Atoms & Life Substances Section 6.1 & 6.3 Take 2 minutes and brainstorm with your lab partner at least 3 concepts you think will be discussed looking at the title above.

Atomic Structure 6.1  Nucleus = center of an atom, contains protons (p+ positively charged) and neutrons (nº neutral)  Electrons (eˉ) are negatively charged particles that surround the nucleus  Atoms are neutral because they contain equal numbers of protons and electrons

Biomolecules (6.3)  These are the molecules required by living things  1. Carbohydrates  2. Proteins  3. Lipids  4. Nucleic Acids (There are other types of molecules too!!!)

 Organic Compounds = contain carbon, all biomolecules are organic  Monomer = a building block, smaller subunits  Polymer = made up of lots of monomer subunits

1.CARBOHYDRATES pg. 158  Source of energy  Structural materials  Monosaccharides & Polysaccharides

Monosaccharide Carbs  They’re Monomers =1 Carbohydrate  Glucose = main source of energy for cells, diabetics need to monitor glucose levels

Polysaccharide Carbs  Polysaccharide = 3 or more monosaccharides  Glycogen = how animals store glucose  Starch = how plants store glucose  Cellulose = polysaccharide, provides plants with structure

2. PROTEINS pg. 161  Hair, horns, nails, skin, muscle  Act as biological catalysts (enyzmes) which help to kick start reactions in the body

Amino Acids  Protein monomer  20 different amino acids  Peptide Bond = connects amino acids  html html html  Polypeptide = long chain of amino acids

Enzymes  Enzymes change the rate of reactions in the body  Help cells reproduce, digest food, get rid of waste, make new biomolecules  Active Site = a section of the enzyme shaped to fit a specific substrate  Substrate = something that’s being broken apart or made (catalyzed)  y.html y.html y.html  hill.com/sites/ /student_view0/chapter2/animation__how_enzymes _work.html hill.com/sites/ /student_view0/chapter2/animation__how_enzymes _work.html hill.com/sites/ /student_view0/chapter2/animation__how_enzymes _work.html

3. LIPIDS pg. 160  Insoluble = Don’t dissolve in water  Best for storing energy  Insulation, protective coverings  Major part of cell membranes 

Saturated & Unsaturated Fats  Saturated Fat = found in butter, red meat (solid at room temperature), saturated with hydrogen  Unsaturated Fat = vegetable fats (liquid at room temperature)

Phospholipids  Cell membranes made up of two layers of phospholipids, forms a barrier  Keeps things that are supposed to be out, out of the cell  Keeps things that are supposed to be in, in the cell  2 fatty acids attached to glycerol, and a phosphate group Phosphate Lipids

Practice  What percent of your body is made of water?  Explain why a cell needs a structure that helps it maintain water levels inside? What could happen to the cell if this structure wasn’t working properly?

Other types of LIPIDS besides fats…  Wax  Structural  Makes a coat on plants for water proofing  Steroids  Hormones that cause physical changes in the body

4. NUCLEIC ACIDS pg. 163  Store and transfer info in the cell  Nucleotide = monomer of nucleic acids  2 kinds of nucleic acid polymers:  DNA = deoxyribonucleic acid  RNA = ribonucleic acid