Chapter 2 CHEMISTRY – RAW MATERIALS AND FUEL FOR OUR BODIES Learning Objectives: Relate major principles of chemistry to the study of biology Understand atomic structure Compare and contrast the major chemical bonds involved in important molecules and compounds Identify the major macromolecules that make up living organisms Explain the importance of the function of each of the four major macromolecules Describe the different categories of carbohydrates and their uses Compare and contrast different categories of lipids and their structures Understand the importance of shape in the functioning of a protein Compare and contrast DNA and RNA Chapter Outline I. Atoms Form Molecules through Bonding A. Understanding chemistry is essential to the study of biology. Learning about chemistry allows us to understand the necessary building blocks of important molecules and the chemical reactions that help power a cell Long regarded as precious, gold has always been evaluated for its beauty and value. However, when evaluating gold for its chemical makeup, gold is an example of an _______________________, or a substance that cannot be broken down further into any other substance. Atomic Structure Describe the relationship between an atom and an element The individual particles or pieces that form the structure of an atom have unique characteristics. Complete the following chart to highlight the particles that form the structure of an atom. Particle Type Charge Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies o Which two parts make up the nucleus of the atom? Define the atomic mass of an atom o Do electrons contribute to the overall mass of the atom? Explain. Carbon has an atomic number of six. This number refers to the number of ________________ carbon has. Will any other atom of a different element have the same number? Explain. There are many different naturally occurring elements. When examining the human body, we find we are composed of 25 different elements. Of those 25, only four elements make up approximate 96% of us! List the “Big 4” here. 1. 2. 3. 4. B. Atom’s Electron Shells ____________________________ determines how and if an atom will bond with other atoms. Because the aforementioned particle carries a negative charge, there is a limit to the number that move around the nucleus of the atom together, or in the same electron shell o The atom’s first electron shell, which is innermost and closest to the nucleus, can hold _____ electrons. o The second and subsequent shells can hold more, or up to ______ electrons Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies Draw the appropriate umber of electron shells and the appropriate number of electrons in each shell for carbon. The nucleus of the atom is below. (Hint: Carbon has six electrons) © Explain why the atom is stable when the outermost electron shell is full? o What happens if the outermost shell is empty? C. In your own words, briefly describe what an atom has to do to become an ion Chemical Bonding A molecule is a group of _______________________ held together by _______________ What determines the type of bond that will form between reactive atoms? Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies Types of bonds – Describe how each bond holds atoms or groups of atoms together and list an example: 1. Covalent bond: 2. Ionic bond: 3. Hydrogen bond: D. Consequences of a Molecule’s Shape What determines the shape of a molecule? Use an example. What two important senses are impacted by the variation in shape of different molecules? Explain why, Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies II. Water Has Features That Enable It to Support All Life A. B. Water Molecule Properties and the Hydrogen Bond Explain the term polar molecule, how organisms such as the Jesus Lizard can take advantage of surface tension and walk across water. Properties of Water Make it Critical to Life List the four important properties of water and then explain how the feature is essential for living organisms. 1. 2. 3. 4. C. Acids, Bases, and pH A water molecule can be broken apart releasing ______________ and _____________ ions These ions individually can affect the pH of a particular solution. The pH scale measures: ________________________________________________________________________ A fluid with a pH between 0 and 6.9 would be considered _____________________ and has more H+ or OH- ions? A fluid with a pH between 7.1 and 14 would be considered _____________ and has more H+ or OH- ions? Give your own example of a food or household item that would register as an acid on the pH scale. Give an example of an item that would register as basic. Explain what happens to a solution when you add a buffer. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies III. Carbohydrates are Fuel for Living Machines A macromolecule can be simply defined as: The four major types of macromolecules that are necessary for our cells include: 1. 2. 3. 4. Carbohydrates a. Carbohydrates are made up of the three following elements: i. ii. iii. b. All carbohydrates are found with similar composition of an H2O unit for every carbon. Give the chemical formula for glucose: __________________ c. What is the primary function of carbohydrates in our cells? i. Explain why carbohydrates are so well-suited for this function. A. Monosaccharides Monosaccharides are also called ________________________. Give an example of a monosaccharide with which you are familiar with. The glucose from fruit, bread, potatoes, and other carbohydrate sources ends up in the bloodstream. There are then several potential end results for the glucose circulating in the blood. Explain the three potential fates: Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies What is glycogen’s role in “carbo-loading”? What does “water weight” have to do with glycogen? B. Complex Carbohydrates Complex carbohydrates are a source of fuel containing more than one sugar building block. These include: A. ___________________________, which are two monosaccharides linked together and, B. ___________________________, which are many monosaccharides (even thousands) linked together. Disaccharides A. Give an example of a disaccharide and explain how it is utilized for fuel Polysaccharides A. What is the function of starch in plants? B. What is the function of glycogen in humans? There are unique polysaccharides that are indigestible by humans but can serve as structural material for various organisms. Give an example of where each of the following are found: A. Chitin: B. Cellulose 1. Why is cellulose an important part of the human diet even though humans cannot digest it? Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies IV. Lipids Store Energy for a Rainy Day Lipids are a large, diverse group of macromolecules with important functions. Like other macromolecules, the structure of lipids includes the elements C, O, and H, but lipids have a higher ratio of C-H bonds. How does this affect lipids? Some important properties of lipids include how they behave in water. Define: o Hydrophobic o Hydrophillic List three types of lipids and their function 1. 2. 3. A. Fats The fats were are concerned about in the foods we eat are also called: ____________________ List the parts of the structure of a triglyceride and label these parts on the symbol below. Explain the structural difference between a saturated fat and an unsaturated fat. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies What is a favorite food of yours that is high in saturated fats? What is a favorite food of yours that is high in unsaturated fats? Olestra is a fat substitute. It is found in many food products, such as potato chips, that strive to reduce the fat content in order to make the product more appealing to consumers. o What is the chemical structure of olestra? o Are there consequences associated with a diet high in olestra? Explain. B. Sterols What is the basic structure of all sterols? List two important examples C. Phospholipids Draw the basic structure of a phospholipid This category of lipids plays an important role in the cell’s ___________________________. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies V. Proteins are Body-Building Molecules A. Proteins are the most diverse group of macromolecules and function to regulate cellular activity, provide support, and assist in chemical reactions. Protein Structure Proteins are similar to carbohydrates and lipids as they also contain C, O, and H, but they can be distinguished from these other important macromolecules because they contain ____. Despite the large variety of proteins found, they are all composed of the same building blocks. By connecting different ____________________ together, the result is a unique protein. There are ______ different amino acids available, just as there are 26 letters in our alphabet to select from when writing different words. Structure of an amino acid o Identify three main groups that form the structure of the amino acid. o What makes one amino acid different from another? B. Protein in Your Diet Our cells require amino acids for various cellular structures and activities. Cells can make some of the amino acids that are required, but not all of them. Other necessary amino acids are obtained through the diet. The amino acids we must be certain to include in our diet are called _______________________________________. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies C. Briefly describe the difference between a complete protein and an incomplete protein. Protein Shape Cells will build protein by linking amino acids together by a ______________________ bond. The order of the amino acids as well as the overall structure the protein takes on impacts how that protein functions. The possible shapes, or structure, of proteins are: 1. 2. 3. 4. If at any time, something alters the shape of the protein, the protein will no longer be able to function properly. That, in turn, can affect cellular functioning. When a protein is exposed to an extreme environment, such as high temperature or changes in pH, what is the term that is used to describe what has occurred? ________________________ D. Enzymes One important class of proteins is enzymes. Briefly explain what an enzyme’s job is and if they can perform their job more than once. Only specific substrates can fit in an enzyme’s _________________ site to catalyze a reaction. Explain why disease or disorder could result from an enzyme that isn’t formed properly. Include an example. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies VI. Nucleic Acids Store the Information on How to Build and Run a Body A. The fourth major category of important macromolecules is nucleic acids. Two types of nucleic acids are: 1. 2. The building blocks for nucleic acids are __________________________. A nucleotide is made up of three parts: 1. 2. 3. Each nucleotide can contain one of ____________ different bases. These bases include: 1. 2. 3. DNA Briefly explain the job of DNA in producing proteins. Many nucleotides link together to create a strand of DNA. One strand of DNA is bound to a second strand of DNA by __________________ bonds. These two strands then spiral around each other forming the structure of DNA known as a __________________________. It is often easier to draw SNA as if it were a ladder. The vertical uprights of the latter would include the ________________________ and _________________________. The rungs of the ladder, or where you would place your foot if you were climbing the ladder would be the _________________________________. If you were to examine the structure of DNA in great detail you would start to notice a pattern in which DNA bases were connected, or how one strand of DNA was bound to the second strand of DNA. Explain which bases always pair together. B. RNA Briefly explain the job of RNA in producing proteins. There are three major differences between DNA and RNA. List the ways RNA is unique: 1. 2. 3. Chapter 2: Chemistry: Raw Materials and Fuel For Our Bodies