Transcript Chapter 2: Basic Chemistry and Applications

Chapter 2: Basic Chemistry and Applications
I Concepts of matter and energy
A. Matter: Anything that occupies space
1. There are three states of matter, all of which are present
in your body:
a. Solid: tissues, cells, organs
b. Liquid: blood plasma and interstitial fluid (surrounds
all cells)
c. Gas: Air you breath, gases produced in large
intestine
B. Energy: Ability to do work or put matter into motion
1. Two forms:
a. Kinetic: energy is actually doing work (moving
matter, using muscles to lift and object)
b. Potential: Stored or inactive energy (like in an ATP
bond)
Chapter 2: Basic Chemistry and Applications
I
2. Types of energy:
a. Chemical energy: Stored in bonds, such as in high
energy foods
(complex carbohydrates); energy is
released when bond is broken.
b. Electrical energy: Movement of charged particles, such as
the
sodium/potassium pump used for nerve impulses.
c.Mechanical energy: Directly moves matter, such as muscles moving
a load.
d.Radiant energy: Traveling in waves, such as the light energy that
stimulates the retina in the back of your eye.
Chapter 2: Basic Chemistry and Applications
3. First law of thermodynamics: Energy can be neither created nor
destroyed, it only changes form.
a. Example from your body: ATP bond is broken to release
energy → which powers the muscle to contract→ some of
the energy is lost has heat (unusable) →you sweat (giving
off excess heat) as you exercise.
Chapter 2: Basic Chemistry and Applications
II
Composition of matter and therefore YOU!
A. All matter is made up of elements that cannot be broken
down into smaller particles by ordinary means.
B. The building block of an element is the atom
Composition of the atom:
Chapter 2: Basic Chemistry and Applications
C. Two or more atoms combined chemically are called a
molecule. If the atoms are of different elements, the term is
a compound.
1. Types of bonds that create molecules and compounds
(filling that outer shell)
a. Ionic: Electrons are transferred from one atom to
another atom; this creates ions (charged atom) which
are then attracted to each other. Compounds usually
form salts.
b. Covalent: Electrons are shared between the atoms.
1. Equally shared electrons orbiting compound =
Nonpolar molecule (ex. methane, Carbon dioxide)
Chapter 2: Basic Chemistry and Applications
2. Unequally shared electrons orbiting compound = Polar
molecule (ex. water)
3. Hydrogen bond: Weak bond between hydrogen (covalently
bonded to large atom) and another large electron hungry
atom of another molecule. Common between water
molecules. Also can help stabilize large molecules (such as
proteins).
Chapter 2: Basic Chemistry and Applications
D. Patterns of chemical reactions (making and breaking bonds)
1. Synthesis Reactions: Combining smaller molecules to
make larger more complex molecules. Ex. building
proteins
2. Decomposition Reactions: Breaking down larger
molecules into smaller components. Ex. digestion of
food or breaking down toxins/drugs
In the cartoon, the skinny
bird (reactant) and the worm
(reactant) combine to make
one product, a fat bird.
A
+
B
Synthesis Reaction
AB
---->
A
+
B
Decomposition Rection
---->
AB
Chapter 2: Basic Chemistry and Applications
III. Inorganic Compound
A. Special Properties of water: Why your 8 glasses a day are
Necessary
1. High heat capacity: Water can absorb and release large
amounts of heat without having a drastic effect on the
temperature of the water.
Ex. You can play sports on a hot day and your body
temperature remains relatively constant by heat
loss through your sweat.
2. Polar Molecule → Solvent Properties (dissolves salts, ions,
nutrients, gases, acids and bases)
a. Important for chemical reactions to occur in the body, rxn.
will not occur unless chemicals are dissolved (in water);
also important for transport (blood plasma)
b. Important for movement/lubrication/decrease friction
Chapter 2: Basic Chemistry and Applications
3. Chemical Reactivity: Important reactant in metabolic
processes such as digestion.
4. Cushioning: Important with CSF (cerebral-spinal fluid)
for cushioning brain and with amniotic fluid to protect fetus.
B. Salts & Acids and Bases: Electrolytes (dissociate and ionize
in water)
a. Salts: Compounds formed from ionic bonding.
