1. Compounds of life

2. Yesterday…
Atoms, elements, and molecules

3. Macromolecules!!! Today…
We will discuss the four major types of molecules necessary for life. They are very large molecules called…
Macromolecules!!!

4. 4 macromolecules
These 4 compounds are found in all cells and are necessary for life

5. 4 macromolecules are found in our food
Carbohydrates
Lipids (also called fats)
Proteins
Nucleic acids
Each of these has different functions in the body
Why do human beings need to eat? Besides the fact that food is yummy, people (and animals) need to eat to survive. Obviously, food is needed for energy as fuel, like gasoline is needed a car. But there are other, less obvious reasons why people eat the foods they do. At this point, students are in
There are several different food groups: Fruits, Veggies, Grains, Dairy, Meats, and Sweets. Each of these groups contains something that keeps the body running correctly. These “somethings” are called “organic molecules”. In this case, “organic” does not mean the same thing it does in grocery stores (that the food has been produced without pesticides) but it takes the scientific definition, it contains the element Carbon. Most molecules that contain carbon are considered organic.
Recently, the “grains” food group has been called “carbohydrates” and the “meat” group, “proteins”. This focus on the more scientific names is great because it helps students start to make the connexion between the food groups and organic molecules. This can be used to get students thinking about how organic molecules are a part of their diet (and indeed, everything around them). However, this renaming is a little ambiguous. One might think that because only breads, pastas, potatoes, and the like are called “carbohydrates” that those are the only foods which contain the organic molecules called carbohydrates. The same goes for “meat” and “proteins”. This is not true. Proteins can be found in beans, other plant seeds, and even in dairy products as well as meats. Fruits and vegetables are largely carbohydrates. Sugars (part of the carbohydrates) can also be found in milk, and sweets are largely carbohydrates as well. Fats can be found in meat, dairy products, and sweets. Nucleic acids are found in anything that contains cells, which is ALL the food groups.
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6. Macromolecules are Polymers
Large compounds are formed by joining small individual compounds together
Monomers: the individual compounds
Polymers: many monomers joined together (poly=many)
polymer
Polymers are like a beaded necklace and monomers are like an individual bead!
monomer

7. The 4 compounds of life are organic compounds
Organic means that the molecules contain carbon!
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic Acids

8. 1. Carbohydrates Sugars for making energy
Found in bread, plant matter, grains, sugars
Can be simple or complex
All C6H12O6, but in various arrangements
Hydrogen and Oxygen ratio= 2:1
Most sugars end in suffix “-ose”

9. Two common sugars…

10. Simple carbs have one ring – monosaccharides
Carbs with two rings joined together - disaccharides
Multiple rings - polysaccharides

11. 3 main types of polysaccharides (complex carbs):
Plants store excess energy in the form of starch.
Animals store energy as glycogen.
3. Cellulose is structural support for plants. Fiber (what we call cellulose when it is eaten) is indigestible to humans.

12. a monosaccharide! So, what is the monomer of a carbohydrate?
(like glucose!)

13. 2. Lipids Waxy, oily, fatty From foods like butter and oils
Cholesterol: Important lipid that makes cell membranes flexible! But it’s possible to get too much!! (Do you know someone with high cholesterol? They probably have to watch their lipid intake!)
Many more hydrogens than oxygens
Hydrogen to oxygen ratio is always greater than 2:1

14. Saturated Fats: often solid at room temp.
Only single bonds
Animal fats, lard, butter
Not as healthy
Unsaturated Fats: often liquid at room temp.
One or more double bonds
Plant oils, nuts, avocados
Healthier

