Chemistry Of the Human Being

1. Chemistry Of the Human Being Part 1: Organization of the Human Body

2. Types of Chemistry • Inorganic Chemistry: Deals with substances that aren’t based upon carbon molecules. • Also known as General Chemistry • Organic Chemistry: Deals with substances produced naturally by plants and animals and contain carbon.

3. Organic Molecules • Basis of human structure and function. • 4 Primary Categories: • Carbohydrates • Lipids • Proteins • Nucleic Acid

4. Chemical Elements • Chemical Element: The simplest form of matter with its own unique chemical properties that cannot be broken down by ordinary chemical means. • 112 known elements • 92 occurring naturally • Each element is made up of atoms (which are combinations of protons, neutrons, and electrons).

5. Chemical Element Structures • Central Nucleus • Protons (+ charge) • Neutrons (no charge) • Ps & Ns in equal numbers • Electrons: (- charge) • Electron Shells • 1st Shell: 2 Electrons • 2nd Shell: 8 Electrons • 3rd Shell & Beyond: 18 Electrons

6. Periodic Table Information • Atomic Number: The number of protons (same as neutrons). • Atomic Mass: The number of protons plus the number of neutrons in the atom. • Isotopes: Contain a different number of neutrons than protons. This doesn’t change the charge of the atom.

9. Chemical Elements in the Human Body • 24 elements important for human physiology • 6 of these account of 98.5% of the human body’s total weight. • Oxygen • Carbon • Hydrogen • Nitrogen • Calcium • Phosphorus

10. Ions • Ion: Charged particle with unequal numbers of protons and electrons. • Gains or loses electrons & develop an electronic charge. • Cation: A particle that looses electrons and has a net positive charge. Ex. Na+ (sodium) • Anion: A particle that gains an electron to develop a net negative charge. Ex. Cl- (chloride)

11. Ions in the Human Body • 4 Ions essential to human physiology • Sodium: Na+ • Chloride: CL • Potassium: K+ • Calcium: Ca++

12. Combinations • Molecules: Chemical particles composed of two or more atoms. • Atoms united by covalent bonding (sharing an electron pair). • Atoms can be the same (O2) or different (CO2). • Compounds: Composed of atoms of two or more different elements. • Examples: Water (H2O), Sodium Chloride (NaCL)

13. Free Radicals • Charged groups of atoms with an odd number of electrons. • Unstable and quick to combine with fats, proteins and DNA. • Converts these into more free radicals which trigger chain reactions that destroy nearby molecules. • Produced by… • Some normal metabolic reactions of the body • Radiation (including ultraviolet light and x-rays) • Harmful chemicals (tetrachloride cleaning solvent)

14. Antioxidants • Antioxidants combat the chemical damage of free radicals by neutralizing their chemical reactions. • Examples: • Vitamin E, Selenium, Vitamin C • Free Radicals have been linked to cancer, diabetes, arthritis, Alzheimer’s, and more.

15. Bonding • Bonds: How atoms are held together to form compounds and molecules. • Chance of bonding depends on number of electrons in the valence (outer) shell. Atoms prefer to have 8 electrons in the valence shell. • Octet Rule: Atoms that have 8 electrons in the valence shell are les likely to bond.

16. 3 Basic Types of Bonds • Ionic Bond: Relatively weak attraction between an Anion and Cation. • Covalent Bond: Much stronger bond consisting of one or more shared electron pairs. • Nonpolar Bond: Shares the electrons equally. • Polar Bond: Shares the electrons uneqyally. • Hydrogen Bond: A weak attraction between a hydrogen atom with a partial positive charge and a neighboring atom with a partial negative charge. Best example is water.

18. Inorganic & Organic Compounds • Inorganic Compounds: A compound that does not contain carbon. • The most important compound (essential for life) is H20! • Organic Compounds: A compound that contains carbon.

19. Inorganic Compounds • H20 is an important Inorganic compound due to it’s… • Solvency: The ability to dissolve solutes (other chemicals). • H20 known as a universal solvent because of its high number of dissolvable solutes. • Cohesion: The tendency of molecules of the same substance to cling to each other. • This causes the surface film of water known as surface tension.

20. Inorganic Compounds • H20 is an important Inorganic compound due to it’s… • Chemical Reactivity: The ability of water to participate in a wide variety of chemical reactions. • Hydrolysis reactions add water molecules to decompose compounds. • Dehydration removes water molecules to add small molecules together. • Thermal Stability: Water helps stabilize the internal temperature of the body. • Water has a high heat capacity so can absorb or release large amounts of heat without changing its own temperature a whole lot.

