Anatomy and Phisology PP

3. Periodic Table of the Elements

8. Ionic Bonds – when an atom loses or gains one or more electrons, it becomes positively or negatively charged – an ION. A positive ion is called a CATION and a negative ion is called an ANION. Sodium (Na) has 11 e, only one in the outer shell, so it tends to be an electron DONOR. Chlorine (Cl) has 17 e, and its outer shell has 7 e, so it tends to be an electron ACCEPTOR. When a Na atom and a Cl atom come together, an electron is transferred from the Na atom to the Cl atom. Now both have 8 e in their outer shell.

9. Covalent Bond – when two atoms share one or more pairs of electrons this called a covalent bond. E.g., H has 1 e in the outer shell so it can accept 1 more e. A H atom can share with another H atom. Because they share the electron pair, each atom has a completed outer shell. H—H or H 2.

10. Oxygen – oxygen has 6 electrons in the outer shell, so atoms share 2 electrons to make a total of 8 electrons. Thus a double covalent bond. Nitrogen – nitrogen has 5 electrons in the outer shell so atoms share 3 electrons to make a total of 8 electrons. Thus, a triple covalent bond.

13. Comparison of Ionic, Polar Covalent, and Nonpolar Covalent Bonds

15. Oxidation-Reduction Reactions Oxidation – the reactant losing the electrons is referred to as the electron donor and is said to be oxidized. Reduction – the reactant taking up the transferred electrons is called the electron acceptor and is said to become reduced. Redox reactions occur when ionic compounds are formed. E.g., NaCl – Na is oxidized and Cl is reduced E.g., Cellular Respiration………… C 6 H 12 O 6 + 6O 2 > 6CO 2 + 6H 2 O + ATP Glucose + Oxygen > Carbon Dioxide + Water + Energy Glucose is oxidized to carbon dioxide (loses H atoms) and oxygen is reduced to water (accepts H atoms)

19. Salts – an ionic compound containing cations other than H + and anions other than the hydroxyl ion (OH - ). When salts are dissolved in water, they dissociate into their component ions. E.g., NaCl + water > Na + and Cl - . All ions are electrolytes, substances that conduct an electrical current in solution ACIDS and BASES Acids – a substance that releases hydrogen ions (H + ) and anions when dissolved in water; they are called proton donors; HCL  H + Cl - ; H 2 CO 3 -  HCO 3 - + H + Bases – a substance that releases hydroxyl ions (OH - ) and cations when dissolved in water; they are called proton acceptors; NaOH  Na + + OH -

20. pH: Acid-Base Concentration The more H + ions in a solution, the more acidic the solution is. The more OH - ions, the more basic or alkaline the solution is. pH units measure the concentration of H + ions. The pH scale runs from 0 – 14 and is logarithmic, i.e., each successive change of one pH unit represents a tenfold change in H + concentration.

21. Buffers Homeostasis of acid-base balance is carefully regulated by the kidneys and lungs and by chemical systems called BUFFERS. Buffers help prevent large shifts of pH in the body fluids Strong Acids – acids that dissociate completely and irreversibly in water and they can change the pH of a solution. E.g., HCl; 100 HCl molecules + 1 ml water > 100 H+ and 100 Cl- Weak Acids – acids that do not completely dissociate. E.g., H 2 CO 3 ; 100 H 2 CO 3 + 1 ml water > 90 H 2 CO 3 + 10 H + + 10 HCO 3 Strong Bases – bases that dissociate easily in water and quickly tie up H + Weak Bases – bases that do not dissociate easily in water and accepts relatively few protons

24. Carbohydrates

32. Structural Levels of Proteins Primary – linear sequence of AA composing the polypeptide chain Secondary – twist or bend upon themselves to form a more complex structure ; alpha or beta Tertiary – 3d shape of a polypeptide chain; unique for each protein Quaternary – describes the arrangement of the individual polypeptide chains and how they bond

34. Enzyme Action Active site Amino acids Enzyme (E) Enzyme-substrate complex (E-S) Internal rearrangements leading to catalysis Dipeptide product (P) Free enzyme (E) Substrates (S) Peptide bond H 2 O +

35. Protein Denaturation In hostile environments (temperature, pH) lose shape (secondary, tertiary and quaternary) When a protein is subjected to extremes (e.g., pH drops or temperature rises above normal) the protein will unfold and lose their specific 3d structure. The protein is said to have been DENATURED. In some cases, process is reversible. In extreme cases, the protein is said to have been irreversibly denatured. Example: egg (albumin is a protein that makes up the “white” of the egg)….uncooked the white is actually clear when you cook the egg (temperature rises above normal) the albumin is denatured (changes the color and the structural arrangement of the protein)

37. DNA Molecule

38. DNA Molecule

39. Adenosine triphosphate (ATP) – adenine-containing RNA nucleotide which have 2 additional phosphate groups ATP

40. How ATP drives cellular work