15. Good Fats Versus Bad Fats Fatty Acid Structure:
The word SATURATED means that there is no room for another hydrogen molecule to bind to it. Example, a classroom has 20 seats to fill up; every student gets to sit down. If the 21st student came in to sit, we would kick him/ her out and say “sorry, we are fully saturated”. Notice that chemical structure of a saturated fat is fully saturated with hydrogen atoms, and does not contain double bonds between carbon atoms. This means that if a hydrogen atom were to come in, there would be no place for it to bond because each atom only has 2 “hands”. This makes the fatty acid very hard to break down in our body because the carbon atoms are holding on to so many hydrogen atoms.  Therefore these saturated fats are solid at room temperature, meaning they could stay stuck in your body for quite a while until it is broken down, clogging your organs and increasing your cholesterol.
UNSATURATED
Notice how little hydrogen atoms there are in this chain compared to the saturated fat chain. This is because of the “Double bond” you see between two of the carbon atoms. Carbon atoms have four bonds so instead of using that extra hand to hold another hydrogen atom; they use it to have an extra hold to their neighboring carbon atom. The double bonds make the carbon chains kind of “bend”, making the molecules unable to get close together and therefore they are liquid at room temperature. . Unsaturated fats are better than saturated because the body can break them down easier and so they are used more quickly in the body’s metabolism
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16. So, what is the monomer of a lipid?
One glycerol (an alcohol) attached to three fatty acid chains

17. I can’t believe it’s not butter!
Did you know?
When choosing between real butter and the butter substitute, real butter is healthier???
This is because our bodies recognize butter as an organic compound and so they are able to break it down.
On the other hand, fake butter is only 1 carbon chain away from being plastic!
WHAT OUR BODY DOES: Instead of breaking down the “I can’t believe it’s not butter”, it stays around in our bodies and eventually clogs up our arteries because our body does not recognize this substance. Whereas with butter, our ancestors have been eating butter for centuries, so our genetic system is adapted to it, therefore our body already knows how to break it down. Too much butter is still bad, as it too, can clog your arteries if you have too much.
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18. What too much fat can do to you…
Too much fat can clog your arteries leading to fatal cases such as a heart attack or a stroke or Coronary Heart Disease
This is because clogged arteries may lead to a blood clot. Therefore, it will block the flow of blood to your heart.
Showing the students a picturesque image of a clogged artery due to too much fat will open their eyes about health issues surrounding a bad diet.
This is called atherosclerosis. It starts with build up on the inside of the wall of the artery. When this buildup (plaque) starts to prevent bloodflow, then heart attack happens.
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19. 3. Proteins Contain nitrogen as well as C, H, O Monomer - amino acid
Amino acids are linked together by peptide bonds (a type of covalent bond) to form proteins
R- the variable part of the amino acid

20. Peptide Bond

21. Protein structure Structure = function
How the protein folds/is arranged affects its function

22. 4. Nucleic Acids
Large complex molecules composed of phosphorous, N, C, O, and H.
2 basic kinds of nucleic acids: RNA & DNA
Monomer: Nucleotide

23. DNA and RNA contain our genetic material!
Can you see the repeating nucleotides???

24. Jamie has swim practice later today, what should he eat for lunch to prepare?
What do you think?
Whole grain pasta
A big salad
Steak
Bring on the BOJANGLES!
This poll will help students to understand the purpose of carbohydrates, which is to supply energy to the body. They should answer that pasta would be the best food to eat for energy. Then the teacher should explain why this is so. The poll will help introduce the idea that carbohydrates are made of glucose, which is the primary ingredient in cellular respiration, the method in which the body obtains energy. This should show the student how food that is taken into our bodies in one form is changed and then released out of our bodies in another.
In addition, this question is designed to help the teacher find out whether or not the students know that the simpler the organic molecule is, the easier it is to break down. If the students were previously unaware of this fact, now is a good time to tell them.

25. Enzymes – super special proteins
Enzymes speed up chemical reactions. They are also called catalysts.
Almost every reaction in your body is controlled by an enzyme!

26. Enzymes speed up reactions without altering the reaction
They lower the activation energy required for a reaction to happen
They are “denatured” (destroyed) by:
Temperature
pH changes
Enzyme names end in “-ase”

27. Enzyme specificity Enzymes are specific
Each enzyme binds to one particular substrate
Where it binds (attaches) is called the active site
When the enzyme binds it changes the chemical composition of the substrate