Topic 2- The Chemical Level of Organization

Chemistry

The science of structure ad interactions of matter

Matter

Anything tat has mass and takes up space

Mass

The amount of matter a substance contains

Weight

The force of gravity acting on a mass

Liquid

Some space between molecules

Gas

A ton of space between molecules

Solid

No space between molecules

The Human body is composed of ____ different elements

26

4 major elements make up ____% of our body's mass

96%

Oxygen

Carbon

Hydrogen

Nitrogen

8 Lesser elements compose ____%

3.6%

Found in bones

14 trace elements make up the remaining ____%

0.4%

Vital to the human body

Protons

Positive

Large

Neutrons

Neutral

Large

Add mass

Electrons

Negative

Small

Light

Atomic number

The number of protons in an atom

Mass number

The sum of protons and neutrons in an atom and indicates how much the atoms "weighs"—this is always a whole number.

Isotope

Extra protons in the nucleus

Daltons

Measure the mass of an atom

Atomic mass

The average mass of all naturally occurring isotopes—since this is an average, it is not exactly a whole number.

Ions

Atoms that have given up or gained an electron in their outer electron shell

Molecules

Formed when atoms share electrons

Compound

A substance that can be broken down into 2 or more different elements

Free radical

An electrically charged atom or group of atoms with an unpaired electrons in its outermost shell

-unstable and highly reactive

Antioxidants

Substances that inactive oxygen- derived free radicals

Ionic bonds

Form when an atom loses or gains a valence electron

Cations

Positively charged ions that have given up one or more electrons

-Electron donors

Anions

Negatively charged ions that have picked up one or more electrons that another atom has lost

-Electron acceptors

Covalent bonds

Formed by the atoms of molecules sharing one, two, or three pairs of their valence electrons

-Strongest chemical bonds

Nonpolar covalent bond

Atoms share the electrons equally

- most common type of covalent bonds

Polar covalent bonds

Formed by the unequal sharing of electrons between atoms

-extremely important because all-important water molecules make use of this bond

Hydrogen bonds

weak interactions between hydrogen and adjacent electronegative atoms like oxygen or sulfur

Metabolism

Sum of all the chemical reactions in the body

Law of conservation of energy

The total mass of reactants equals the total mass of products

Kinetic energy

energy of matter in motion

Potential energy

Energy stored by matter- due to an objects position in space or stored in chemical bonds

Exergonic

Reaction releases energy by breaking a bond with more energy than the one being formed

Endoergonic

Reaction requires that energy be added usually from a molecule called ATP to form a bond

Activation Energy

The energy required to break chemical bonds in the reactant molecules so a reaction can start

Catalysts

Chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur

Synthesis reactions

Anabolism

Building something bigger

A+B> AB

Decomposition (Degradation) reactions

Catabolism

Break something down

AB> A+B

Exchange reactions

AB+CD> AD+CB

Reversible reactions

You can have product and a start and you can go back in between the two states

AC<>A+C

Inorganic compounds (water, salts, acids, bases)

Structurally simple molecules that usually lack carbon

Organic compounds

always contain carbon and are usually large, complex

molecules.

-Always have covalent bonds

Water

Most important and abundant inorganic compound in all living systems

Polarity

The uneven sharing of valence electrons that enables reactants to collide to form products

Solvent

Dissolves the solute

Hydrophilic

Polar covalent bonds

-like water

Hydrophobic

Non-polar covalent bonds

-do not like water

Heat capacity

It can absorb or release a relatively large amount of heat with only a modest change in its own temperature

Heat of vaporization

amount of heat needed to change from a liquid to a gas

Mixture

A combination of elements or compounds that are physically blended together but are not bound by chemical bonds

Solution

a substance called the solvent dissolves another substance called the solute. Usually there is more solvent the solute in a solution

Colloid

Differ from a solution mainly on the basis of the size of its particles, with the particles in the colloid being large enough to scatter light

Suspension

The suspended material may mix with the liquid or suspending medium for some time, but it will eventually settle out

Concentration

A molecule is a way of stating the amount of that molecule in solution

Percent

Gives the relative mass of a solute found in 100ml of a solution

Mole

A convenient way of counting large numbers of small things

Buffer systems

Usually consists of a weak acid and a weak base

pH of blood

7.4

Functional groups

Esters, amino, carboxyl, phosphate groups

Polymers

Very large moelcules

Isomers

The same molecular formulas but different structures

Carbohydrates

Provide most of the chemical energy needed for life

Monosaccharides

Simplest sugars

-5 carbon sugars are used in nucleic acids

-6 carbon sugars are the most easily recognizable in our diet

Disaccharides

Made by combining 2 monosaccharides by removing a water molecule

Polysaccharides

largest carbohydrates

-contains hundreds monosaccharides

Glycogen

Most common polysaccharide found in the human body

Lipids

Organic molecules

-Contains carbon, hydrogen, and oxygen

Lipids are hydrophobic. Why?

Do not have many polar covalent bonds, have less oxygen gives less interaction between the lipid and water

Fatty acids

simplest form of lipids. Building blocks of triglycerides and phospholipids

-Consists of a carboxyl groups and a hydrocarbon chain

Saturated fatty acids

Contain single covalent bonds between carbon atoms and as a result each carbon is saturated with H atoms

Unsaturated fatty acids

contain 1 or more double covalent bonds between C atoms. Thus the C are not completely saturated with H atoms

Triglycerides

Most plentiful lipids in the body and provide protection, insulation, and energy

-Provide more than twice as much energy per gram as either carbohydrates or proteins

Triglycerides at room temperature

Solid-Fats, saturated fatty acids

Liquid-Oils, unsaturated fatty acids

Phospholipids

important membrane components

-Polar head and 2 non-polar tails

Steroids

Lipids molecules that have four rings of carbon atoms

-Sex hormones

-Bile salts

-Some vitamins

-Cholesterol

Proteins

Large molecules that contain carbon, hydrogen, oxygen, and nitrogen.

Amino acids

Monomers of proteins

Dipeptides

Formed from 2 amino acids joined by a covalent bond

Polypeptide

Chains contains 10 to 2000 amino acids

Primary level at which proteins are structurally organized

Gives the unique sequence of AA; genetically determined (looks like a string of beads)

Secondary level at which proteins are structurally organized

The repeated twisting and folding of primary sequence (alpha helix and beta pleated sheets between non sequential R groups)

Tertiary level at which proteins are structurally organized

The 3 dimensional shape (folding of secondary level of organization)

Quaternary level at which proteins are structurally organized

Arrangement of individual polypeptide chains in proteins containing more than 1 polypeptide

Denaturation

loss of protein structure

Ensymes

Special proteins that catalyze metabolic reactions in all living cells

Substrate

The substance upon which an anzyme has its effect

-Two parts

---Apoenzymes (protein part)

---Cofactor (Non-protein part)

Three important properties of enzymes

1. Enzymes are highly specific

2. Enzymes are highly efficient

3. Enzymes are subject to a variety of cellular controls

Nucleic acids

Huge organic molecules composed of monomeric nucleotide

-Contain carbon, hydrogen, oxygen, nitrogen, phosphorus, DNA and RNA

DNA

Molecules remain inside the nucleus of cells and are the "master" template of our genetic code.

RNA

Slightly different nucleic acid macromolecule that relays instructions from the nucleus to guide assembly of amino acids into proteins in the cytoplasm.

ATP

used as a temporary storage of energy that is being transferred from exergonic catabolic reactions to cellular activities.