21. Organic Compounds • Carbohydrates • Monosaccharides • Disaccharides • Polysaccharides • Triglycerides • Fatty Acids • Phospholypids • Eicosanoid • Steroids • Proteins

22. Carbohydrates • Hydrophilic (water-loving) • Organic (contain carbon) • Main source of energy production for cellular chemical reactions • ATP • Typically have sacchar root word or ose as a suffix. • Composed of 2:1 ratio of hydrogen to oxygen with carbon added in

23. Monosaccharides • Simple sugars composed of a single carbon containing molecule. • Includes: • Glucose (main blood sugar) • Fructose (fruit) • Galactose (milk)

24. Disaccharides • Simple sugars composed of 2 monosaccharide molecules. • Includes: • Sucrose (glucose + fructose; table sugar) • Lactose (glucose + galactose; milk) • Maltose (two glucose chains)

25. Polysaccharides • Complex sugars made of many monosaccharide molecules. • Glycogen: Energy-storage polysaccharide in animals, stored in muscles and liver. • Produced by the liver after a meal and when blood glucose is high. • Liver breaks it down when blood glucose is low to maintain homeostasis.

26. Polysaccharides • Lipids: Organic, hydrophobic (won’t dissolve in polar solvents like water); composed of carbon, hydrogen, and oxygen. • Function as a source of stored energy & components of cell structures. • Much more variable in structure than other macromolecules. • Primary function to store energy. • Provide thermal insulation • Act as a shock-absorbing cushion for organs • 4 Primary Lipids in humans: Triglycerides, phospholipids, eicosanoids, & steroids.

27. Lipids Important to the Human Body • Triglycerides: Most common lipid in the body & the diet; stored as adipose tissue. • Consists of 3 fatty acids attached to glycerol. • Fatty Acids: • Saturated: Full of hydrogen with a single bond between carbon atoms; sold at room temperature. • Unsaturated: Room for hydrogen with double bonds between carbon atoms; liquid at room temperature • Polyunsaturated: More than one double covalent bond between carbon atoms. • Monounsaturated: One double bond between atoms. • Nonessential Fatty Acids: Can be synthesized by the human body • Essential Fatty Acids: Must be obtained from the diet.

28. Lipids Important to the Human Body • Phospholipids: Any lipid containing phosphorus, including those with a backbone (base) or glycerol or sphingosine. • The major lipid in cell membranes. • Eicosanoids: Any physiologically active substance derived from arachidonic acid. • Includes Eprostaglandins. • Along with prostaglandins, plays an important role in inflammation, blood clotting, hormone action, labor contractions, and control of blood pressure.

29. Lipids Important to the Human Body • Steroids: Lipids composed of 4 rings of carbon atoms and include cholesterol. • Cholesterol is necessary for human life & is a building block molecule for all sex hormones, adrenalin, and is an essential cell membrane component.

30. Proteins • Proteins: “Proteios” is Greek for “of first importance.” • Most versatile molecules in the body • Structural component of cells and tissue • Are polymers (large molecules) of building blocks called amino acids joined by peptide bonds. • Composed of carbon, hydrogen, oxygen, nitrogen • Proteins have complex coiled and folded structures critically important to their function. Even slight changes can destroy or change protein function.

31. Proteins • 4 Basic structural Formations: • Primary: Sequence of amino acids in polypeptide chain (10-2000 amino acids joined together) • Secondary: Two neighboring polypeptide chains held together by hydrogen bonds. • Tertiary: 3-dimensional shape of a polypeptide chain • Quaternary: Arrangement of 2 or more polypeptide chains in relation to each other.

32. Proteins • Proteins have more diverse functions than other macromolecules, including… • Structural: Keratin, elastin, and collagen provide structural support • Regulatory: Many hormones and neurotransmitters regulate important body functions • Catalysis: Most metabolic pathways of the body are controlled by enzymes that function as catalysts • Immunity: I.e., antibodies • Contractile: Allow muscle to shorten and produce movement (actin & myosin)

33. Mixtures • Mixtures: Consists of substances that are physically blended together but NOT chemically combined. • The chemicals mixed retain their own chemical properties. • Can be Solutions, Colloids, or Suspensions

34. Characteristics of Solutions • Dissolved solutes • Mixed with an abundant solvent (such as water) • Solvent is transparent • Small particle size • Solute evenly dispersed within solvent

35. Characteristics of Colloids • Mixture typically cloudy (opaque) • Particles less than 100 nm • Particles suspended but not dissolved • Particles typically small enough to remain permanently mixed with the solvent so they don’t settle • Most common colloid in the body is protein • Examples albumin in blood • Milk is a colloid due to large proteins