Important for metabolic processes such as
sodium/potassium pump for conducting nerve
impulses; transport of oxygen by hemoglobin in red
blood cells.
Sodium/ Potassium Pump
b. Acid (proton donor) and Base (proton acceptor)
Acid- substance that releases H+ ions (1-6.9 pH scale)
Base- substance that release OH- ions (7.1-14)
Chapter 2: Basic Chemistry and Applications
i. Balance in the body is important for proper functioning. pH
differs in different places in the body. Ex. blood 7.4 (neutral) to
pH 2 (gastric juices)
ii. Buffers are present in the body to help maintain the proper pH
level. Buffers are weak acids and bases.
Chapter 2: Basic Chemistry and Applications
IV
Organic Compounds
A. Carbohydrates
1. Contain carbon, hydrogen and oxygen in a 1:2:1 ratio
2. Classified based on size:
a. Monosaccharides: 1 sugar (smallest unit); ex.
Glucose (blood sugar), fructose, galactose, ribose,
deoxyribose
b. Disaccharides: double sugars; ex. sucrose
(cane sugar), lactose (found in dairy), and maltose
(malt sugar)
c. Polysaccharides: many sugars (larges); insoluble
(used for storage) and lack sweetness. Ex.Glycogen
3. Main function: cellular energy (glucose is oxidized and
energy released is stored in ATP. If not used immediately,
will be stored as glycogen or fat.
4. Secondary function: Structural components of cells (1% to
2% of cells), surface proteins on membrane, component of
DNA and RNA.
Chapter 2: Basic Chemistry and Applications
IV Organic Compounds
B. Lipids
1. Contain: carbon, hydrogen, and oxygen (no set ratio)
2. Are non-polar compounds so they do not dissolve in water
3. 3 categories of lipids:
a. Neutral Fats: triglycerides
i. solid- saturated fats - animal fat
ii. liquid – unsaturated – plant oils
iii. Bodies most abundant source of usable
energy as well as shock absorber and
insulation.
b. Phospholipid: Similar to triglycerides with a
phosphorous containing group. Molecule has a
charged region for interacting with water and ions and
a fatty acid end (hydrophobic). Very important for
selective permeability of plasma membrane.
Chapter 2: Basic Chemistry and Applications
IV
Organic Compounds
c. Steroids: Have a ring structure and are fat soluble. Ex.
cholesterol found in cell membranes, used to form
vitamin D and some hormones.
C. Proteins
A. Accounts for 50% of your organic matter, made from amino
acids. Composed of carbon, hydrogen, oxygen, nitrogen
and sulfur.
B. Function and structure of a protein is linked to the sequence
of amino acids (controlled by genes). If the order of amino
acids changes the structure and function of that protein will
be altered. Ex. like our language, floor → flour
Chapter 2: Basic Chemistry and Applications
IV
Organic Compounds
c. Two structural types:
i. Fibrous (structural) proteins. Important for binding structures
and providing strength in body tissues. Ex. collagen (tendons,
cartilage and skin) and actin and myosin (make up muscles)
ii. Globular (mobile/functional) proteins. Involved in most body
processes. Ex. antibodies (fight disease), hormones (long
term regulation), transport proteins (hemoglobin) and
enzymes (catalyze chemical reactions).
D. Destruction of proteins/Denaturing Proteins
i. Fibrous proteins are very stable (not many hydrogen bonds
holding together an intricate structure). Globular proteins
have many hydrogen bonds and are very fragile
ii. Factors that denature (break hydrogen bonds) proteins alter the
active site that reacts with the substrate. Factors include
increased temperature, pH and/or salinity. Ex. why a high
fever is not healthy.
Chapter 2: Basic Chemistry and Applications
D. Nucleic Acids
a. Composed of nucleotides (phosphate group, sugar and
nitrogen base).
b. Two types:
i. DNA (deoxyribonucleic acid)-compose your genes which
are responsible for the basic organism blueprint as well
as growth and development. All done by dictating
protein structure!!
ii. RNA (ribonucleic acid)-carries out the orders of DNA
genes helping with transcription and translation of gene
information into proteins.
Chapter 2: Basic Chemistry and Applications
E. One more important molecule – ATP (adenosine triphosphate)
Molecule that stores chemical energy used by all your body
cells. Energy is stored in the high energy third phosphate
bond.