means similar, but not identical.
Each chromosome is attached to its sister chromatid (its duplicated chromosome) at the centromere, giving them their X shape.  Two sets of these make a pair of similar, homologous chromosomes.  XX.
--The 23rd pair of chromosomes are chromosomes that determine sex.  In a female these are both X chromosomes, or XX, but in a male, they are XY.  So in males, the 23rd pair is not homologous.
►See image of Human Chromosomes

Read carefully.
--When a cell's chromosomes come in pairs, it is called a diploid cell.  XX, XX, etc.
--Cells with chromosomes that do not come in pairs are called haploid cells.  A haploid cell has only one representative of each chromosome pair.  X, X, etc.
Cells can have 23 pairs of chromosomes, or 23 chromosomes, depending on what phase the cell is in.

There is also a diploid number and a haploid number.  This can be rather confusing, but read carefully:
--The diploid number represents the total number of chromosomes in 1 cell or counting both partners in the pair.  In other words, the total number of chromosomes in a diploid cell.  46.
--The haploid number is the number of chromosomes in a haploid cell.  23.  Makes sense, right?
But it is also the number of homologous pairs in a diploid cell.  23.

►►So how can a diploid cell have a haploid number?  A diploid cell has homologous pairs, but a haploid cell does not have any pairs.  So how can this be?
►It's like saying there are 46 people at the party, and 23 couples.  But 23 is also the number of boys.

This is not a haploid cell, but a haploid number.  A haploid number is the number of chromosomes represented by one chromosome from each pair in the organism.  So in a human haploid cell, there is only one chromosome from each pair, equaling 23; in a human diploid cell, one chromosome from each pair will still be 23.
(Thanks to the teachers at Apologia for being willing to email me several times until my brain finally got it!)





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(6) p. 213-218a, Meiosis: The Cellular Basis of Sexual Reproduction
The purpose of meiosis is for sexual reproduction.  
It is the process by which a diploid cell forms a haploid cell called a gamete (eggs and sperm are gametes).


 Meiosis
►Watch this video of Meiosis.  Click Animation.
[If you need to, press your F11 key to make the screen larger. Sometimes clicking F11 while in a different tab works better.]

--After watching the animation, click Tutorials at the bottom.
--Below that, 5 Interactive Tutorials are listed:   
Homologous Chromosomes, Meiosis I, Meiosis II, Comparing Mitosis and Meiosis, and Summary.
Mastering the first 4 are important.
►Use this comparison printable Study Sheet for Meiosis.  You will be able to fill this in after you complete Comparing Mitosis and Meiosis, but you should do all the first 4 Interactive Tutorials to be able to understand this.
►Watch this video to be able to answer the last question about Recombination.
This is why parents can have children that look so different from one another.
These haploid cells (that were produced by diploid cells) will have only 23 chromosomes (one from each pair), and are the cells that determine sex.  These are called gametes.  Gametes are the eggs and sperm.
After an egg and sperm unite, the resulting cell is called a zygote.  The zygote now is a diploid cell with 46 chromosomes (or 23 homologous chromosome pairs).
The zygote will multiply again and again by mitosis (not meiosis), forming a baby.

After you understand meiosis, here is a fun video to watch.  =)
The DNA first coils up into chromosomes (see image or Fig. 7.4, p. 205).





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(7) p. 218-222, Viruses
Learn The Lytic Pathway (or Lytic Cycle) for cells in general, (not just the one for bacteria in Fig. 7.14).
►Read the paragraph on p. 219 that ends in "This process is called the lytic (lih' tik) pathway."
Sorry about the green flashes, etc.  This video must have a virus, hehe!


The virus transcribes and translates.  Transcription and Translation.
This is how the cell reproduces the virus.  The virus cannot reproduce itself.


Apologia Biology, Module 6, The Cell

Animal Cell Pizza!
The Secretion Vesicle looks like someone took a bite, haha!  =)
Quizlet Vocabulary Game, M6, part 1
Quizlet Vocabulary Game, M6, part 2
Quizlet Vocabulary Game, M6 
M6 Recap Blog Post at Sahm-I-Am
Read Julie's Tip for learning the vocabulary.

