Biology 101 Survey of Biology, Fall 2008
Instructor: Dr. Kurt Toenjes,
Phone: 896-5940
Room: 133 Science Hall
Email: ktoenjes@msubillings.edu
Textbook: BIOLOGY. Concepts and Connections, 6th Edition by Neil Campbell et al.
•Course Introduction and Objectives:
•Assessment:
•Grading:
•Academic Honesty:
•Attendance:
•Schedule:
The Importance of Biology
The Importance of Biology
The Importance of Biology
The Importance of Biology
The Importance of Biology
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
• The biosphere is the total of all of Earth’s ecosystems
– The biosphere
• Is the global ecosystem
Figure 34.2A
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
Loss of Heat energy
Sun
Air
Inflow
of
light
energy
O2
CO2
•An ecosystem consists of all the
organisms living in a particular
area plus the non-living
components
CO2
Chemical
energy
Producers
Cycling of
Chemical
nutrients
Consumers
Decomposers
H2O
Soil
Ecosystem
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
•An individual living entity is an organism
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
•An individual living entity is an organism
•An organism has organ systems containing
organs that are made up of different tissues.
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
•An individual living entity is an organism
•An organism has organ systems containing
organs that are made up of different tissues.
•The tissues are made of of different cells.
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
•An individual living entity is an organism
•An organism has organ systems containing
organs that are made up of different tissues.
•The tissues are made of of different cells.
•Cells consist of a combination of organelles
and organelles consist of molecules.
THE SCOPE OF BIOLOGY
Life’s levels of organization define the scope of biology
•An ecosystem consists of all the organisms
living in a particular area plus the non-living
components
•A population consists of a localized group of
individuals of a species
•An individual living entity is an organism
•An organism has organ systems containing
organs that are made up of different tissues.
•The tissues are made of of different cells.
•Cells consist of a combination of organelles
and organelles consist of molecules.
The diversity of life can be arranged into three
domains
Figure 1.5B
SEM 25,000!
Figure 1.5A
SEM 3,250!
• Organisms are grouped (classified) into the prokaryotic domains
of Bacteria and Archaea and the eukaryotic domain Eukarya :
The diversity of life is arranged into three
domains
– Domain Eukarya includes
• Protists (protozoans and algae, falling into multiple
kingdoms)
• The kingdoms Fungi, Plantae, and Animalia
The diversity of life is further organized
The unity of life: All forms of life have common
features
– Ordered structures
– Regulation of internal conditions
– Growth and development
– Energy use
– Response to environmental
stimuli
– The ability to reproduce and
evolve
Figure 1.4D
Figure 1.4E
All forms of life also have common components
Figure 1.4B
Figure 1.4C
•
•
•
•
•
DNA
RNA
Proteins
Lipids
Carbohydrates
The Importance of Biology
Scientists use two main approaches to learn
about nature
• Discovery Science
• Scientists describe some aspect of the world and use
inductive reasoning to draw general conclusions
• Hypothesis-Based Science
• Scientists attempt to explain
observations by testing hypotheses
Scientists use two main approaches to learn
about nature
• With hypothesis-based science, we pose and test
hypotheses
• We formulate observations, questions, hypotheses as
tentative answers to questions
• Deductions then lead to predictions
• Predictions are tested to see if a hypothesis is falsifiable
Scientists use two main approaches to learn
about nature
Deductive reasoning is used in
testing hypotheses as follows
•
If a hypothesis is
correct, and we test it,
then we can expect a
particular outcome
Observations
Question
Hypothesis # 1:
Dead batteries
Hypothesis # 2:
Burnt-out bulb
Prediction:
Replacing batteries
will fix problem
Prediction:
Replacing bulb
will fix problem
Test prediction
Test prediction
Test falsifies hypothesis
Test does not falsify hypothesis
Scientists use two main approaches to learn
about nature
Deductive reasoning is used in
testing hypotheses as follows
•
If a hypothesis is
correct, and we test it,
then we can expect a
particular outcome
Observations
Question
Hypothesis # 1:
Dead batteries
Hypothesis # 2:
Burnt-out bulb
Prediction:
Replacing batteries
will fix problem
Prediction:
Replacing bulb
will fix problem
Test prediction
Test prediction
Test does not falsify hypothesis
Test falsifies hypothesis
A Case Study of Hypothesis-Based Science
– In experiments designed to test hypotheses
Figure 1.8B
The use of control groups and experimental groups
helps to control variables
Figure 1.8C
Percent of total attacks
on artificial snakes
•
100
80
83%
84%
Artificial brown snakes
60
40
20
17%
16%
0
Coral snakes Coral snakes
present
absent
Figure 1.8D
Artificial king snakes
Theory: Scientific versus general
Theory: Scientific versus general
In one episode of 'Cheers', Cliff is seated at the bar describing the Buffalo Theory to
Norm. "Well you see, Norm, it's like this... A herd of buffalo can only move as
fast as the slowest buffalo. And when the herd is hunted, it's the slowest and
weakest ones at the back that are killed first. This natural selection is good for
the herd as a whole, because the general speed and health of the whole group
keeps improving by the regular killing of the weakest members.”
