Chemistry for Anatomy and Physiology

Matter

• Can be seen, smelled or felt

• Occupies space and has mass (weight)

• We look at how building blocks are put together

Energy

• The ability to do work• Massless; measured by its effect on matter

Types of Energy

• Chemical

• Electrical

• Mechanical

• Radiant

Chemical Energy

Stored in atomic bonds

Released when bonds are broken

Electrical Energy

• Movement of charged particles

• Electrons along a wire at home

• Charged particles across a membrane in your body

Mechanical Energy

• Running, Riding a bike, paddling a canoe…

• Muscle contraction moves the bones of your body

Radiant Energy

• Travels in waves• Electromagnetic Spectrum• Includes x-rays, infrared, visible light, radio and

Ultraviolet• Important in vision and Vitamin D synthesis

Can we convert from one type to another???

• While it is never created or destroyed, some energy is lost as heat.

• Example= Eating, only 10% of the energy is retained and the rest is lost as heat.

Path of Energy

• Begins as sun energy

• Photosynthesis converts sun energy to chemical

• We eat plants and absorb the nutrients

• When we eat, chemical reactions produce heat

• Keeps our body temperature stable

• Provides building blocks for macromolecules

Food to Macromolecules

Energy Storage

• Energy is stored in ATP molecules for use in all activities

• The energy is stored in the last phosphate bond

• ATP breaks off a phosphate and becomes ADP

ATP and ADP

ATP = Fully Charged Battery ADP = Partially Charged Battery

What good is heat?

• Helps us maintain our body temperature

• Speeds up reactions in our body

• It is part of our ability to maintain homeostasis

Atomic Particles

Particle Location Charge Mass

Proton Nucleus +1 1 amu

Neutron Nucleus 0 1 amu

Electron Orbitals -1 0 amu

Common Elements (p30 in 9th)(p28 in 8th)

Elem % At #

•O 65.0% 8

•C 18.5% 6

•H 9.5% 1

•N 3.2% 7

•Ca 1.5% 20

•P 1.0% 15

• The number of protons identify the element and is the same as the atomic number

• The atomic mass is the number of protons plus the number of neutrons

Diagram C, H, N, O, P, S

Isotopes

• Iso=same

• Same element; different atomic mass

• Same number of protons

• Different number of neutrons

Radioisotopes

• Heavy isotopes tend to decompose to the lighter form

• The decay is called radioactivity

• Used to “Tag” biological molecules (PET scan)

• Treatment of certain localized cancers

Types of Bonds

Type Formed When… Characteristics

Ionic Electron is Transferred

Between atoms with different electronegativity

Covalent Electron is Shared Very strong bond

Van der Waals Forces or Hydrogen Bonds

Attraction between oppositely charged regions of molecules

Hydrogen bonds individual = weak

many = strong

Radioactivity• Alpha or Beta

particles or gamma rays are given off from the nucleus

• Alpha penetrates the least, gamma, most

• It is the electrons that are sent flying that does damage

Molecules and Compounds

• Molecules are two or more atoms of the same element that are joined

• H2 or O2

• Compounds are two or more atoms of different elements join together.

• CH4 or H2O

Ionic – Electron Transferred

Covalent – Electron Shared

Van der Waals Forces (oppositely charged regions )

Synthesis Reaction

• Two or more atoms or molecules combine to form a larger more complex molecule

• A + B → AB

Decomposition Reaction

• When a molecule is broken down into smaller less complex molecules

• AB → A + B

Exchange Reaction

• Involves both synthesis and decomposition. Bonds are both made and broken and a switch is made

• AB + CD → AD + BC

Organic vs Inorganic

Organic = Carbon Inorganic = No Carbon

Inorganic

Properties of Water

• #1 High Heat Capacity

• Water can absorb or release large amounts of heat before its temperature changes

• Prevents temperature changes in our body

Properties of Water

#2 Polarity• Water molecules

have a slightly negative charge near the oxygen atom and a slightly positive charge around the hydrogen atom.