Go to at least one of these links each day to study the organelles you are learning. 
♦ Centre of the Cell  Watch the moving parts of cells.  Click on the white circle connected to an organelle to see the name and function.  Very simple and easy to understand.  Does not include all the organelles, tho.
♦ Cells Alive!  See if you can recognize and name all the organelles.  Read the organelles at the bottom and see if you can find them in the picture.  Hover your mouse over an organelle to see if you are correct.
♦ Virtual 3D Cell  Hover your mouse over the 3D cell.  Click on the organelles you are learning for more information and a closer view.  Some can zoom or rotate.  Some will open for you to see inside. If it says click next, click one of the arrows on the left. ►◄ 


Games, etc:
Cell Quiz
Plant cell
Plant and animal cells
♦ Words to Plant and Animal cell songs.

Look here for examples of Incredible, Edible Cells:
2008, Michelle's class at Applie's Place
2009, Michelle's class at Applie's Place
2010, Michelle's class at Applie's Place
2010, Julie's class at Mindful Ramblings (scroll down.  You can click on the picture to enlarge.)
I also like this cake made from a soccer ball pan and fondant.



(1) p. 161-163, Cellular Functions
There are 11 functions of plant and animal cells listed in this first section of Module 6.  Three of the functions aren't listed as a vocabulary word, but they are in bold print in the text.
Some functions both plant and animal cells perform; other functions are specific to only animal or only plant cells.  


I couldn't find a video that covered this very well, so here is an overview of cells. 







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(2) p. 164-166a, Cell Structure... The Cell Wall... The Plasma Membrane
Near the bottom of p. 164, it says, "...cells are small for a reason... the volume of materials in a cell increases with the cube of the radius of the cell."  After a brief introduction, he explains why cells are small and will not keep growing larger and larger.




Plasma Membrane






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(3) p. 166-167a, The Cytoplasm

►Watch this short video about the cytoplasm.  Scroll down a bit.

Cytoplasmic Streaming (remember, cyto means cell) is the movement of the cell's cytoplasm, transporting things such as nutrients, proteins, etc.  
You will soon learn about active transport and passive transport.   


Here is cytoplasmic streaming in the chloroplasts in a leaf.  You don't need to watch it all.





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(4) p. 167-174, various parts of a cell

This video covers several organelles in the cell, but not in the order they are in your textbook.
p. 167-168, and 171
Endoplasmic Reticulum/ER, Ribosomes, Gogi Body (same as Gogi Apparatus)
Lysosomes, Mitochondrian 



p. 169
Vacuoles and Vesicles


Also listed in your text is the vocabulary word Phagocytosis.
Phago- means to eat or engulf; cyto- or means cell.
This should help you remember what a Phagocytic vacuole is as well.  (The ic on -cytic is the adjective part that means having to do w/ cells)
Read your definitions and study all your diagrams!  =)


p. 172-173
Centrioles and Cytoskeleton
Oddly, I found a strange video that goes over the 2 remaining organelles the above videos didn't cover.



Plant Cell



► Play this Cell Quiz.  Play it several times if you like.




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(5) p. 175-176Experiment 6.1, Cell Structure I  
My Class:  Look here at onion cells (the first 3 pics), and on the blank, unlined lab sheet I gave you, draw each magnification.  Label which magnification each picture is. 




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(6) p. 176-180, How Substances Travel In and Out of Cells

Before watching these videos, study Figure 6.7, The Construction of the Plasma Membrane.

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.

The Plasma Membrane



Passive Transport and Active Transport.
Active Transport requires energy, called ATP.



Animal Cell
Near the end, see the centrioles. In the Animal Cell Pizza picture at the top of this post, we used pieces of celery to represent the centrioles.




Examples of Passive Transport
►Remember diffusion and osmosis - scroll down and read the part that is below the pictures of eggs.
Remember, osmosis occurs in an attempt to "even up" the concentration or dilution of solutes in the water on both sides of a semi-permeable membrane, such as the membrane of a raw egg or of a cell.


