ESSENTIALS OF BODY CHEMISTRY

MATTER, ELEMENTS, AND ATOMS MATTER-anything that occupies space and has mass MATTER-anything that occupies space and has mass MASS-the amount of matter in an object MASS-the amount of matter in an object

MATTER, ELEMENTS, AND ATOMS ELEMENTS-chemical substances that cannot be broken down ELEMENTS-chemical substances that cannot be broken down ATOMS- smallest unit of an element that retains the chemical characteristic ATOMS- smallest unit of an element that retains the chemical characteristic

ELEMENTS Represented by either one- or-two-letter symbol. Ex. H,O,Na Represented by either one- or-two-letter symbol. Ex. H,O,Na 106 elements 106 elements

ELEMENTS 92 occur naturally 92 occur naturally 24 found in living organisms 24 found in living organisms

ATOMS

STRUCTURE OF AN ATOM NUCLEUS- NUCLEUS- PROTONS- positively charged particles PROTONS- positively charged particles NEUTRONS- uncharged particles NEUTRONS- uncharged particles ELECTRONS- negatively charged particles ELECTRONS- negatively charged particles

ATOMIC NUMBER AND WEIGHT ATOMIC NUMBER- # of protons in the nucleus (same as # of electrons) ATOMIC NUMBER- # of protons in the nucleus (same as # of electrons) ATOMIC WEIGHT- the number of protons plus the number of neutrons ATOMIC WEIGHT- the number of protons plus the number of neutrons

ELECTRON SHELLS ELECTRON SHELLS(energy levels)- concentric circles lying around the nucleus ELECTRON SHELLS(energy levels)- concentric circles lying around the nucleus First energy level- can hold no more than two electrons First energy level- can hold no more than two electrons

ELECTRON SHELLS Second-maximum of eight Second-maximum of eight Third- when atomic number is less than 20 it can hold eight electrons Third- when atomic number is less than 20 it can hold eight electrons Third- if is more complex, it can hold up to 18 Third- if is more complex, it can hold up to 18

HOW ATOMS COMBINE MOLECULES- when two or more atoms combine. EX. O 2 MOLECULES- when two or more atoms combine. EX. O 2 COMPOUNDS- a molecule that contains at least two different kinds of atoms. Ex. CO 2 NaCl COMPOUNDS- a molecule that contains at least two different kinds of atoms. Ex. CO 2 NaCl CHEMICAL BONDS- atoms that are held together by forces of attraction CHEMICAL BONDS- atoms that are held together by forces of attraction

IONIC BONDS ION- when an atom gains or loses electrons and acquires an electrical charge ION- when an atom gains or loses electrons and acquires an electrical charge CATION- when an atom loses one or more electrons and becomes positive CATION- when an atom loses one or more electrons and becomes positive ANION- when an atom gains one or more electrons and becomes negative ANION- when an atom gains one or more electrons and becomes negative

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

IONIC BONDING

COVALENT BONDS Covalent bond- when atoms share electrons with other atoms Covalent bond- when atoms share electrons with other atoms

COVALENT BOND

WATER AS A SOLVENT SOLUTION- combination of solvent plus solute SOLUTION- combination of solvent plus solute SUSPENSION-suspended material mixes with the liquid or suspending medium, but will eventually settle out of the mixture SUSPENSION-suspended material mixes with the liquid or suspending medium, but will eventually settle out of the mixture

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

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

BASES BASE- dissociates into one or more hydroxyl ions and one or more positive ions. NaOH--  Na + + OH - BASE- dissociates into one or more hydroxyl ions and one or more positive ions. NaOH--  Na + + OH -

SALTS SALT-an acid reacts with a base. HCl+ NaOH --  NaCl+ H 2 O SALT-an acid reacts with a base. HCl+ NaOH --  NaCl+ H 2 O

Ph SCALE It runs from 0-14, with neutrality at 7, and indicates the concentration of free hydrogen ions in water. It runs from 0-14, with neutrality at 7, and indicates the concentration of free hydrogen ions in water. Each whole number on the ph scale represents a 10-fold change in acidity Each whole number on the ph scale represents a 10-fold change in acidity

Ph of common substances Stomach juices- 1.4 Stomach juices- 1.4 Lemon 2.2 Lemon 2.2 Soft drinks- 3.0 Soft drinks- 3.0 Coffee 5.0 Coffee 5.0 Urine Urine Distilled water 7.0 Distilled water 7.0 Blood 7.4 Blood 7.4

CONTROLLING PH WITH BUFFERS Homeostasis can be maintained only if there is a relatively constant pH of blood and other body fluids Homeostasis can be maintained only if there is a relatively constant pH of blood and other body fluids BUFFERS-chemicals that change strong acids or bases into weak ones BUFFERS-chemicals that change strong acids or bases into weak ones

ORGANIC COMPOUNDS Molecules that contain carbon, hydrogen and oxygen Molecules that contain carbon, hydrogen and oxygen Ex. Carbohydrates, Lipids, and Proteins Ex. Carbohydrates, Lipids, and Proteins

CARBOHYDRATES Molecules that includes sugars and starches Molecules that includes sugars and starches Form structural units Form structural units

CARBOHYDRATES Convert to proteins and fats Convert to proteins and fats Food reserve (glycogen) Food reserve (glycogen) Main function- provide energy to sustain life Main function- provide energy to sustain life

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

DISACCHARIDES Two monosaccharides Two monosaccharides

DISACCHARIDES Dehydration synthesis- when two monosaccharides combine to form a dissaccharide molecule and a molecule of water is lost. C 6 H 12 O 6 +C 6 H 12 O 6  C 12 H 22 O 11 + H 2 O Dehydration synthesis- when two monosaccharides combine to form a dissaccharide molecule and a molecule of water is lost. C 6 H 12 O 6 +C 6 H 12 O 6  C 12 H 22 O 11 + H 2 O

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

POLYSACCHARIDES Three or more monosaccharides joined together through dehydration synthesis Three or more monosaccharides joined together through dehydration synthesis Can be broken down into simple sugars by hydrolysis Can be broken down into simple sugars by hydrolysis

POLYSACCHARIDES Plants store energy in starch Plants store energy in starch Animals store energy in glycogen Animals store energy in glycogen

LIPIDS Most are insoluble in water Most are insoluble in water Fat molecule (triglyceride) includes one glycerol and three fatty acids Fat molecule (triglyceride) includes one glycerol and three fatty acids

TRYGLYCERIDES

LIPIDS Saturated fat- saturated with hydrogen- occur in animal foods high in cholesterol Saturated fat- saturated with hydrogen- occur in animal foods high in cholesterol Unsaturated fat- olive oil and peanut oil Unsaturated fat- olive oil and peanut oil

PROTEINS They are the structure of body cells Amino Acids are the building blocks of proteins Amino Acids are the building blocks of proteins

FUNCTION OF PROTEINS MOVEMENT- ACTIN/MYOSIN MOVEMENT- ACTIN/MYOSIN STRUCTURE- COLLAGEN STRUCTURE- COLLAGEN REGULATION- ENZYMES REGULATION- ENZYMES TRANSPORT- HEMOGLOBIN TRANSPORT- HEMOGLOBIN DEFENSE- ANTIBODIES DEFENSE- ANTIBODIES

ENZYMES Proteins produced by living cells to catalyze reactions in body Proteins produced by living cells to catalyze reactions in body Catalyst- chemical substance that alters the speed of a chemical reaction Catalyst- chemical substance that alters the speed of a chemical reaction

ENZYMES Coenzymes non protein molecules that help enzymes function Coenzymes non protein molecules that help enzymes function. Ex. Vitamins