ESSENTIALS OF BODY CHEMISTRY

MATTER, ELEMENTS, AND ATOMSMATTERMATTER-anything that -anything that

occupies space and has massoccupies space and has massMASSMASS-the amount of matter -the amount of matter

in an objectin an object

MATTER, ELEMENTS, AND ATOMSELEMENTSELEMENTS-chemical -chemical

substances that cannot be substances that cannot be broken downbroken down

ATOMSATOMS- smallest unit of an - smallest unit of an element that retains the element that retains the chemical characteristicchemical characteristic

ELEMENTS

Represented by either one-Represented by either one-or-two-letter symbol. Ex. or-two-letter symbol. Ex. H,O,NaH,O,Na

106 elements106 elements

ELEMENTS

92 occur naturally92 occur naturally24 found in living organisms24 found in living organisms

ATOMS

STRUCTURE OF AN ATOM

NUCLEUSNUCLEUS-- PROTONS-PROTONS- positively charged particles positively charged particles NEUTRONSNEUTRONS- uncharged particles- uncharged particles ELECTRONSELECTRONS- negatively charged particles- negatively charged particles

ATOMIC NUMBER AND WEIGHTATOMIC NUMBERATOMIC NUMBER- # of - # of

protons in the nucleus (same as protons in the nucleus (same as # of electrons)# of electrons)

ATOMIC WEIGHT- ATOMIC WEIGHT- the the number of protons plus the number of protons plus the number of neutronsnumber of neutrons

ELECTRON SHELLS

ELECTRON SHELLS(energy ELECTRON SHELLS(energy levels)- levels)- concentric circles lying concentric circles lying around the nucleusaround the nucleus

First energy levelFirst energy level- can hold no - can hold no more than two electronsmore than two electrons

ELECTRON SHELLS

SecondSecond-maximum of eight-maximum of eightThird-Third- when atomic number is when atomic number is

less than 20 it can hold eight less than 20 it can hold eight electronselectrons

ThirdThird- if is more complex, it - if is more complex, it can hold up to 18can hold up to 18

HOW ATOMS COMBINE MOLECULES-MOLECULES- when two or more when two or more

atoms combine. EX. Oatoms combine. EX. O2 2

COMPOUNDSCOMPOUNDS- a molecule that - a molecule that contains at least two different kinds contains at least two different kinds of atoms. Ex. COof atoms. Ex. CO22 NaCl NaCl

CHEMICAL BONDSCHEMICAL BONDS- atoms that - atoms that are held together by forces of are held together by forces of attractionattraction

IONIC BONDS ION-ION- when an atom gains or loses when an atom gains or loses

electrons and acquires an electrical electrons and acquires an electrical chargecharge

CATIONCATION- when an atom loses one - when an atom loses one or more electrons and becomes or more electrons and becomes positivepositive

ANIONANION- when an atom gains one - when an atom gains one or more electrons and becomes or more electrons and becomes negativenegative

IONIC BOND

IONIC BONDIONIC BOND- when an ion or - when an ion or group of ions becomes attracted group of ions becomes attracted to an appositively charged ion to an appositively charged ion or group of ionsor group of ions

IONIC BONDING

COVALENT BONDS

Covalent bondCovalent bond- when atoms - when atoms share electrons with other atomsshare electrons with other atoms

COVALENT BOND

WATER AS A SOLVENT

SOLUTIONSOLUTION- combination of - combination of solvent plus solutesolvent plus solute

SUSPENSIONSUSPENSION-suspended -suspended material mixes with the liquid or material mixes with the liquid or suspending medium, but will suspending medium, but will eventually settle out of the eventually settle out of the mixturemixture

ACIDS, BASES, AND SALTS

IONIZATION (dissociation)IONIZATION (dissociation)- - when molecules of inorganic when molecules of inorganic acids, bases, or salts are acids, bases, or salts are dissolved in water in the body dissolved in water in the body cells. ex. electrolytescells. ex. electrolytes

ACID

ACIDACID- substance that - substance that dissociates into one or more dissociates into one or more hydrogen ions and one or hydrogen ions and one or more negative ions. more negative ions. HCl --HCl -- H H++ + Cl + Cl--

BASES

BASEBASE- dissociates into one or - dissociates into one or more hydroxyl ions and one or more hydroxyl ions and one or more positive ions. more positive ions. NaOH--NaOH-- Na Na++ + OH + OH--

SALTS

SALT-an acid reacts with a SALT-an acid reacts with a base. base. HCl+ NaOH --HCl+ NaOH --NaCl+ HNaCl+ H22OO

Ph SCALE

It runs from 0-14, with neutrality It runs from 0-14, with neutrality at 7, and indicates the at 7, and indicates the concentration of free hydrogen concentration of free hydrogen ions in water.ions in water.