Watch three videos:  


(a) Isotonic solution - a cell is said to be in an isotonic solution when the amount of concentration in the cell is equal to amount of concentration that is in the solution the cell is in.
Your kidneys get rid of excess solutes in the blood to ensure that the bloodstream stays isotonic with your red blood cells.  
Evolution?  I think not.  Or you'd be dead before you "adapted" to everything that is necessary to live!

(b) Hypertonic solution - the amount of concentration in the solution (that the cell is in) is greater than the amount of concentration that is in the cell itself. This causes the cell to lose water because the cell's water is drawn toward the higher concentration that is outside of the cell.
This causes the cell to shrink in on itself or implode (opposite of explode).
This collapse of a walled cell's cytoplasm (remember, cyto means cell) due to a lack of water is called plasmolysis  
This is why when a person drinks ocean water, the water in their cells will move out of the cells by osmosis to the higher concentrated salt water, which can be fatal.


(c) Hypotonic solution - the amount of concentration in the solution (that the cell is in) is less than the amount of concentration that is in the cell itself.  This causes the cell to absorb more water and swell up due to osmosis, and causes the cell to explode.
This rupturing of a cell due to excess internal pressure is called cytolysis.  (remember, cyto means cell)  

(a) Red blood cells in an isotonic environment


(b) Red blood cells in a hypertonic solution causes plasmolysis (the cell implodes and shrivels)


(c) Red blood cells in a hypotonic solution causes cytolosis (the cell explodes)







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(7) Experiment 6.2, Cell Structure II  p. 181-182 


My Class:  
We don't have a microscope, so use these links that show a small cut out piece of a leaf, with its layers.
Leaf 1, Leaf 2, Leaf 3

On the blank lab sheet you were given, draw a diagram of a cut view of a leaf.  You may use different parts from either of the diagrams at the links.

►►Label these parts:
xylem, phloem, and vein, | stoma and guard cells, | and the chloroplasts.
•The chloroplasts are not labeled in the above diagrams of the cut leaves.  However, I bet you can find them.  They are green, and they are in the palisade layer.  The little dots are the chlorophyll that is in the chloroplasts.

1-6. On the back of your page or on a separate lab report page with lines, briefly explain (in your own words, not mine that I typed here) what each of those ↑ 6 parts do.
7. Also explain what plasmolysis does.
8. From the videos above, tell what word is the opposite of plasmolysis?


•Xylem (zy' lum) and phloem (flow' um) tubes are together in a vein
•The xylem tubes transport water and minerals (that are taken in by the roots) up throughout the plant.
•The plant makes glucose in the chloroplasts that are in the leaves.  The phloem tubes then transport the glucose down to all parts of the plant.

How to remember which way xylem and phloem flow.



•The stomata (sing. stoma) are openings on leaves that allow carbon dioxide to enter the plant and oxygen to exit the plant, as well as the release of water vapor. 
•Pairs of guard cells on the leaf open and close the stoma to control this process.  They open or close depending on if they are full of water or not.  Remember from p. 169 that turgor pressure from being full of water helps keep a plant rigid.  The same applies to guard cells.

This celery regains turgor pressure as the vacuoles in each of its plant cells fill with water.



Stomata on leaves are usually open during the day during photosynthesis, and closed at night.  Sometimes stomata close during the day if it is too hot and the plant starts losing too much moisture.  At these times, photosynthesis ceases.
►See image of guard cells when they are open and when they are closed.





Remember the video that is posted above of Cytoplasmic Streaming.  (Sometimes putting a leaf in warm bright light will cause the streaming to begin.)
Adding salt water (high concentration of solute) will cause osmosis, and the cells will begin to lose their cytoplasm.  This is called plasmolysis. (animation) When you see a plant wilt, it is beginning to experience plasmolysis, though not from salt water; just from a lack of water.
Watering a plant can reverse plasmolysis, and the plant will once again "stand up" due to turgor pressure.
In this video, you can see the process of plasmolysis begin around 40 seconds.





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(8) p. 182-185, How Cells Get their Energy

►An excellent animation of Cellular Respiration.
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.
This animation combines Step 2 and 3 below↓ into the Krebs Cycle.
These animations are not exactly like Apologia Biology, but it will help you understand the process.


