module 2—chemical levels of organization

Human chemistry includes

organic molecules (carbon based)

biochemicals (produced by the body)

elements (inorganic and organic)

All matter in the world is composed of one or more…

elements

Element definition

a pure substance that is distinguished from all other matter by the fact that it cannot be broken down by ordinary means

The body cannnot make what

elements

Elements that are used in the body are derived from…

food and the air

What element is essential to the human body

calcium

What are the most abundant elements in the body

oxygen, carbon, hydrogen, nitrogen

T or F: elements rarely occur alone in nature

true

Compound definition

a substance composed of two or more elements joined by chemical bonds

Glucose always has these components

6 carbon, 6 oxygen, 12 hydrogen

Free radical definition

an atom or molecule with an unpaired electron in the outermost shell

Characteristics of free radicals

unstable

highly reactive

destructive to nearby molecules

How to stabilize a free radical

give up the unpaired electron

obtain an electron

Why does stabilizing a free radical disrupt homeostasis?

it breaks the molecule

Atom definition

the smallest quantity of an element that retains the unique properties of that element

Subatomic particles

proton, neutron, electron

Atomic number definition

the number of protons in the nucleus of the atom

The atomic number identifies…

the element

the usual number of electrons

Mass number defintion

the sum of the number of protons and neutrons in its nucleus

Ion definition

an atom that has an electric charge

Positively charged ion

cation

Negatively charged ion

anion

most individual atoms exist as…

ions

Ionic bond definition

close association between ions of opposite charge

Ionic bonds contain

1 metal element and 1 non metal element

Ions…

disassociate in water

Disassociation of ions in water produce…

electrical charges within the body

Behavior of ions can produce…

waves on EKGs or EEGs

Covalent bond definition

share electrons in a mutually stabilizing relationship

Covalent bonds involve…

2 non metal elements

Two kinds of covalent bonds

polar and non polar

Non polar covalent bond definition

covalently bonded molecules that are electrically balanced

sharing of negative electrons is relatively equal in the electrical pull of the positive protons in the nuclei

In a single covalent bond, how many pairs of electrons are shared

one pair

Examples of non polar molecules

fats and oils

What type of phobic are nonpolar covalent bonds

hydrophobic

Polar molecule definition

a molecule that contains regions that have opposite electrical charges

Polar molecules occur when atoms share electrons _____ in polar covalent bonds

unequally

Example of polar molecule

water

Characteristics of polar covalent molecules

dipoles

hydrophilic

Hydrogen bonds are a type of…

intermolecular bond

Hydrogen bonds are formed when a…

weakly positive hydrogen atom is attracted to a highly electronegative atom

What electronegative atoms are seen in hydrogen bonds

nitrogen, oxygen, fluorine, halogens

Van der waals forces are a type of…

intermolecular bond

Van der waals forces are…

weak and temporary attractions between nearby molecules

Van der waals forces are due to…

transient unequal charge distributions

Ionic compounds are dissolvable in…

polar solutions

Polar molecules are dissolvable in…

polar solutions

Non polar molecules are dissolvable in…

non polar solutions

What do polar and non polar interactions mean for human physiology?

creates essential compartments and biological structures

Ionic or covalent? H2O

covalent

Ionic or covalent? NaCl

ionic

Ionic or covalent? CO2

covalent

Ionic or covalent? NaSO4

ionic

Polar or nonpolar? H2O

polar

Polar or nonpolar? Cl2

nonpolar

Polar or nonpolar? CCl4

nonpolar

Polar or nonpolar? HCl

polar

Chemical energy is…

absorbed, stored, and released by chemical bonds

Mechanical energy…

directly powers the movement of matter

Example of mechanical energy

lifting a brick to place on a wall

the muscles provide the mechanical energy that moves the brick

Radiant energy is…

energy emitted and transmitted as waves rather than matter

The types of waves that can be emitted from decaying atomic nuclei

radio waves (long), microwaves, gamma rays (short)

The full spectrum of radiant energy is referred to as the…

electromagnetic spectrum

The body uses the ultraviolet energy of sunlight to convert a compound in the skin cells to…

vitamin D

The human eye has evolved to see wavelengths from red to violet in the spectrum called…

“visible light”

Electrical energy is supplied by…

electrolytes in the cells and body fluids

Electrolytes contributes to the…

voltage changes that help transmit impulses in nerve and muscle cells

A + B→AB

synthesis reaction

AB→A+B

decomposition reaction

A+BC→AB+CA+BC→AB+C,

AB+CD→AC+BDAB+CD→AC+BD, AB+CD→AD+BCAB+CD→AD+BC

exchange (subsitution) reaction

CxHx+O2 → CO2 + H2O

combustion reaction

Any chemical reaction can proceed in ____ ______ under the right conditions

either direction

What type of arrow shows reversibility of a chemical reaction

double equilibrium arrow

Law of mass action

direction of the reaction is influenced by the concentration of the reactants and products

The greater the surface area of the reactants…

the more readily they will interact

The larger the molecule…

the greater number of total bonds

Reactions involving smaller molecules with fewer total bonds are expected to…

proceed faster

Reactions that involve hydrogen are fairly…

reactive

Reactions involving helium are likely…

not to occur due to its stability

Nearly all chemical reactions occur at a faster rate at…

higher temperatures

Higher temperature means…

particles move faster and bump into each other more frequently

The more particles present in a given space…

the more likely they are to bump into each other

Chemist can speed up chemical reactions by…

increasing the concentration of particles

decreasing the volume of the space/increasing the pressure

Catalyst definition

a substance that increases the rate of a chemical reaction without undergoing any change

Enzyme definition

a catalyst composed of protein or ribonucleic acid (RNA)

How do enzymes work?

they lower the level of energy that needs to be invested in a chemical reaction

Is this reaction with or without an enzyme

without

Is this reaction with or without an enzyme?

with

Inorganic compound definition

a substance that does not contain both carbon and hydrogen

Examples of inorganic compounds

H2O, HCl, CO2

Organic compound definition

a substance that contains both carbon and hydrogen

Organic compounds are synthesized via…

covalent bonds within living organisms

What is the percentage of water that makes up an adult’s body weight

70

Where is the water contained in the human body

within cells

between cells that make up tissues and organs

Water in synovial fluid…

lubrictes the actions of body joints

Water in pleural fluid…

helps the lungs expand and recoil with breathing

Watery fluids help the GI tract by…

keeping flood flowing

ensures movement of adjacent abdominal organs are frictionless

Water also protects cells and organs from…

physical trauma

Water does what for the brain

cushions it within the skull

Water protects…

the delicate nerve tissue of the eyes