KEY CONCEPT Carbon-based molecules are the foundation of life.

Draw a mark at the midpoint of a sheet of paper along the side edge. Then fold the top and bottom edges in to touch the midpoint.

Fold in half from side to side.

Open and cut along the inside fold lines to form four tabs.

Label each tab.

As you read Section 2.3, draw the structure and list the characteristics of carbohydrates, lipids, proteins, and nucleic acids under the appropriate tabs.

Elements of Life 96% of living organisms are made of: carbon (C) oxygen (O) hydrogen (H) nitrogen (N) 3

Put C, H, O, N together in different ways to build living organisms Molecules of Life Put C, H, O, N together in different ways to build living organisms What are bodies made of? carbohydrates sugars & starches proteins fats (lipids) nucleic acids DNA, RNA 4

organic molecules Water 65% of your body is H2O water is inorganic Don’t forget water Water 65% of your body is H2O water is inorganic doesn’t contain carbon Rest of you is made of carbon molecules organic molecules carbohydrates proteins fats nucleic acids 5

Carbon atoms have unique bonding properties. Carbon forms covalent bonds with up to four other atoms, including other carbon atoms. Carbon-based molecules have three general types of structures. straight chain branched chain ring 6

Many carbon-based molecules are made of many small subunits bonded together. Monomers are the individual subunits. Polymers are made of many monomers. DRAW ME! Monomer—small molecule that is a single unit in a much larger molecule Polymer—large molecule (macromolecule) formed from many monomers bonded together 7

Four main types of carbon-based molecules are found in living things. Carbohydrates are made of carbon, hydrogen, and oxygen. 8

Four main types of carbon-based molecules are found in living things. Carbohydrates are made of carbon, hydrogen, and oxygen. Carbohydrates include sugars and starches. Monosaccharides are simple sugars.(monomer) Polysaccharides include starches, cellulose, and glycogen. (polymer) Monomer—glucose Demo Dehydration of Sucrose. C12H22O11(s) + H2SO4 = 12C + 11 H2O 9

Carbohydrates can be broken down to provide energy for cells. Some carbohydrates are part of cell structure. Polymer (starch) Starch is a polymer of glucose monomers that often has a branched structure. Polymer (cellulose) Cellulose is a polymer of glucose monomers that has a straight, rigid structure monomer Monomer—glucose 1. Functions—broken down to provide a source of energy; make up plant cell walls 10

Many contain carbon chains called fatty acids. Lipids are nonpolar molecules that include fats, oils, and cholesterol. Many contain carbon chains called fatty acids. Fats and oils contain fatty acids bonded to glycerol. Triglyceride 11

Lipids have several different functions. broken down as a source of energy make up cell membranes used to make hormones Functions—broken down to provide a source of energy; make up cell membranes; used to make steroid hormones 12

Fats and oils have different types of fatty acids. saturated fatty acids unsaturated fatty acids 13

Phospholipids make up all cell membranes. Polar phosphate “head” Nonpolar fatty acid “tails” Phospholipid Molecule—phospholipid; phosphate group head; nonpolar fatty acid tails 14

Proteins are polymers of amino acid monomers. Twenty different amino acids are used to build proteins in organisms. 15

Proteins are polymers of amino acid monomers. Twenty different amino acids are used to build proteins in organisms. Amino acids differ in side groups, or R groups. 16

Proteins are polymers of amino acid monomers. Twenty different amino acids are used to build proteins in organisms. Amino acids differ in side groups, or R groups. Amino acids are linked by peptide bonds. 17

Proteins differ in the number and order of amino acids. Amino acids interact to give a protein its shape. hydrogen bond Hemoglobin Incorrect amino acids change a protein’s structure and function. 18

Hemoglobin in red blood cells transports oxygen Hemoglobin in red blood cells transports oxygen. The structure of hemoglobin depends on hydrogen bonds between specific amino acids. Just one amino acid change causes red blood cells to have the curved shape characteristic of sickle cell anemia. (colored SEM; magnification 3500 X)

Functions of proteins Functions—many, including enzymes, oxygen transport, and muscle movement Functions—many, including enzymes, oxygen transport, and muscle movement

Nucleic acids are polymers of monomers called nucleotides. 20

DRAW ME! Nucleic acids are polymers of monomers called nucleotides. Nucleotides are made of a sugar, phosphate group, and a nitrogen base. A phosphate group nitrogen-containing molecule, called a base deoxyribose (sugar) DRAW ME! 21

Nucleic acids are polymers of monomers called nucleotides. Nucleotides are made of a sugar, phosphate group, and a nitrogen base. DNA stores genetic information. DNA RNA builds proteins. RNA 22

Reteach - Identifying Variables - SC. 912. N.1.1 A scientist studied the effect of jogging on the number of Calories used. People jogged for three different lengths of time - 10 minutes, 20 minutes, 30 minutes. The number of Calories used was measured, recorded, and plotted on a bar graph. What are the independent variables? What are the dependent variables? Independent- length of time spent jogging Dependent- number of Calories used. 23

Review To reinforce the concept of polymers(many) made from repeating monomers(one). Complete the following chart: Monomer Polymer

Check your answers To reinforce the concept of polymers(many) made from repeating monomers(one). Complete the following chart: Monomer- (subunits) Polymer (macro molecules) Monosaccharide (simple sugars) polysaccharides starches- cellulose Amino acids proteins Nucleotides nucleic acids Fatty acids lipids(triglycerides) Lipids are smaller than true polymers and are not made of repeating units. Monosaccharides (simple sugars) -- polysaccharides starches-cellulose Amino acids proteins Nucleotides nucleic acids Fatty acids lipids(triglycerides) 24