--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, 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.
--In each stage of cellular respiration, some products from the previous stage (or more than one previous stage) are now 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 now 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.
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.

Aerobic cellular respiration is the converting of glucose into a usable form of energy.  This energy is stored as adenosine triphosphate, or ATP.  It is called aerobic cellular respiration because this means of cellular respiration uses oxygen.
The general equation for cellular respiration is:
1 glucose molecule + 6 oxygen molecules (after a very complicated series of steps) will produce → 
6 carbon dioxide molecules, 6 water molecules, and about 36 molecules of ATP (energy).
C6H12O6 + 6O2 → 6CO26H2O + energy
Do you recognize these molecules?  This is the reverse of photosynthesis!
Now we will discuss a little about those very complicated steps.  =)

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, 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..

Stage 1 Glycolysis 
A monosaccharide molecule goes into the cytoplasm where enzymes catalyze (speed up) a reaction that causes the monosaccharide molecule to lose some hydrogen atoms and convert one molecule of glucose into 2 molecules of pyruvic acid (sometimes called pyruvates) with some hydrogen (H) left in the product as well.  Two ATP's are used to get this process started.  It also produces 2 more ATP's (energy).
C6H12O6 → 2C3H4O3 + 4H + energy
  glucose        pyruvic acid               2ATP's

Stage 2:  The formation of acetyl coenzyme A
The 2 molecules of pyruvic acid head to a mitochondrion.  As they cross into the mitochondrion, the pyruvic acid molecules are broken down, freeing carbon dioxide and hydrogen (which are products in the formula below).  Then something new is introduced.  Two proteins (called coenzyme A) attach to the remains of the pyruvic acid, forming 2 acetyl coenzyme A's.  (The - sign in the formula below does not mean minus.  It means it is attached.)  Two other products of this chemical reaction are carbon dioxide and hydrogen.  This stage is sometimes called the "oxidation of pyruvic acid."
The coenzyme A's are neither used up nor produced.  They simply cycle through the stages of respiration.
No additional ATP is formed in this stage.
2C3H4O3 + 2(coenzyme A) → 2C2H3O-(coenzyme A) + 2CO2 + 2H
pyruvic acid         a protein                        acetyl coenzyme A

Stage 3:  The Krebs Cycle
This is the first stage that uses oxygen.  The 2 molecules of acetyl coenzyme A react with oxygen to make hydrogen, carbon dioxide, and coenzyme A again.  This is actually a summary of a very long, complicated procedure (like this explanation isn't complicated?!?)  =)  Two ATP's are also produced. 
2C2H3O-(coenzyme A) + 3O2 → 6H + 4CO2 + 2(coenzyme A) + energy 
      acetyl coenzyme A                                                               proteins              2ATP's
 
Stage 4:  The electron transport system
The hydrogen from the previous three stages reacts with oxygen to make water and energy. This stage produces the most energy of all four stages.  Thirty-two ATP's, for a total of 36.
12H + 3O2 → 6H2O + energy
                                          32 ATP's

In each stage, you need to look at the product and see what of that is used in the next stage, and what is not used.
•In stage 1, glycolysis, the products are 2C3H4O3 (pyruvic acid), 4H (hydrogen), and 2ATP's (energy).
The 2C3H4O3 is used as a reactant in the next stage, but the 4H and 2ATP's are not. (so we "save" those in our mind)
•In stage 2, the formation of acetyl coenzyme A, the products are acetyl coenzyme A, 2H and 2CO2 (carbon dioxide).
The acetyl coenzyme A is used as a reactant in the next stage, but the hydrogen and carbon dioxide are not.  (add those to your total so far)
[note here that in stage 2, two coenzyme A's are used, and in stage 3, two coenzyme A's are produced.  The net result is that nothing changed.  Two coenzyme A's will be produced and used over and over again with each full cycle of cellular respiration.]
•In stage 3, the Kreb's cycle, excluding the coenzyme A's, the products are 6H, 4CO2, and 2ATP's.  The 6H (as well as the previously produced 4H and 2H) will now be used as reactants in the last stage, and 3O2 (oxygen molecules) are also added in as reactants in the formula.  The 4CO2 and 2ATP's are not used as reactants in the last stage.
•In stage 4, the electron transport system, all the 12H are used as well as 3 more O2. 6H2O (water molecules) are left, and 32ATP's are produced.

