Anatomy & Physiology I PDF

Anatomy & Physiology I The Principles of Chemistry Objective 2 Chapter 2 (pp. 38-59) © 2016 Pearson Education, Inc. Objectives 2. Discuss the basic principles of chemistry as they apply to body processes. 2.1 Define key terms related to basic chemistry. 2.2 Discuss organic and inorganic chemist...

Anatomy & Physiology I The Principles of Chemistry Objective 2 Chapter 2 (pp. 38-59) © 2016 Pearson Education, Inc. Objectives 2. Discuss the basic principles of chemistry as they apply to body processes. 2.1 Define key terms related to basic chemistry. 2.2 Discuss organic and inorganic chemistry. © 2016 Pearson Education, Inc. Why This Matters: • Understanding chemistry and biochemistry helps to determine the most effective solutions to use to treat dehydration and fluid loss • Important in the nursing process • Helps link knowledge to care © 2016 Pearson Education, Inc. Chemistry and Physiological Reactions • Body is made up of many chemicals • Chemistry underlies all physiological reactions: – Movement, digestion, pumping of heart, nervous system • Chemistry can be broken down into: – Basic chemistry – Biochemistry © 2016 Pearson Education, Inc. Basic Chemistry Matter and Energy Matter • Matter is anything that has mass and occupies space – Matter can be seen, smelled, and/or felt © 2016 Pearson Education, Inc. Matter • States of matter – Matter can exist in three possible states: • Solid: definite shape and volume • Liquid: changeable shape; definite volume • Gas: changeable shape and volume – Examples of each are found in the human body? © 2016 Pearson Education, Inc. Atoms and Elements • All matter is composed of elements • Elements are substances that cannot be broken down into simpler substances by ordinary chemical methods • Four elements make up 96% of body: Carbon, oxygen, hydrogen, and nitrogen © 2016 Pearson Education, Inc. Molecules and Compounds • Atoms are the building blocks of elements • Atoms combine to form molecules and compounds • When 2 or more like atoms combine they form molecules; eg: O2 • When 2 or more different kinds of atoms bind they form molecules of a compound; eg: H2O Covalent compound © 2016 Pearson Education, Inc. Mixtures • Most matter exists as mixtures: two or more components that are physically intermixed • Three basic types of mixtures – Solutions – Colloids – Suspensions © 2016 Pearson Education, Inc. Figure 2.4 The three basic types of mixtures. Solution Colloid Suspension Solute particles are very tiny, do not settle out or scatter light. Solute particles are larger than in a solution and scatter light; do not settle out. Solute particles are very large, settle out, and may scatter light. Solute particles Solute particles Solute particles Example Example Example Mineral water Jell-O Blood Plasma Unsettled Settled © 2016 Pearson Education, Inc. Settled red blood cells Mixtures (cont.) • Solutions – Are homogeneous mixtures, meaning particles are evenly distributed throughout – Solvent: substance present in greatest amount • Usually a liquid, such as water – Solute(s): substance dissolved in solvent • Present in smaller amounts • Example: blood sugar – glucose is solute, and blood (plasma) is solvent © 2016 Pearson Education, Inc. Mixtures (cont.) • Colloids – Also called emulsions – Composition is dissimilar in different areas of the mixture = heterogeneous – Can take on a sol-gel transformation meaning it can change from a fluid to a more solid state • Ex: jello © 2016 Pearson Education, Inc. Mixtures (cont.) • Suspensions – Heterogeneous mixtures that contain large, visible solutes that do settle out – Blood is considered a suspension because if left in a tube, the blood cells will settle out © 2016 Pearson Education, Inc. Part 2 – Biochemistry • Biochemistry is the study of chemical composition and reactions of living matter • All chemicals either organic or inorganic – Inorganic compounds • Water, salts, and many acids and bases • Do not contain carbon – Organic compounds • Carbohydrates, fats, proteins, and nucleic acids • Contain carbon, are usually large, and are covalently bonded • Both equally essential for life © 2016 Pearson Education, Inc. 2.6 Inorganic Compounds Water • Most abundant inorganic compound – Accounts for 60%–80% of the volume of living cells • Most important inorganic compound because of its properties – High heat capacity – High heat of vaporization – Polar solvent properties – Reactivity – Cushioning © 2016 Pearson Education, Inc. Water • High heat capacity – Ability to absorb and release heat with little temperature change – Prevents sudden changes in temperature • High heat of vaporization – Evaporation requires large amounts of heat – Useful cooling mechanism © 2016 Pearson Education, Inc. Water (cont.) • Polar solvent properties – Dissolves and dissociates ionic substances – Forms hydration (water) layers around large charged molecules • Example: proteins – Body’s major transport medium © 2016 Pearson Education, Inc. Water (cont.) • Reactivity – Necessary part of hydrolysis and dehydration synthesis reactions • Cushioning – Protects certain organs from physical trauma • Example: cerebrospinal fluid cushions nervous system organs © 2016 Pearson Education, Inc. Salts • Salts are ionic compounds that dissociate into separate ions in water – All ions are called electrolytes because they conduct electrical currents in solutions – Separate into cations (positively charged molecules) and anions (negatively charged) © 2016 Pearson Education, Inc. Salts (cont.) • Salts (cont.) – All ions are called electrolytes because they can conduct electrical currents in solution – Ions play specialized roles in body functions • Example: sodium, potassium, calcium, and iron – Ionic balance is vital for homeostasis – Common salts in body • NaCl, CaCO3, KCl, calcium phosphates © 2016 Pearson Education, Inc. Clinical – Homeostatic Imbalance 2.1 • Ionic balance is vital for homeostasis • Kidneys play a big role in maintaining proper balance of electrolytes • If electrolyte balance is disrupted, virtually all organ systems cease to function © 2016 Pearson Education, Inc. Acids and Bases • Acids and bases are considered electrolytes • pH scale • • • • • • Records a substance as acidic, basic or neutral Awards a score between 0-14 A substance scoring 7 is neutral A substance scoring below 7 are acidic A substance scoring above 7 are alkaline or basic See Figure 2.13; p. 40 (pH scale) © 2016 Pearson Education, Inc. 2.7 Organic Compounds: Synthesis and Hydrolysis • Organic molecules contain carbon – Exceptions: CO2 and CO, which are inorganic • Carbon is electroneutral – Shares electrons; never gains or loses them – Forms four covalent bonds with other elements – Carbon is unique to living systems • Major organic compounds: carbohydrates, lipids, proteins, and nucleic acids © 2016 Pearson Education, Inc. 2.8 Carbohydrates • Major source of cellular fuel; structural molecules • include sugars and starches • Contain C, H, and O – Hydrogen and oxygen are in 2:1 ratio • Three classes: – Monosaccharides: one single sugar Monomers: smallest unit of carbohydrate – Disaccharides: two sugars – Polysaccharides: many sugars © 2016 Pearson Education, Inc. 2.8 Carbohydrates • Monosaccharides – Simple sugars – The most basic units of carbohydrates – Important monosaccharides Ex: Glucose (blood sugar) and Fructose © 2016 Pearson Education, Inc. Carbohydrates (cont.) • Disaccharides – Double sugar formed from two monosaccharides (ex: sucrose = glucose + fructose) – Too large to pass through cell membranes – Important disaccharides • Sucrose, maltose, lactose © 2016 Pearson Education, Inc. Carbohydrates (cont.) • Polysaccharides – Made up by many sugars (ex: starch, glycogen, cellulose) – Important polysaccharides • Starch: carbohydrate storage form used by plants • Glycogen: carbohydrate storage form used by animals – Glycogen is stored in skeletal muscles and liver cells © 2016 Pearson Education, Inc. 2.9 Lipids • Contain C, H, O, but less than in carbohydrates, and sometimes contain phosphorus (P) • Insoluble in water • Main types: – Triglycerides or neutral fats – Phospholipids – Steroids © 2016 Pearson Education, Inc. Lipids (cont.) • Triglycerides or neutral fats – Called fats when solid and oils when liquid – found in your blood. – body converts any calories it doesn't need to use right away into triglycerides. – stored in your fat cells. – hormones release triglycerides for energy between meals – Main functions: • Energy storage • Insulation • Protection © 2016 Pearson Education, Inc. Lipids (cont.) • Triglycerides can be constructed of: – Saturated fatty acids • Solid at room temperature (Example: animal fats, butter) • Ex: coconut oil © 2016 Pearson Education, Inc. Lipids (cont.) – Unsaturated fatty acids • Liquid at room temperature (Example: plant oils, such as olive oil) • Heart healthy • Can be found in avocado, nuts, oils • Trans fats – modified oils; unhealthy (cakes, doughnuts, fast food, pizza) *overuse of trans fats can increase the risk of heart disease • Omega-3 fatty acids – “heart healthy” (fish, flaxseed, fish oil) *decrease risk of heart disease and inflammatory disease © 2016 Pearson Education, Inc. Lipids (cont.) • Phospholipids – Modified triglycerides – “Head” and “tail” regions have different properties • Head is attracted to water (hydrophilic) • Tails are repelled by water (hydrophobic) – Important in cell membrane structure © 2016 Pearson Education, Inc. Lipids (cont.) • Steroids – Common steroids: cholesterol, vitamin D, steroid hormones, and bile salts – Most important steroid is cholesterol • Is building block for vitamin D, steroid synthesis, and bile salt synthesis • Important in cell plasma membrane structure • Can be found in eggs, meat & cheese © 2016 Pearson Education, Inc. 2.10 Proteins • Comprise 20–30% of cell mass • Considered to be the body’s basic structural material • Plays the most varied functions of any molecules in the body • It is the main building block of the body • 4 levels of structure: – – – – Primary Secondary Tertiary Quaternary © 2016 Pearson Education, Inc. 2.11 Nucleic Acids • Nucleic acids, composed of C, H, O, N, and P, are the largest molecules in the body • Two major classes: – Deoxyribonucleic acid (DNA) – Ribonucleic acid (RNA) © 2016 Pearson Education, Inc. 2.11 Nucleic Acids • DNA holds the genetic blueprint for the synthesis of all proteins – Double-stranded helical molecule (double helix) located in cell nucleus – Replicates itself and provides basic instructions for building every protein in the body © 2016 Pearson Education, Inc. 2.11 Nucleic Acids • RNA links DNA to protein synthesis and is slightly different from DNA © 2016 Pearson Education, Inc. Animation – DNA and RNA © 2016 Pearson Education, Inc. 2.12 ATP and Metabolism • ATP (adenosine triphosphate) = Chemical energy released when glucose is broken down • ATP directly powers chemical reactions in cells – Offers immediate, usable energy needed by body cells © 2016 Pearson Education, Inc.