Download Anatomy and Physiology Chapter #2 - Ms. Schwab

BASIC
CHEMISTRY
Chapter 2 – Advanced Human Anatomy
Introduction

Chemistry is the branch of science that
considers the composition of matter and how
this composition changes.

Chemistry is essential for understanding
anatomy and physiology because body
structures and functions result from
chemical changes within cells.
Structure of Matter
Matter is anything that has
mass (weight) and takes up
space.
 Matter is found in various
forms: gases, liquids, and solids

 Elements
make up all matter.
 Elements are composed of tiny
particles called atoms.
 Atoms are the smallest unit of
matter
Atomic Structure


Nucleus is the central
portion of the atom
which contains
neutrons (neutral) and
protons (positive).
Electrons: found
outside the nucleus in
energy shells (orbitals);
negative charge.
Drawing atoms


Atomic number is the number of
protons in an element.
The number of protons in the
nucleus of an atom equal the
number of electrons in its shells.


Atoms are neutral
Electron shells or orbitals:


1st shell can hold a max of 2
electrons
2nd – 6th shells can hold a max of
8 electrons
Drawing atoms continued…

Atomic mass = the
number of protons plus
neutrons.
 Therefore…
 atomic mass minus
atomic number equals #
of neutrons.
Atoms want Stability

The defining
characteristic of
stable elements is the
maximum number of
electrons in its
valence (outer) shell.

Unstable elements
achieve stability by
gaining, losing, or
sharing electrons in
their energy levels or
shells.
Bond Types

Ionic bonds occur between a metal and
nonmetals when they transfer electrons forming
ions.


Atoms that gain or lose electrons and become
electrically charged
Charged atoms = ions
Covalent bond between two nonmetals they
share electrons.
 Hydrogen Bonds: electromagnetic attractive
interaction between polar molecules, in which
hydrogen is bound to a highly electronegative
atom, such as nitrogen or oxygen.

Molecules and Compounds



A molecule is formed when
two or more atoms combine.
If atoms of different elements
combine, the resulting
structure can also be called a
compound. Examples: Baking
soda, sugar
Molecular formula represents
the numbers and types of
atoms in a molecule.
Examples… H2O & C6H12O6
Chemical Reactions
Synthesis when two or more atoms or
reactants bond to form a new, more
complex structure.





Synthesis requires energy and is important to the
growth of body parts.
A + B  AB
AB  A + B
Decomposition the opposite of
synthesis
Single Replacement: A single free
element replaces or is substituted for one AB + C  AC + B
of the elements in a compound
Double Replacement: reaction type can AB + CD  AD + CB
be viewed as an "exchange of partners."
Reaction Speed

Catalysts affect the speed of a reaction
 Many reactions occur to slowly to sustain
 Not consumed
by the reaction.
 Biological catalysts?
Enzymes!

life
Acids and Bases


pH scale ranges from 0 to 14. It indicates how
the concentration of H+ in a substance
Acids have pH less than 7
 More


H+ than OH-
Neutral pH equal to 7
Bases have pH greater than 7
 More
OH- than H+
ORGANIC AND
INORGANIC
COMPOUNDS
Day 2 – Basic Chemistry (Chapter 2)
Organic vs. Inorganic
2 types of chemicals

Organic
must contain carbon and
hydrogen but may contain other elements
as well. (C6H12O6)
Inorganic all the other compounds that
do NOT contain carbon-hydrogen
bonds; (H20)

Inorganic
Compounds
Water: plays an important role in dissolving solid
substances, moving chemicals around the body, and
absorbing and moving heat



Oxygen: Releases energy from glucose and other
nutrients.



Most abundant compound in cells and is a solvent in which
chemical reactions occur.
Polar molecule
This energy drives metabolism!
Carbon Dioxide: inorganic substances that is a
metabolic waste product, exhaled from the lungs.
Salts: provide a variety of ions that metabolic
processes require.
Organic Compounds




Carbohydrates
Lipids
Proteins
Nucleic acids
Carbohydrates
Supply most of the energy needed by cells

Composed of what 3 elements?



Building blocks = sugars




Carbon, Hydrogen, Oxygen
Monosaccharides (simple sugars)
Disaccharides are two sugars joined together
Polysaccharides, such as starch, are built of many sugars.
Humans synthesize the complex carbohydrate called
glycogen.

Type of condensation reaction in which
monomers (monosaccharides) join
together into polymers while losing a water
molecule
 This process is carried out by losing
(-OH) from one of the monomers and
(H) from another.

Lipids = concentrated energy molecules

Building block (monomer) = fatty acid

Not soluble in water

Common Categories
Fats
 Oils
 Waxes


energy storage
 very
concentrated
 2x the energy as carbohydrates!


cell membrane
cushion
 Organs
 Nerve cells

insulates body
 Whale
blubber!
Saturated vs. Unsaturated



Saturated = single carbon bond,
maximum # of hydrogen bonds
Unsaturated = carbon-carbon
double bond
Polyunsaturated = more than one
carbon-carbon double bond
Fat molecule is not a polymer, just a big “fat”
molecule.
Proteins

Proteins have many of functions in the body---as
structural materials, as energy sources, as certain
hormones, as receptors on cell membranes, as
antibodies, and as enzymes

Building blocks of proteins are the amino acids (20)


Give their identity by their R-Group
Link up to form chains – these chains become proteins!
amino acid
amino acid
amino acid
amino acid
amino acid

Amino Acids are
composed of:
Amino group
Carboxyl group
Hydrogen
R-group
Amino Acids
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Alanine
Glutamic acid
Leucine
Serine
Arginine
Glutamine
Lysine
Threonine
Asparagine
Glycine
Methionine
12. Tryptophan
13. Aspartic acid
14. Histidine
15. Phenylalanine
16. Tyrosine
17. Cysteine
18. Isoleucine
19. Proline
20. Valine
(NOTE: the 8 essential amino
acids are in blue. These
cannot be synthesized by the
human body and must be
obtained from food)
Protein Shapes




Proteins have complex
shapes held together by
hydrogen bonds. (their
many shapes changes
their functions)
Their complex shapes are
known as
conformations
Protein shapes can be
altered by pH,
temperature, radiation, or
chemicals.
When the H bonds break
this is called denaturing
Enzymes
Some chemical reactions are too slow or have activation
energies way too high so we need a….
: speeds up reaction and lowers the
activation energy

: biological catalysts! Enzymes are PROTEINS.
 Found
in cells
Enzyme-Substrate Complex

Enzymes provide a site where reactants can be
brought together to react

Reactants in an enzyme reaction are called substrates


Enzyme and the substrate fit together a bit like a puzzle!
Active site: place where substrate and enzyme bind

Once the reaction is over, products are released and the enzyme is
free to start the process over again
Induced-Fit model: This model proposes that the
initial interaction between enzyme and substrate is
relatively weak, but that these weak interactions
rapidly cause shape changes in the enzyme that
strengthen binding
 Enzyme changes shape during the reaction
Nucleic Acids

Nucleic acids form genes and take
part in protein synthesis.
 Contain
the elements C,H,O,N,P
 The building blocks are nucleotides.

Two major types: DNA (with
deoxyribose) and RNA (with
ribose).
DNA & RNA
Deoxyribonucleic acid: DNA
(deoxyribonucleic acid) stores the
molecular code in genes.
 How
many strands does it have?
Ribonucleic acid: RNA (ribonucleic
acid) functions in protein synthesis.
 How
many strands does it have?
Building block of nucleic acids – Nucleotides
 Nucleotides consist of 3 parts:
 Five carbon sugar
 Phosphate group
 Nitrogenous base
N base

sugar
phosphate