A&P Review for Chapter 2: Chemical Basis of Life

Review for Chapter 2 Chemical Basis of Life 1. Isotope- 2 or more forms of the same element that contain an equal # of protons but different # of neutrons in their nuclei (differ in atomic mass). 2. Ion- an atom that gains or loses an electron to become stable. Electrically charged atom. 3. pH- The pH scale indicates the concentration of hydrogen ions in a solution. Determines if it is an acid or a base. pH depends on how a substance reacts in water. 4. Acid- the pH of less than 7 indicates a greater concentration of H than OH. An acid is an electrolyte that dissociates and releases hydrogen molecules. EXhydrochloric acid. 5. Hydroxide-an oxygen and hydrogen bond held together by a covalent bond. OH. basic. 6. Hydronium- a water molecule (h2o) that has gained an extra hydrogen atom. Cation. Very acidic. 7. What does chemistry study? Chemistry studies the composition of substances and how they change in chemical reactions. Human body, food, and medications are all composed of chemicals. All anatomical structures are chemicals and all physiological processes are based on chemical reactions. 8. What is an element? Simplest examples of matter with specific chemical properties. 9. What are the most abundant elements in the human body? CHONS CAP. (carbon, hydrogen, oxygen, nitrogen, sulfur. Calcium, and Phosphorus) 10. Know all the subatomic particles and their charge and where they are found? Protons- one positive charge, found in the nucleus. Neutrons- no electrical charge, found in the nucleus. Electrons- 1 negative charge, found in the outer shell and spin around the atom. 11. Atomic number indicates the number of….. The # of protons in the nucleus 12. Atomic weight indicates the number of….. The # of protons plus the # of neutrons 13. Know the different types of chemical reactions- occur when chemical bonds form or break between atoms, ions or molecules. Reactants- starting materials of a chemical reaction; the atoms, ions or molecules. Products- substances formed at the end of the chemical reactions. TYPES: Synthesis reaction- a more complex chemical structure is formed. A B AB. Decomposition reaction- chemical bonds are broken and new bonds are formed. AB A B. Exchange reaction- chemical bonds are broken and new bonds are formed. AB CD AD CB. Reversible reaction- the products can change back to the reactants. A B AB. 14. Know the 3 types of chemical bonds. Which one is the strongest? The weakest?Ionic Bonds- formed when electrons are transferred from one atom to another atom. The attraction between a cation (positive charge. When an atom loses electrons) and anion (negative charge. When an atom gains electrons) forms a very strong bond between the ions aka an ionic bond. Covalent Bond- strong chemical bonds formed between atoms that share electrons. STRONGEST. Commonly between the water molecule. Have to form a covalent bond with another hydrogen molecule and share the electron that makes hydrogen exist as H2 in the atmosphere. Same with oxygen it has a complete outer shell and doesn't really want to give up an electron so they covalently bond together and share the electron. Polar bond (hydrogen bond)- molecules with a slightly negative end and a slightly positive end. Results from unequal sharing of electrons in covalent bonds. Water is an important polar molecule. Bond that exists between hydrogen. Slight negative on the o2 side and pos on the hydrogen side. Which gives it it’s unique way to freeze and be liquid. Usually weak but water is a strong one. Important for protein and nucleic acid structure. 15. What does pH-scale measure? What is the pH of human blood?- measures the concentration of hydrogen ions in a solution. pH of human blood is 7.35-7.45. Human blood is slightly alkaline because you undergo changes constantly with cellular respiration so you are changing the hemodynamics of your blood and it starts to lower the pH and can slide down to neutral. 16. Know the 4 major classes of organic compounds and what we discussed about each (proteins, carbs, lipids and nucleic acids). - Carbohydrates- are the main source of cellular energy that is going to supply us with the building blocks we need in order to build cellular structures in our body. It is an organic substance. Water soluble. Contains C H AND O. Ratio of H to O close to 2:1. Monosaccharides single sugars like glucose. Disaccharides double sugars like lactose. Polysaccharides a complex carbohydrate like starch. Lipids- insoluble in water (hydrophobic) but soluble in organic solvents. Includes triglycerides (fats), phospholipids, steroids. Important component of cell membranes and have several functions in cells. Most abundant lipids are triglycerides; they are used for cellular energy and contain more energy per gram than carbohydrates. Contain C H AND O but less than carbs. Consist of 1 molecule of glycerol to 3 fatty acids. Proteins- are amino acids bound together through peptide bonds. There are 4 levels to the protein structure: Primary- amino acid sequence. Secondarypleated or twisted structure formed by hydrogen bonding between non adjacent amino acids. Tertiary- unique 3-dimensional folded shape of the protein. Quaternary- structure formed by some proteins, when 2 or more polypeptide chains are connected to become 1 protein. Nucleic acids- atoms that include carbon ,nitrogen, and phosphorus. Nucleic acids carry genetic code (DNA) or aid in protein synthesis (RNA). Nucleic acids encode amino acid sequences of proteins. Building blocks are called NUCLEOTIDES, which consist of a sigar(S), a phosphate group (P), and an organic base (B). 17. What does it mean by compound? Organic? Compound is a particle formed when 2 or more atoms (same or different) chemically combine. Organic molecules- contain carbon and hydrogen. Water soluble organic compounds do not release ions and are non- electrolytes. Inorganic- water, oxygen, co2, and inorganic salts. Usually dissolve in water and dissociate forming ions and are electrolytes 18. What are the different examples of proteins? What is an enzyme? What are the 3 types of lipids? 3 kinds of lipids- Triglycerides (fat). Phospholipids, and steroids. 1-4 structure types of proteins. An enzyme is a protein that speeds of th erate of a chemical reaction 19. What are the building blocks (monomers) of proteins, carbohydrates and nucleic acids? Carbohydrates are the building blocks 20. What determines how a protein is shaped and therefore how it functions? The structure of the peptide bonds 21. What are cell membranes made of? A phospholipid bilayer. 1 glycerol molecule to 3 fatty acids. Phospholipids and proteins. 22. What are the four levels of organization of a protein? 1. Primary, 2. Secondary, 3. Tertiary, 4. Quaternary