Chemistry of Living Things

Rachel Hillard RN

Objectives: Anatomy and Physiology

Relate the importance of chemistry and biochemistry to health care

Explain the importance of water to our body

Describe the four main groups of organic compounds:Carbohydrates, fats, proteins, and nucleic acids

Item 1

Define matter and energyItem 2

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Item 3

Item 4

Explain the structure of an atom, element, and a compound

Objectives: Anatomy and Physiology

Explain the difference between the DNA molecule and the RNA molecule

Define the key words that relate to this chapter

Item 6

Explain the difference between an acid, base, and salt

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Item 9

Describe why homeostasis is necessary for good health

• Is the study of the structure of matter and the composition of substances, their properties, and their chemical reactions.

• Many chemical reactions in the human body• Digestion• Urine• Manufacture of proteins

Biochemistry: The study of the

Chemical reactions of living

Things.

• Chemistry

Chemical reactions necessary to sustain life

occur in the cells

• Anything that has weight (mass) and occupies space

• Has three forms:• Solid• Liquid• Gas

•Matter

• Matter is neither created nor destroyed

• Changes form through physical or chemical means

• Physical change: chewing a piece of food

• Chemical change: when chemicals change its composition

• Energy: the ability to do work or to put matter into motion.

• Potential • Kinetic

• Protons• (+) positive electric charge

• Neutrons

• Electrons• (-) negative electric charge

• Protons and neutrons make up the nucleus of the atom• Electrons make up the electron shell• # of protons and electrons are =

• Smallest piece of an element•Atoms

• Atoms can combine or share electrons for a chemical bond

• Positive charge: when one atom gives up an electron

• Isotopes: have the same # of protons but a different number of neutrons

• Radioactive isotopes: unstable atoms start to decay

•Atoms

• Can be used to study structure and function of particular tissues

• Most common treatment with• Thyroid• Prostate CA• CA of the bone pain

• Nuclear medicine•Radioactive Isotopes

• CAT or CT scan: (computed Axial Tomography)• MRI: (magnetic resonance Imaging)• PET: (Positron Emission Tomography)• Sonography or ultrasound • Bone, Liver, Brain, and Spleen Scan

• Non-invasive techniques •Medical Imaging

• A form of substance that can be neither created nor destroyed by ordinary means.

• Can exist in more than one phase in our bodies• Bone- calcium• Air- oxygen• Water- hydrogen and oxygen

• 92 elements found naturally in the world• Additional elements have been man-made• Each has a chemical symbol or abbreviation

• Group of like atoms•Elements

• Has different characteristics or properties depending on its elements

• Represented by formulas• H2O • NaCl• HCl• NaHCo3• NaOH• C6H12O6

• Various elements combine in a definite proportion by wt.•Compounds

• Unicellular• Multicellular• Take 20 essential elements • Organic compounds: have carbon, hydrogen, and oxygen

• All living things have the element carbon

•Living Organism

• H2O- Water can be broken down into smaller and smaller droplets.

• H20 is the smallest unit and still be a molecule

• Smallest unit of a compound that still has the properties of the compound and the capability to lead it’s own stable existence

•Molecules

• Ion- a positive or negatively charged particle • When atom gives up a electron (+)• When atom picks up a electron (-)

• Electrolytes- when compounds are in solution and act as if they have broken into individual pieces (ions)

• Na+ • Cl-

• Ions and Electrolytes

• Inorganic- does not contain carbon (C)• Exceptions CO2, CaCO3• Water is the most important inorganic compound to living

organisms

• Organic- found in living things and the products they make

• Are combined with hydrogen and other elements• > 100,000 known organic compounds

• 4 main types- carbohydrates, lipids, proteins, and nucleic acid

•Compounds

• Have twice as many hydrogen as oxygen and carbon atoms

• Three Groups:• Monosaccharides• Disaccharides• Polysaccharides

• C, H, O•Carbohydrates

• Can not be broken down any further• Types of Monosaccharides

• Glucose- main source of energy for cells• Stored in the liver and muscle cells as Glycogen

• Fructose- sweetest (fruit and honey)• Galactose- Helps to make breast milk • Ribose- RNA• Deoxyribose- DNA

• Greek words “mono” “sakcharon”•Monosaccharide’s

• Formed by dehydration synthesis• Examples:

• Sucrose (table sugar)• Maltose (malt sugar)• Lactose (milk Sugar)

Broken down by digestion (hydrolysis)

• Double sugar•Disaccharides

• Starch• Cellulose • Glycogen

• Broken down to disaccharides then to monosaccharide’s • Found in grain root vegetables “potatoes”

• Cellulose is the main structural component of plant tissue

• One chainlike molecule•Polysaccharides

• Examples:• Fats• Phospholipids• Steroids

• C, H, O •Lipids

• Amino acids• 22 different amino acids • Uses:

• Found in every part of a living cell• Outer protein coat of viruses• Binding and structural components

• (fingernails, hair, cartilage, ligaments, tendons, muscle)

• C, H, O, N, P, SULFUR•Proteins

• Control various chemical reactions in a cell• Provide energy for the cell• Assist in making of new cell parts• Control almost every process in a cell• Organic catalysts

• Affects the rate or speed of a chemical reaction without being changed

• Enzymes can be used over and over• Made up of all protein or part protein

• (apoenzyme)

• (coenzyme)

•Enzymes

• Deoxyribonucleic acid (DNA)• Ribonucleic acid (RNA)• Largest organic molecules

• Nucleotides

• C, O, H, N, P•Nucleic Acids

• Double-stranded molecule• Double helix

• Deoxyribose and phosphate • Heredity• 46 (23 pairs) of chromosomes• Passes genetic information from one generation to the next

•DNA

• Ribose and phosphate group• Single stranded• Three types

• m-RNA (messenger)• t-RNA (transfer)• r-RNA (ribosomal)

• r-RNA helps in the attachment of m-RNA to the ribosome

•RNA

• Is a substance that when dissolved in water will ionize into + charged hydrogen ions (H+) and – charged ions of some other element.

• Taste sour• Blue Litmus pater is used to test acidity

•Acids

• Substance that when dissolved in water ionized into – charged hydroxide (OH-) ions and positively charged ions of a metal

• Taste bitter and feel slippery between the fingers • Red Litmus paper to test for base

•Bases or alkali

• Is when an acid and a base are combined• Neutralization or exchange reaction

•salt

• Measure of the acidity or alkalinity of a solution• 0-14• 7= has same # of hydrogen and hydroxide ions• 0-6.9= acidic solution• 7.1- 14.0= basic or alkaline

•pH Scale

• Optimum cell function • Buffer- compound sodium bicarbonate help to maintain constant pH value

• Extracellular fluid- bathes the cell and transports nutrients

• Interstitial fluid- (blood, lymph, and fluid between tissue)

• Intracellular fluid- fluid within the cell•

• Living cells are nearly neutral•Homeostasis