FOOD Food provides energy for all of the

FOOD Food provides energy for all of the body’s functions. Food is the fuel that contains energy from the sun. The sun’s energy along with carbon dioxide is captured and stored by plants through the process of photosynthesis then passed along to fruits, seeds, & the animals that eat them. Humans eat these foods & burn the fuel they contain to release the stored solar energy. As long as we live, we have to eat and eat often! Text from: Eating Well for Optimum Health Andrew Weil, MD

2. Food provides the building blocks of our bodies. . The food we eat contains nutrients. Some of these we disassemble and then reassemble for parts we need. Some nutrients are essential because we can’t manufacture these on our own.

Organic macromolecules are the building blocks of life. They are all large molecules that all contain carbon. Carbon has 4 electrons in its outer shell. Therefore carbon can form up to 4 covalent bonds , usually with H, O , N, or C. Macromolecules come in 4 types. Carbohydrates Lipids Proteins Nucleic acids

CARBOHYDRATES All carbohydrates are made up of only 3 elements: C, H, O. All carbohydrates look like this in their simplest form (CH 2 O)n. This is a simple sugar: glucose (CH 2 O)6 Mono = one, saccharide = sugar. If you put two of them together you get a dissacharide. Di = two And if you string a bunch of monosaccharides together you get a polysaccharide. They look like this.

WHY ARE CARBOHYDRATES IMPORTANT? They are the body’s preferred choice of energy. Just like your favorite shirt, you could wear the other shirt, but this one fits over your head without tugging. Carbohydrates store and provide energy. In some organisms they provide structural support. Glycogen is important storage of energy in liver and muscles. It is broken down to glucose when the body needs energy between meal or when exercising WHAT FOODS CONTAIN CARBOHYDRATES?

Let’s review carbohydrates. Cornell questions Why do you need to eat them? What foods contain carbohydrates? List the 3 elements that are contained in carbohydrates. Which of the following is a polysaccharide?

LIPIDS Lipids contain 3 elements; C, H and a few O. Sounds familiar right! Lipids have fatty acid tails. Each tail is a chain of C atoms bonded to H or C by single or double bonds. If the tail have one single bond they are called saturated fats because no more H can bond to the tail. Fatty acid tails with at least one double bond are called unsaturated fats. More than two double bonds = poly unsaturated fats.

Lipids made from a gylcerol molecule and three fatty acids are trigylcerides. Triglycerides are fats and oils. Fat are solid at room temperature and oils are liquid at room temperature. Why are lipids important to our bodies? 1. Storage of energy. This way if you run low on carbs…. . 2. Thermal insulation. 3. Mechanical protection. Example surrounding delicate organs such as the heart. 4. Waterproofing. Like the wax in your ears.

A special type of lipids are called phospholipids. They look like this. They have 2 fatty acids and a glycerol. The also have an end that loves to be in water (hydrophilic) and a side that repels water(hydrophobic). Steroids are an important group of lipids that includes cholesterol and hormones. Many vitamins can only be delivered in a fat package Two layers together is a perfect way to surround a cell or a cell part to create a barrier!

Review time. Cornell Questions What 3 elements make up the group called lipids? Which of these are a lipid? How can you tell? List 3 ways your body uses lipids. What foods contain lipids?

PROTEINS Proteins are composed of 4 elements: C, H, O, and N. The basic unit (monomer) is called an amino acid and it looks like this. Four groups around a central carbon. One of those bonds is with a hydrogen. The other three bonds are with an amino group(-NH 2), a carboxyl group (-COOH), and a variable group R. Covalent bonds called peptide bonds form between the amino group of one and the carboxyl group of another. There are 20 different variable groups and proteins are made from combinations of all 20. This is a 3 -D image of a protein containing thousands of amino acids connected together & folded to make this distinct shape.

Based on the variable group, proteins can have up to four levels of structure: A. Primary Structure - Amino acids bonded together by peptide bonds (straight chains) B. Secondary Structure- 3 -dimensional folding arrangement of a primary structure into coils and pleats held together by hydrogen bonds, can result in helix structures or pleated sheets. C. Tertiary Structure – is globular like hemoglobin D. Quaternary Structure- proteins combining with proteins Six functions of proteins: 1. Storage: 2. Transport: 3. Regulatory: 4. Movement: 5. Structural: 6. Enzymes: albumin (egg white) hemoglobin hormones muscles membranes, hair, nails cellular reactions

WHY DO YOU NEED TO EAT PROTEINS? Proteins make up most of the structure of your body. Actually, by weight, you are mostly water with proteins in second place. These are muscle cells. This is someone with big muscles. Hair is also made up of protein. Proteins can be enzymes; these proteins regulate chemical reactions in your body.

Proteins also form some of the entrances and exits through the cell.

WHICH FOODS PROVIDE PROTEINS IN OUR DIET?

Review again? Of course!!!! 1. Which of the following suspects is a protein component? 2. List some foods that provide proteins? 3. How does my body use proteins?

NUCLEIC ACIDS Nucleic acids are complex macromolecules. They store and transmit genetic information from generation to generation(DNA) and are used to make proteins(RNA). Nucleic acids are made up of lots of nucleotides (the smallest units) strung together. DNA takes the shape of a double helix.

Two types: a. Deoxyribonucleic acid (DNA- double helix) b. Ribonucleic acid (RNA-single strand) Nucleic acids are composed of long chains of nucleotides Each nucleotide includes: phosphate group pentose sugar (5 -carbon) DNA uses the sugar deoxyribose RNA uses the sugar ribose. nitrogenous bases: adenine (A) thymine (T) DNA only uracil (U) RNA only cytosine (C) guanine (G) The nucleotides are joined by bonds between their sugar and phosphate group.

Nucleotide Phosphate Group O O=P-O O 5 CH 2 O N C 1 C 4 Sugar (deoxyribose) C 3 copyright cmassengale C 2 Nitrogenous base (A, G, C, or T) 20

DNA double helix O 5 3 P 5 3 O O C G 1 P 5 3 2 4 4 P 1 5 O T 5 P 2 3 A P 3 O 3 The nucleotides are joined by bonds between their sugar and phosphate group. O 5 P 21

Review again? Ofcourse (Cornell questions) • What is the function of DNA and RNA? • What is the structure of a nucleic acid?