Properties of Water

#2 Universal Solvent• Water dissolves more

substances than sulfuric acid because of its polar characteristic. It can surround molecules of a substance and pull it apart.

Water Properties

• #3 Chemical Reactivity• Can break down

molecules into smaller less complex forms

• Hydrolysis Reaction

Hydro =Water

Lys =Splitting

Water Properties

• #4 Cushioning• Protective

function in the form of fluid around sensitive organs

• Like: the brain, or a developing fetus

Other Properties of Water

Cohesion • Water is attracted to

other water. This is called cohesion.

Other Properties of Water

Adhesion• Water can also be

attracted to other materials. This is called adhesion.

Other Properties of Water

Density• Ice is less dense

than water which is

why it floats.

It expands as it freezes

Fish can live in water during winter

Other Properties of Water

• Surface Tension• Cohesion of water

molecules at the surface of a body of water causes the water to pull itself into a shape with the smallest amount of surface area (sphere).

• Surface tension allows water striders to 'skate' across the top of a pond. (Cohesion)

Other Properties of Water• Capillary Action• Adhesive properties of

water. Placing a straw into a glass of water, it 'climbs' up the straw. Molecules are attracted to the straw molecules (adhesion). When one water molecule moves, the other water molecules follow (cohesion)

• Capillary action is limited by gravity and the size of the straw. Plants take advantage of capillary action to pull water into the roots.

Salts

• Ionic Compound• Dissociate in water to:

Cation + and Anion –• Calcium and

Phosphorus (bones and teeth) and Sodium and Potassium

• ELECTROLYTES conduct current in solution

Acids and Bases

• Acids = Proton donor, in the form of H+ (hydrogen or naked proton)

• Strong acids liberate all of their protons

• Sour / burn

• Bases = Proton acceptor or dissociate to give off OH- ions (hydroxyl)

• Strong bases give off all OH-

• Bitter / slippery

Neutralization

• Neutral pH is 7• Combine acid and

base to neutralize• Buffers are weak acid

and bases that maintain pH stability by taking up excess H+ or OH- ions

• If blood is too acidic it will not carry oxygen

Categories of Organic Molecules

• Carbohydrates• Lipids• Proteins • Nucleic Acids

Categories of Organic Molecles

Molecule Building Blocks Examples Uses

Carbohydrates

C H O

Monosaccharides Sugars andStarches

Quick Energy

LipidsC H O

Glycerol and Fatty Acids

Fats, Oils, Waxes and Steroids

Stored EnergyCell Membranes

ProteinsC H N O

Amino Acids MuscleEnzymesCollagenAntibodies

Help Carry Out Cellular Activities

Nucleic AcidsC H N O P

Nucleotides DNA, RNA Instructions for all cell activities

Help make proteins

Carbohydrate

Lipids

Protein

Nucleic Acid

Building Blocks

4 Groups of Organic Compounds

Enzymes

Enzymes

• Enzymes = Catalysts that speed up reactions in our body

• Enzymes have a specific job – each fits like a lock and key with its specific substrate

How Enzymes Work

Four steps in the process of an enzyme working. 1. An enzyme and a substrate (the biological molecule that the enzyme will attack) are in the same area. 2. The enzyme grabs onto the substrate with a special area called the active site which is a specially shaped area of the enzyme that fits around the substrate. The active site is the keyhole of the lock. 3. A process called catalysis happens which is when the substrate is changed ( broken down or combined to make something new)4. When the enzyme lets go, it returns to normal, ready to do another reaction. The substrate is no longer the same and is now called the product.

Can you stop them????

• Good question!

• There are many factors that can regulate enzyme activity, including temperature, activators, pH levels, and inhibitors.

Any factors that affect the shape of an enzyme affect the enzyme’s activity. What effect

does pH and temperature have on an enzymes ability to catalyze (speed up) a reaction?

• Enzymes work well within very specific ranges of pH and temperature. If the pH or temperature changes to outside of the range, the enzyme shape changes and thus no longer works to speed up the reaction.