Transcript A Review Of Chemical And Physical Principles For Human Physiology

A Review Of Chemical And
Physical Principles For Human
Physiology
This review is provided as a basic
minimum coverage of the physical
and chemical organization of matter
in living systems
The Atomic Theory
• All matter consists of tiny particles called
atoms
• Atoms are, in turn, made up of three
fundamental particles, protons, neutrons,
and electrons
THE CARBON ATOM
+ PROTON
NEUTRON
-
ELECTRON
ORBIT
OR
SHELL
NUCLEUS
ATOMIC STRUCTURE
• PROTONS AND NEUTRONS ARE IN
THE NUCLEUS
• ELECTRONS ARE IN ORBITS AROUND
THE NUCLEUS
• THERE ARE EQUAL NUMBERS OF
PROTONS AND ELECTRONS
THE CARBON ATOM
There are 6 protons, 6 electrons, and 6 neutrons in this atom
NUCLEUS
ORBIT
OR
SHELL
ATOMIC MASS
• PROTONS AND NEUTRONS ARE FAR
MORE HEAVY THAN ELECTRONS
• THE UNIT OF ATOMIC MASS IS THE
MASS OF A PROTON OR NEUTRON
• CARBON HAS AN ATOMIC MASS OF
12, THE TOTAL OF PROTONS PLUS
NEUTRONS
ATOMIC NUMBER
• ATOMIC NUMBER OF AN ELEMENT IS
THE NUMBER OF PROTONS N THE
NUCLEUS
• THE ATOMIC NUMBER IDENTIFIES
THE ELEMENT AND DISTIGUISHES IT
FROM ALL OTHER ELEMENTS
• THUS CARBON IS THE ELEMENT
WITH ATOMIC NUMBER 6
THE CARBON ATOM
CARBON HAS ATOMIC NUMBER 6 AND ATOMIC
WEIGHT 12
There are 6 protons, 6 electrons, and 6 neutrons in this atom
NUCLEUS
ORBIT
OR
SHELL
CHARACTERISTICS OF
SELECTED ELEMENTS
Name
Hydrogen
Carbon
Nitrogen
Oxygen
Sodium
Magnesium
Phosphorous
Sulfur
Chlorine
Potassium
Calcium
Symbol
H
C
N
O
Na
Mg
P
S
Cl
K
Ca
# Protons
1
6
7
8
11
12
15
16
17
19
20
Atomic
Number
1
6
7
8
11
12
15
16
17
19
20
Atomic
Weight
(amu)
1.01
12.01
14.01
16.00
22.99
24.31
30.97
32.06
35.45
39.10
40.08
Chemical Bonds and Chemical
Compounds
• The shells or orbits which contain the
electrons have characteristic occupancy
capacity
• The first three are 2, 8, and 8 respectively
• Atoms tend to combine chemically forming
either ionic or covalent bonds so that the
outer orbits are complete
THE IONIC BOND
SODIUM HAS AN EXCESS ELECTRON, CHLORINE LACKS ONE
Na
Cl
THE IONIC BOND
ORBITS BECOME COMPLETE BY DONATION OF AN ELECTRON
Na
POSITIVE ION
Cl
NEGATIVE ION
THE COVALENT BOND
ORBITS BECOME COMPLETE BY SHARING ELECTRONS
H
H
C
H
H
H
=
H
C
H
H
CHEMICAL REACTIONS
PROCESSES IN WHICH CHEMICAL BONDS ARE FORMED
OR BROKEN ARE CALLED CHEMICAL REACTIONS
CH4 + 2O2
CO2 + 2H2O
ENZYMES
• ENZYMES ARE BIOLOGICAL
CATALYSTS
• CATALYSTS MAKE REACTIONS GO
FASTER
• THEIR NAMES USUALLY END IN
“ASE”
• EXAMPLES: ATPASE, KINASE,
OXIDASE, ETC.