Each whole number on the ph Each whole number on the ph scale represents a 10-fold change scale represents a 10-fold change in acidityin acidity

Ph of common substances

Stomach juices- 1.4Stomach juices- 1.4 Lemon 2.2Lemon 2.2 Soft drinks- 3.0Soft drinks- 3.0 Coffee 5.0Coffee 5.0 Urine 5.0--8.0Urine 5.0--8.0 Distilled water 7.0Distilled water 7.0 Blood 7.4Blood 7.4

CONTROLLING PH WITH BUFFERSHomeostasis can be maintained Homeostasis can be maintained

only if there is a relatively only if there is a relatively constant pH of blood and other constant pH of blood and other body fluidsbody fluids

BUFFERSBUFFERS-chemicals that change -chemicals that change strong acids or bases into weak strong acids or bases into weak onesones

ORGANIC COMPOUNDS

Molecules that contain Molecules that contain carbon, hydrogen and oxygencarbon, hydrogen and oxygen

Ex. Carbohydrates, Lipids, Ex. Carbohydrates, Lipids, and Proteinsand Proteins

CARBOHYDRATES

Molecules that includes Molecules that includes sugars and starchessugars and starches

Form structural unitsForm structural units

CARBOHYDRATES

Convert to proteins and fatsConvert to proteins and fatsFood reserve (glycogen)Food reserve (glycogen)Main function- provide Main function- provide

energy to sustain lifeenergy to sustain life

MONOSACCHARIDES

Simple sugars containing 3-7 Simple sugars containing 3-7 carbon atomscarbon atoms

DISACCHARIDES

Two monosaccharides Two monosaccharides

DISACCHARIDES

Dehydration synthesisDehydration synthesis- when two - when two monosaccharides combine to monosaccharides combine to form a dissaccharide molecule form a dissaccharide molecule and a molecule of water is lost. and a molecule of water is lost. C C66HH1212OO66 +C+C66HH1212OO66CC1212HH2222OO1111 + H + H22OO

HYDROLYSIS

Hydrolysis(digestion)Hydrolysis(digestion) breaking of disaccharides by breaking of disaccharides by adding wateradding water

POLYSACCHARIDES

Three or more Three or more monosaccharides joined monosaccharides joined together through dehydration together through dehydration synthesissynthesis

Can be broken down into Can be broken down into simple sugars by hydrolysissimple sugars by hydrolysis

POLYSACCHARIDES

Plants store energy in starchPlants store energy in starchAnimals store energy in Animals store energy in

glycogenglycogen

LIPIDS

Most are insoluble in waterMost are insoluble in waterFat molecule (triglyceride) Fat molecule (triglyceride)

includes one glycerol and three includes one glycerol and three fatty acidsfatty acids

TRYGLYCERIDES

LIPIDS

Saturated fatSaturated fat- saturated with - saturated with hydrogen- occur in animal hydrogen- occur in animal foods high in cholesterolfoods high in cholesterol

Unsaturated fatUnsaturated fat- olive oil and - olive oil and peanut oilpeanut oil

PROTEINS

They are the structure of body They are the structure of body cellscells

Amino Acids are the Amino Acids are the building blocks of proteinsbuilding blocks of proteins

FUNCTION OF PROTEINS

MOVEMENTMOVEMENT- ACTIN/MYOSIN- ACTIN/MYOSIN STRUCTURESTRUCTURE- COLLAGEN- COLLAGEN REGULATIONREGULATION- ENZYMES- ENZYMES TRANSPORTTRANSPORT- HEMOGLOBIN- HEMOGLOBIN DEFENSEDEFENSE- ANTIBODIES- ANTIBODIES

ENZYMES

Proteins produced by living Proteins produced by living cells to catalyze reactions in cells to catalyze reactions in bodybody

CatalystCatalyst- chemical substance - chemical substance that alters the speed of a that alters the speed of a chemical reactionchemical reaction

ENZYMES

CoenzymesCoenzymes non protein non protein molecules that help enzymes molecules that help enzymes functionfunction. Ex. Vitamins