Transcript NUR101ModB

NUR 101: Body Structure and
Function
Module B – Chemistry of Life
Chemistry of Life
 BIOCHEMISTRY is devoted to studying
the chemical aspects of life. The basic
principles of anatomy and physiology are
ultimately based on principles of
chemistry.
Levels of Chemical
Organization
 MATTER is any thing that occupies
space and has mass.
 MOLECULES are particles of matter that
are composed of one or more smaller
units called atoms.
 ATOMS are composed of several kinds of
subatomic particles: protons, electrons,
and neutrons.
Atom Organization
 Atom nucleus is the center core of the
atom and contains protons and neutrons.
 Protons are positively charged particles
within the nucleus of an atom.
 Neutrons are electrically neutral particles
within the nucleus of an atom.
 Electrons are negatively charged
particles orbiting the nucleus of an atom.
Levels of Chemical Organization
 ELEMENTS are pure substances,
composed of only one kind of atom
 MOLECULES are particles of matter that
are composed of one or more smaller
units called atoms
 COMPOUNDS are composed of
molecules having more than one kind of
atom.
CHEMICAL BONDING
 IONIC BONDING occurs when one atom
donates an electron to another atom and
the resulting ions attract each other.
 COVALENT BONDING occurs when
atoms share electrons
ORGANIC VERSUS INORGANIC
 Organic compounds are composed of
molecules that contain Carbon-Carbon
(C-C) covalent bonds or CarbonHydrogen (C-H) bonds. Few inorganic
compounds contain carbon atoms and
none contain Carbon-Carbon or CarbonHydrogen bonds.
 Organic molecules are generally larger
and more complex .
Solvent and Solute
 SOLVENT is a substance in which other
substances are dissolved; for example, In
saltwater the water is the solvent
 SOLUTE is substance that dissolves into
another substance; for example In
saltwater the salt is the solute dissolved
in water.
TYPES OF INORGANIC
MOLECULES
 Water
 Acids
 Bases
 Salts
Concepts related to PH level
 PH is a unit expressing relative H+ (hydrogen)
concentration
 Formula used to calculate PH units gives a
value of 7 to pure water therefore 7 is a neutral
value neither acidic or basic
 PH values higher than 7 is basic
 PH values lower than 7 is acidic
 Normal body function can be maintained only
within a narrow range of PH. Normal range
7.35-7.45
Acid – Base Concepts
 Acid is any substance that when
dissolved in water, contributes to an
excess of H+ (hydrogen) ions. A lower
PH value indicates a higher H+
concentration –acidic Normal range 7.35
to 7.45
 Base is any substance that when
dissolved in water, contributes to an
excess of OH- (hydroxide) ion.
TYPES OF ORGANIC
MOLECULES
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Carbohydrates
Lipids
Triglycerides
Phospholipids
Cholesterol
Proteins
Nucleic Acids
deoxyribonucleic acid (DNA)
ribonucleic acid (RNA)
Carbohydrate Structure and
Function
 Monosaccharide (glucose, galactose, fructose
) single monosaccharide unit. Utilized as a
primary source of energy and to build other
carbohydrates
 Disaccharide (sucrose, lactose, maltose ) two
monosaccharide units. Broken into a
monosaccharide for energy
 Polysaccharide (glycogen, starch) many
monosaccharide units. Used to store
monosaccharides (thus to store energy)
Lipid Structure and Function
 Triglycerides are formed by one glycerol unit
and three fatty acids. Utilized to store energy in
cells
 Phospholipids are formed by two fatty acids
and a phosphorus containing unit. Utilized to
form a stable foundation for the cell membrane
 Cholesterol has four carbon rings at core.
Assists in stabilizing the cell membrane and is
the basis of steroid hormones
Protein Structure and Function
 Structural proteins (fibers) are amino
acids that form essential structures of the
body
 Functional proteins (enzymes, and
hormones) are amino acids that facilitate
chemical reactions; send signals ;
compose some of the hormones cell
membrane channels and receptors and
enzymes
Nucleic Acid Structure and
Function
 Nucleic acids are made from nucleotides. Each
nucleotide consists of a phosphate unit, a sugar unit
and a nitrogen base.
 Deoxyribonucleic acid (DNA) nucleotide base
includes adenine, thymine, guanine, and cytosine.
Contains information (genetic code) for making
proteins
 Ribonucleic acid (RNA) nucleotide base includes
adenine, uracil, guanine, and cytosine Serves as a
copy of a portion of the genetic code