We started with one glucose molecule, and along the way added 3 oxygen molecules, then 3 more.
Here is total what was used, and what is left:
C6H12O6 + 6O2 → 6CO26H2O + energy (36ATP's)
This is cellular respiration, and the formula is the opposite of photosynthesis.
In cellular respiration, we use glucose and oxygen in our bodies.  We get carbon dioxide (which we breathe out as a waste product), water, and energy.  Our catalyst to speed up this process is enzymes.
A plant uses the energy from the sun, carbon dioxide, and water to produce glucose for itself, and gives off its waste product of oxygen.  Remember, the catalyst for plants is chlorophyll.
There is a video on the MMCD, but you really need to study your textbook first, and what I have written here.





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(9) p. 186-189 ATP and ADP
Adenosine Triphospate (one adenosine and three phosphates)
Adenosine Diphosphate (one adenosine and two phosphates)


Synthesized means produced.
Making ATP from ADP in the Mitochondrion



►Please watch this very thorough video of How Cells Obtain Energy.


Apologia Biology, Module 5, The Chemistry of Life, Part B

Quizlet Vocabulary Game, M5  
M5 Recap Blog Post at Sahm-I-Am 

--Review how to balance equations with this video.
--Then play Balancing Act! Choose Beginner.



(6) p. 140-142a Photosynthesis
In photosynthesis, a plant takes (1) carbon dioxide, (2) water,  and (3) the energy from sunlight and converts them into (A) a simple sugar called glucose which the plant needs for food, and into (B) oxygen which it does not need, but gives off for us to breathe.  
(there is a fourth thing needed, mentioned below)

"Carbon dioxide and water interact to make glucose and oxygen."  
Carbon dioxide + water → glucose + oxygen

--But it takes 6 molecules of carbon dioxide and 6 molecules of water to get 1 molecule of glucose for the plant, and 6 molecules of oxygen left over.  The oxygen is sometimes called a by-product or waste product.  It isn't waste to us, but it is to the plant.
6CO2 +  6H2O → C6H12O6 + 6O2 
Memorize this chemical equation.  Know the elements in each molecule, and what molecule they combine to make.  (For example, H2O is 2 atoms of hydrogen and 1 atom of oxygen.  Together they make water) 
►The molecules to the left of the arrow are called reactantsThey react to make a product.
So the 6 molecules of carbon dioxide and 2 molecules of water are the reactants.
6CO2 +  6H2O → C6H12O6 + 6O2 
The molecules to the right of the arrow are called products.
So the 1 molecule of glucose and 6 molecules of oxygen are the products.  They are produced as a result of the chemical reaction.