36. Characteristics of Suspension • Suspended particles larger than 100 nm • Particle size causes suspension to be cloudy • Particles too heavy to remain permanently suspended (will separate on standing) • Example: Blood is a suspension of plasma and blood cells

37. Acids & Bases: pH • pH scale: • Ranges from 0 to 14 • Denotes the level of Hydrogen ions (H+) & Hydroxide ions (OH-) in a solution. • An equal number of H+ and OH- particles is a neutral pH level of “7”. • Acidic: More H+ than OH- (pH less than 7) • Alkaline: More OH- than H+ (pH more than 7)

38. pH in the Human Body • Blood has a normal pH of 7.35 to 7.45 • Acidosis: pH below 7.35 • Alkalosis: pH above 7.45

39. Work & Energy • Energy & Work are the process of breaking old bonds (releasing energy) and forming new bonds (requiring energy). • All activities by the body require energy! • Four main types of energy are… • Potential energy • Kinetic Energy • Chemical Energy • Activation Energy

40. Potential Energy • Potential energy: Energy stored by matter because of its position or internal state. • Is NOT doing work at this point in time.

41. Kinetic Energy • Kinetic energy: Energy of motion. • Example: Heat! • Heat occurs because of molecular activity/motion. • The more activity/motion occurs, the more heat is generated.

42. Chemical Energy • Chemical Energy: Potential energy stored in the chemical bonds of molecules. • Found in all molecules sharing a bond.

43. Activation Energy • Activation Energy: The amount of energy needed to allow an atom or molecule to collide with another and cause a disturbance of their valence electrons. • Is influenced by amount of particles and the environmental temperature. • The more particles & the higher the temperature, the more likely a collision & resulting chemical reaction is.

44. Activation Energy • The amount of particles in the body and the normal temperature are not high enough to trigger a life-sustaining rate of chemical reactions. • Catalysts: Substances that speed up the rate of chemical reactions in the body by lowering the amount of activation energy needed to start the reactions. • Do not alter the reactants or the products of the chemical reaction. • Enzymes used as a catalyst in the human body.

45. Enzymes • Enzymes: Function as biological catalysts to permit the biochemical reactions to occur rapidly at normal temperatures. • Substrate: A reactant molecule onto which the enzyme acts; each enzyme only binds to a specific substrate. • Active Site: Part of the enzyme that catalyzes the reaction, • Apoenzyme: Protein portion of an enzyme. • Cofactor: Nonprotein portion of an enzyme.

46. Metabolism • Metabolism: The sum of all chemical reactions in the body. Has 2 divisions: • Anabolism: Energy requiring reactions where small molecules are bonded to form larger ones. • AKA Synthesis or Endergonic Reactions • Catabolism: Energy releasing reactions where large molecules are broken down into smaller ones. • AKA Decomposition or Exergonic Reactions

47. Adenosine Triphosphate (ATP) • The body’s most important energy-transfer molecule! • Much of the energy used to synthesize ATP comes from glucose oxidation. • First stage of glucose oxidation is glycolysis (meaning “sugar splitting”)

48. Glycolysis • Glucose split into 2 Pyruvic acid molecules • 2 molecules of ATP produced, but most energy retained in the pyruvic acid • If oxygen is not available than anaerobic metabolism takes place (fermentation) • Produces lactic acid (toxic end product responsible for muscle soreness & converted back to pyruvic acid by the liver) • Enables glycolysis to continue without oxygen • If oxygen is available, than aerobicmetabolism takes place • Break pyruvic acid down into Carbon dioxide (CO2) and water (H2O) • Generates a total of 38 ATP • Glycolysis Anamation

49. Nucleic Acid • Nucleic Acid: polymers of nucleotides or chains of repeating monomers • HUGE organic molecules containing carbon, hydrogen, oxygen, nitrogen, and phosphorous. • Includes… • Deoxyribonucleic Acid (DNA) • Ribonucleic Acid (RNA)

50. DNA • Largest nucleic acid is Deoxyribonucleic acid (DNA) that constitutes the human genome (genes) • Provides genetic code (instructions) for the manufacture of all proteins • Transfers genetic information from cell to cell when cell division take place & from generation to generation in reproduction • Composed of a double-stranded helix containing 4 nitrogenous bases in set pairs: • Adenine (A) bonds to Guanine (G) in larger double-ring bases known as purines. • Thymine (T) bonds to Cytosine (C) in smaller single-ring bases known as pyramidines.