MOLECULAR WEIGHTS
• THE MOLECULAR WEIGHT IS THE
SUM OF THE ATOMIC WEIGHTS OF
THE CONSTITUENTS OF THE
MOLECULE
• EXAMPLE: WATER (H2O), THE
MOLECULAR WEIGHT IS 16 + 1.01
+1.01= 18.02 ATOMIC MASS UNITS
THE MOLE
• THE WEIGHT IN GRAMS EQUIVALENT
TO THE ATOMIC OR MOLECULAR
WEIGHT IN ATOMIC MASS UNITS
• A MOLE OF WATER HAS A WEIGHT OF
18.02 GRAMS
• A MOLE OF ANY SUBSTANCE
CONTAINS AVAGADRO’S NUMBER OF
PARTICLES (6.02 x 1023)
SOLUTIONS
• A SOLUTION IS A HOMOGENEOUS
MIXTURE
• IT CONTAINS A RELATIVELY LARGE
AMMOUNT OF ONE SUBSTANCE,
CALLED THE SOLVENT
• IT MAY CONTAIN ANY NUMBER OF
SOLUTES IN A FAR LESSER
QUANTITY
WATER AS SOLVENT
• WATER IS THE UNIVERSAL
BIOLOGICAL SOLVENT
• WATER HAS UNIQUE PROPERTIES
UNEQUALED IN NATURE
• WATER IS A POLAR COMPOUND AND
IS A GOOD SOLVENT FOR IONS
• WATER DOES NOT MIX WITH
NONPOLAR SUBSTANCES SUCH AS
OILS
ELECTROLYTE SOLUTIONS
METAL SALTS FORM IONS UPON DISSOLVING
IN WATER
NaCl
CaCl2
Na+ + Cl-
Ca+ + 2Cl-
MACROMOLECULES
• LARGE MOLECULES CAN BE
FORMED WITH COVALENT BONDS
BETWEEN SMALLER SUBUNITS
• IN CHEMISTRY THESE ARE CALLED
POLYMERS
BIOLOGICAL MOLECULES
•
•
•
•
•
CARBOHYDRATES
LIPIDS
PROTEINS
NUCLEIC ACIDS
HIGH ENERGY BIOMOLECULES (ATP)
FUNCTIONAL GROUPS
• ORGANIC COMPOUNDS ARE
CLASSIFIED IN TERMS OF REACTIVE
PARTS OF THE MOLECULES CALLED
FUNCTIONAL GROUPS
• ONE IMPORTANT FUNCTIONAL
GROUP IS THE ORGANIC ACID
ACIDS, BASES AND SALTS
• CHEMICAL COMPOUNDS CAN BE
PROTON DONORS OR ACCEPTORS
• PROTON DONORS ARE ACIDS
• PROTON ACCEPTORS ARE BASES
• ACIDS AND BASES REACT TO
NEUTRALIZE EACH OTHER FORMING
SALTS
ACID/BASE REACTIONS
HCl + NaOH
NaCl + H2O
ACID + BASE
SALT + WATER
CARBOHYDRATES
• CONTAIN C, H AND O (nCH2O)
• SIMPLE SUGARS ARE
MONOSACCHARIDES (GLUCOSE,
GALACTOSE, FRUCTOSE)
• SUGARS FORM POLYMERS: STARCH
OR GLYCOGEN (USUALLY A
STORAGE FORM)
• SIMPLE SUGARS ARE WATER
SOLUABLE
LIPIDS
•
•
•
•
•
FATTY ACIDS
TRIGLYCERIDES
PHOSPHOLIPIDS
STEROIDS
CHOLESTEROL
PROTEINS
• POLYMERS MADE FROM 20 AMINO
ACIDS JOINED IN PEPTIDE BONDS
• MANY IMPORTANT BIOLOGICAL
FUNCTIONS INCLUDING ENZYMES
• THE RESULT OF THE GENETIC CODE
IN DNA
PROTEIN STRUCTURE
• PRIMARY: THE SEQUENCE OF AMINO
ACIDS CODED IN DNA
• SECONDARY: FOLDING INTO
HELICAL OR SHEET STRUCTURES
DUE TO HYDROGEN BONDING AND
OTHER FACTORS
• TERTIARY: SIDE CHAINS INTERACT
• QUATENARY: AGGREGATES FORM
NUCLEIC ACIDS
• DNA: A DOUBLE HELIX FORMED BY
TWO POLYMERS OF NUCLEIC ACIDS
• RNA: A SINGLE POLYMER OF
NUCLEIC ACID
• COMPLEMENTARY PAIRS OF
NUCLEIC ACIDS ENABLE
MOLECULES TO DUPLICATE OR COPY
EACH OTHER, THE BASIS FOR THE
GENETIC CODE
ENERGY CURRENCY
ATP, ADENOSINE TRIPHOSPHATE,
IS A HIGH ENERGY COMPOUND
WHICH STORES AND TRANSFERS
ENERGY
A-P-P - P
A-P-P + P + ENERGY