►►In order for photosynthesis to happen, more is needed than just carbon dioxide, water, and sunlight.
A fourth thing is needed called a catalyst, which speeds up a process.  And in a plant that catalyst is usually chlorophyll.  Chlorophyll, a green pigment, exists in a part of the leaf called chloroplasts.  The job of chlorophyll is to speed up photosynthesis so plants will have enough glucose for food.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (7) p. 142, Organic Chemistry ►An organic molecule is one that contains only carbon and any of the following: hydrogen, oxygen, nitrogen, sulfur, and/or phosphorous. If you memorized these last week, you will easily recognize these six elements.  Look in your textbook on p. 142 for examples of organic molecules and some that are not, and why.  Memorize these. ►Photosynthesis is an example of biosynthesis since photosynthesis takes smaller molecules (water and carbon dioxide) and makes a larger one (glucose).
6CO2 +  6H2O → C6H12O6 + 6O2
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (8) p. 142-146 Carbohydrates ►Carbohydrates contain only carbon, hydrogen, and oxygen.  You can see the 'carbo' in the name, for carbon.  And hydrogen and oxygen make water, thus 'hydrate' in the word carbohydrate. You may know that carbohydrates give you energy, and you've learned that glucose is a simple sugar. Look at a molecule of glucose: C6H12O You can see there are 6 atoms of carbon, 12 of hydrogen, and 6 of oxygen. There are twice as many hydrogen atoms as there are oxygen.  This is the same ratio as one molecule of water, H2O. ►When a molecule of glucose is drawn in structural formula, it shows which atoms are linked to which. When the atoms are linked in a straight line, we call it a chain structure. (on the left below) The chain structure of the glucose molecule below has a line of Carbon atoms, called a carbon chain.  But many atoms have more than one structural formula. The most commonly accepted form of glucose is the ring structure. These diagrams are not drawn exactly like the ones in the textbook, but if you look closely and compare to those in your textbook, you can see these indeed do represent glucose. In the ring structure on the right below ↓, CH2OH consists of the same atoms as drawn in your textbook, and the same as the chain structure here on the left, where C links to 2 H's, and to OH. You will remember in your textbook, in the chain formation, one oxygen atom had 2 lines linking to a carbon atom.  Here in the chain formation on the left, the solitary oxygen atom does have 2 links. If you look carefully and find that same oxygen atom in the ring formation on the right, you will again see the oxygen has 2 links linking to carbon. ETA: You will notice that the Oxygen is always connected to the Carbon.  That is why in the chain structure here on this blog, HO is written instead of OH.  The chain structure is vertical, so HO must be written this way so that the O is connected to the C. (I emailed Apologia; ha, I am not that smart!)  I was also told whether it was written as OH or HO did not matter as long as the Oxygen was attached to the Carbon.  This is not apparent in the figures in your textbook, as the picture is drawn horizontally, and the connecting line seems to attach to both the O and H, but here it is clear that the Carbon is attached directly to the Oxygen.
She says, "...it is very polar... to which water molecules can hydrogen bond." You may remember from Physical Science that water has a hydrogen bond and is polar. (8b) p.144, Isomers  (Carbohydrates, cont.) Isomers are two different molecules that have the exact same chemical formula.  They are different molecules because of their different structural formulas.
Glucose and Fructose are isomers.  They have the same atoms (C6H12O6), but in their structural formula, their atoms are linked together slightly differently.  This is the reason they taste different.   (8c) p. 145-146 (Carbohydrates, cont.) Glucose and fructose are monosaccharides, also called simple sugars.  You may know that the prefix mono- means one. Disaccharides are carbohydrates made up of two monosaccharides.  You may remember that Carbon-Dioxide (CO2) has one atom of carbon and two atoms of oxygen.  Di- means two. Polysaccharides are made up of more than two monosaccharides.  Poly- means many. Table sugar is not glucose (a monosaccharide), but is a disaccharide called sucrose. Sucrose is formed when glucose and fructose (which are isomers) chemically react in a dehydration reaction. When something is dehydrated, water is removed.  So from the combined molecules of glucose and fructose, H2O is removed, and the result is sucrose (a dehydration reaction) -- C12H22O11  
C6H12O6   C6H12OC12H22O11 + H2O
