UNIT 2: Patterns in Living Systems SB1. Obtain, evaluate, and communicate information to analyze the nature of the relationships between structures and functions in living cells. Anchoring Phenomena:

SB1c. Construct arguments supported by evidence to relate the structure of macromolecules (carbohydrate, proteins, lipids, and nucleic acids) to their interactions in carrying out cellular process. Learning Targets: 2.1 I can describe the properties of carbon that allow it to form complex organic molecules. 2.2 I can use laboratory tests to identify the four types of macromolecules. 2.3 I can describe the structure, function, examples, and sources of carbohydrates, lipids, proteins, and nucleic acids. 2.4 I can describe how enzymes act as catalysts for biological reactions by lowering activation energy. 2.5 I can discuss three characteristics of enzymes: 1. affected by pH, temperature, and concentration 2. re-usable 3. substrate-specific 2.6 I can construct an argument supported by evidence relating the structures of macromolecules to their functions. 2.7 I can diagram and explain the ATP/ADP cycle.

Biochemical Compounds Living things depend on biochemical processes that involve chemical reactions among biochemical compounds. There are 4 main classes of biochemical compounds, or macromolecules are: Carbohydrates Proteins Lipids Nucleic Acids

Biochemical Compounds Study of chemical composition and reactions occurring in living matter Inorganic Compounds Do not contain carbon Exceptions - CO2, CO, bicarbonates Water is the most abundant and important inorganic material, making up 60% - 80% of all cells and 2/3 of body weight Identify the important facts regarding inorganic molecules.

Biochemical Compounds Although cells are 70-95% water, the rest consists mostly of carbon-based compounds, or organic compounds. Proteins, nucleic acids, carbohydrates, and lipids are all composed of carbon atoms bonded to each other and to atoms of other elements. These other elements commonly include hydrogen (H), oxygen (O), nitrogen (N), sulfur (S), and phosphorus (P).

Carbon atoms are the most versatile building blocks of molecules Biochemical Compounds Carbon atoms are the most versatile building blocks of molecules With a total of 6 electrons, a carbon atom has 2 in the first shell and 4 valence elections in the second shell. Carbon usually completes its valence shell (sharing a total of 8 elections) by sharing electrons with four other atoms in four covalent bonds.

Biochemical Compounds All macromolecules contain the elements carbon, hydrogen and oxygen. Carbon is found in things that are or once were living. Carbon atoms share electrons to form covalent bonds. As carbon-carbon bonds are broken, quick energy is released for use by the organism Have students differentiate between organic and inorganic compounds.

Biochemical Compounds Organic compounds are composed of hundreds to thousands of individual molecules. The single molecules in a polymer are called monomers. The images at the bottom are examples of monomers. Explain to the students that fructose is a simple sugar. The string of beads are also an example of monomers. As the beads are all the same in the string.

Biochemical Compounds The long molecules formed by repeating patterns of monomers are called polymers. Compare the structure of the monomers to the polymers. Use the InterWrite tablet to identify the bonds for students.

Carbohydrates Found in breads, pastas, and fruit Contain C,O, and H Examples: Sugars, Starches, and Cellulose Used as sources of energy for cells Some carbs give structure to living cells In plants, cellulose is a rigid material that gives support to plant cells

Carbohydrates: Monosaccharides The simplest type of carbohydrate Examples of monosaccharides: Glucose Galactose Fructose All of these are simple sugars Glucose

Carbohydrates: Dissacharides Two monosaccharides bonded together Example of a disaccharide Sucrose-glucose + fructose Sucrose is commonly known as table sugar

Carbohydrates: Polysaccharides Chains of Monosaccharides covalently bonded. Examples Starch Cellulose Glycogen

Lipids Examples: Fats and oils Organic molecules that do not dissolve or break apart in water Found as fats in animals and oil in plants Store energy from excess food and insulates and waterproofs organisms

Lipids Lipids Many lipids are formed from a combination of one glycerol molecule and three fatty acid molecules Consist of C, H, and O Saturated-if each carbon atom in the fatty acid chains is joined to another carbon by a single bond Unsaturated-if there is at least one double bond between carbon atoms

Lipids: Phospholipid Bilayer Phospholipids are a key part of plasma membranes, making them semipermeable -Nonpolar molecules can pass directly through the lipid bilayer. -Polar molecules must pass through by other means.

Proteins Organic molecules composed of many atoms of C, H, O, and N Made of building blocks called amino acids Amino acid- carbon compound whose molecule contains at least one amino group (-NH2) and one carboxyl group (-COOH)

Proteins Amino acids join together to form chains called polypeptides. There are 20 different amino acids The amino group of one amino acid bonds to the carboxyl group of another The bond that holds two amino acids together is called a peptide bond

Proteins When two amino acids bond together, they form a dipeptide Additional amino acids may join with a dipeptide to form a polypeptide

Proteins The sequence and arrangement of amino acids determines the specific role of the protein Functional Take part in chemical reactions and transporting materials (hormones, such as insulin, and catalysts such as enzymes) Structural Serve as building blocks (Collagen-forms bones, tendons, ligaments, and cartilage)

Proteins: Enzymes Enzymes are organic catalysts that control the rate of chemical reactions within cells. A single organism may possess thousands of different enzymes. Each one is specific to a certain chemical reaction. Enzymes have a specific shape, called the active site, to which the reactant, or substrate can attach.

Proteins: Enzymes By providing such a reaction site, enzymes reduce the amount of energy that substrates need to react. In other words, enzymes reduce the ACTIVATION ENERGY

Proteins: Enzymes Three factors affect enzyme activity: Temperature pH Enzymes from different organisms tend to work best at different optimum temperatures. pH The pH of a solution describes how acidic or basic the solution is. Most enzymes function in a very narrow pH range, which varies depending on the enzyme and its job. Concentration The more substrate molecules available, the faster the reaction rate until saturation.

Nucleic Acids The information that is passed on from one generation of cells to the next-genetic information- is stored in nucleic acids Made of C,H,O,N, and P Nucleic acids are assembled from individual units called nucleotides Two Most important nucleic acids: DNA (Deoxyribonucleic acid) RNA (Ribonucleic acid)

Nucleic Acids Genetic information is stored in DNA. It is TRANSCRIBED into RNA, and then TRANSLATED, or used to direct the production of PROTEINS!

Nucleic Acids: ATP/ADP In living things energy is stored in a molecule of adenosine triphosphate (ATP) WHAT IS RIBOSE???

Nucleic Acids: ATP/ADP Energy is stored in chemical bonds between phosphates Energy is released when the bond is broken and one phosphate is released Adenosine diphosphate (ADP) is produced when the phosphate is released

phosphate removed