Remember, sucrose is a disaccharide because it was formed from two monosaccharides in the process of dehydration. ►What two molecules combine in a dehydration reaction to make the disaccharide lactose? When several monosaccharides link together, it is called a polysaccharide.  Polysaccharides aren't usually sweet.  An example is starch, and is found in most plants.  When a plant has extra monosaccharides, it will store them as polysaccharides by having many dehydration reactions that link the monosaccharides together. Kind of like when your Mom has a lot of a apples, she may dehydrate some to use in baking later, except in a dehydration reaction, not only do the monosaccharides lose water, they are actually combined into polysaccharides. If they are now polysaccharides because they have lost water, what will the plant do to turn them back into monosaccharides?  The opposite of dehydration is hydration.  The plant breaks down disaccharides or polysaccharides back into their monosaccharide components by adding water.  This is called hydrolysis.  (Think of the word hydrate.) When humans and animal have excess carbohydrates, their bodies make a starch called glycogen. So the reverse of the dehydration of fructose and glucose to form sucrose, would be hydrolysis of sucrose to make glucose and fructose.  This chemical reaction is achieved by honeybees when they make honey. ►If you want, you can read more here about this and other processes we have studied.  Also see "Respiration" which is mentioned in the next Module.  See if you recognize the molecules.  =) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (9) p. 146-147, Organic Acids and Bases Acids usually taste sour, while bases tend to taste bitter.  Fruit juice contains acid, and many cleaning products contain bases.
If acids and bases react together, they usually form water and another class of molecule called "salts."  Table salt is one example.
Acid Group
►Organic acids contain a certain pattern of atoms bonded together:  Oxygen has a double bond with Carbon, indicated by 2 lines, and the Carbon has a bond with OH.  (O=C-OH) This pattern is called an acid group. → (In the chain structure of glucose on p. 143 (top of page), you see a double bond of C with O, but that same C does not bond directly with OH, that molecule does not contain an acid group, and therefore is not an organic acid.) When you see this grouping withinin a molecule, you will know the molecule is an organic acid. This special grouping is NOT a molecule by itself; it is a grouping that can be IN a molecule.
This molecule has an acid group,
so this molecule is an organic acid.
← This molecule has an acid group in it, so the whole molecule is an organic acid.Organic bases have a group of atoms in common called the amine group, but in this chapter, organic bases are just mentioned and not discussed.  If you or someone you know has a pool, you know that they may use pool strips to check the pH of the water to keep it from turning green!  Keeping the pH balanced is necessary for clean water. The pH of substances other than water can also be measured. ►See videos of what we did.  (scroll down) The pH scale runs from 0-14.  For solutions measuring lower pH than 7, the lower the pH, the more acid. For solutions having a pH higher than 7, the higher the pH, the more like a base the solution becomes.  These are said to be alkaline. Look at the chart on p. 147 to see which substances are acids or bases, and which are neutral. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
(10) p. 148-149, Lipids Lipids (or fats) link to glycerol in a dehydration reaction.  One glycerol molecule and 3 fatty acid molecules have a dehydration reaction to make 1 lipid molecule and 3 water molecules. Lipids cannot be dissolved in water.  An example is cooking oil.  Lipids are said to be hydrophobic.  This does not mean it is afraid of water, haha, but that is a good way to remember it.  =) Animals can convert excess carbohydrates into glycogen, but lipids can actually store twice as much energy for when food is scarce.  Saturated fats are called "saturated" because they have all the hydrogens it can take.  It is "saturated" with hydrogen. These saturated fats have no double bonds between carbons. Unsaturated fats have at least one double bond between carbon atoms. Do not watch this until after you have thoroughly studied pages 148-149. Then watch it twice and try to catch all the things you have learned.  =) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (11) p. 149b-154, Proteins and Enzymes Proteins come in many different shapes and sizes and are very complex.  Their basic building blocks are amino acids.  When amino acids link up using a dehydration reaction, a peptide bond forms. The structural formula for a protein very complex.  An average amino acid has about 20-40 atoms, and the most simple protein has 124 amino acids.  But an average protein has several thousand amino acids! Enzymes are a special class of proteins that act as catalysts.  For animals, these catalysts speed up the breaking down process of polysaccharides and disaccharides. Most enzymes do their job based on the shape that the enzyme molecule has.  After studying 151-152 and Figure 5.9, watch this video. Remember, lactose is a disaccharide.  If the particular enzyme in someone's body that is specifically designed  for the lactose disaccharide is unable to work properly, a person will not be able to digest the lactose that is in milk.  There are medicines to help this, however. ►Be able to explain what happened in Experiment 5.3, The Fragility of an Enzyme. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (12) p. 154-156, DNA ►Study Figure 5.10 as you read the text, learning the parts of a DNA strand. DNA, or deoxyribonucleic acid, is formed in a double chain. These two chains are made up of three basic parts:
  1. deoxyribose (a simple sugar that contains 5 carbons)
  2. phosphate group (an arrangement of 3 things:  phosphorous, hydrogen, and oxygen atoms - see the picture on the right of Figure 5.10 in your textbook)
  3. a nucleotide base
The nucleotide's base can be one of four different types:  adenine, thymine, guanine, or cytosine.  Notice which pairs are consistently linked together in this image.   (source) The phosphate groups link to the deoxyribose units, which is what the outer "rails" of the DNA strand is made of.    Click for a cool DNA game.  =)