1.
A set of statements or principles devised to explain a
group of facts or phenomena, especially one that has been
repeatedly tested or is widely accepted and can be used to
make predictions about natural phenomena.
Theory: Scientific versus general
In one episode of 'Cheers', Cliff is seated at the bar describing the Buffalo Theory to
Norm. "Well you see, Norm, it's like this... A herd of buffalo can only move as
fast as the slowest buffalo. And when the herd is hunted, it's the slowest and
weakest ones at the back that are killed first. This natural selection is good for
the herd as a whole, because the general speed and health of the whole group
keeps improving by the regular killing of the weakest members.”
“In much the same way, the human brain can only operate as fast as the
slowest brain cells. Now, as we know, excessive intake of alcohol kills brain cells.
But naturally, it attacks the slowest and weakest brain cells first. In this way,
regular consumption of beer eliminates the weaker brain cells, making the brain a
faster and more efficient machine. And that, Norm, is why you always feel
smarter after a few beers...."
1.
A set of statements or principles devised to explain a
group of facts or phenomena, especially one that has been
repeatedly tested or is widely accepted and can be used to
make predictions about natural phenomena.
2.
An assumption based on limited information or knowledge;
a conjecture.e; a conjecture.
Theory: Scientific versus general
Cell theory
Theory: Scientific versus general
Stem Cell theory
Theory: Scientific versus general
Stem Cell use in wound repair
Theory: Scientific versus general
Stem Cell use in wound repair
Theory: Scientific versus general
Stem Cell use in wound repair
Debate is an important part of science
Not a current scientific debate
• Natural selection and evolution versus Creative Design
Not a current scientific debate
• Natural selection and evolution versus Creative Design
Review
•Life is organized through their similarities and differences
•Scientists use two main approaches to learn about nature:
Discovery and Hypothesis based
•Debate is an important part of Science
ELEMENTS, ATOMS, AND MOLECULES
Living organisms are composed of about 25 chemical elements that are
essential to life.
ELEMENTS, ATOMS, AND MOLECULES
ELEMENTS, ATOMS, AND MOLECULES
The trace elements are present in very small amounts and yet are very
important to to life.
Dietary deficiencies in trace mineral can cause disease.
Examples:
Iodine (I) --Thyroid disease
Fluoride (F) -- dental disease
Selineum (Se) -- immune deficiencies, thyroid disease,
cancer,
ELEMENTS, ATOMS, AND MOLECULES
How do we meet our dietary requirements for trace elements?
The smallest particle of matter that still retains the
properties of an element is an atom
An atom is made up of protons, neutrons, and electrons
Each type of atom (element) has a specific number of protons
–
–
2e–
Electron
cloud
+
+
+
+
Nucleus
2 +
Protons
2
Neutrons
2 –
Electrons
Mass
number = 4
The number of neutrons in an atom may vary.
Different forms of an element are called isotopes
Some isotopes are radioactive (unstable)
Radioactive isotopes can help or harm us
Radioactive isotopes are useful as tracers in combination
with medical imaging techniques in the diagnosis of disease.
Radioactive isotopes can help or harm us
Radioactive isotopes are also used in:
Treatment of tumors
Biochemistry
Genetics
Food preservation
Agriculture
Industry
Enviormental studies
Radioactive isotopes can help or harm us
The hazards to people and the environment from radioactive
contamination depend on the nature of the radioactive
contaminant, the level of contamination, and the extent of
the spread of contamination
Radiation sickness results from damage to the DNA of
organic tissue.
Some radioisotopes may target specific organs
The thyroid gland takes up a
large percentage of any iodine
that enters the body.
Radioactive iodine was a major
component of the radiation released from
the Chernobyl disaster, leading to many
cases of pediatric thyroid cancer and
hypothyroidism.
Radioactive iodine is also used in the diagnosis and
treatment of many diseases of the thyroid precisely
because of the thyroid's selective uptake of iodine.
Elements can combine to form compounds
Sodium
Chlorine
Sodium Chloride
Na
Cl
NaCl
cation
anion
Inorganic salt
The smallest particle of matter that still retains the
properties of an element is an atom
An atom is made up of protons, neutrons, and electrons
Each type of atom (element) has a specific number of protons
–
–
2e–
Electron
cloud
+
+
+
+
Nucleus
2 +
Protons
2
Neutrons
2 –
Electrons
Mass
number = 4
The smallest particle of matter that still retains the
properties of an element is an atom
An atom is made up of protons, neutrons, and electrons
Each type of atom (element) has a specific number of protons
–
–
2e–
Electron
cloud
+
+
+
+
Nucleus
2 +
Protons
2
Neutrons
1 –
Electrons
Mass
number = 4
Charge is positive: cation
The smallest particle of matter that still retains the
properties of an element is an atom
An atom is made up of protons, neutrons, and electrons
Each type of atom (element) has a specific number of protons
–
–
2e–
Electron
cloud
+
+
+
+
Nucleus
2 +
Protons
2
Neutrons
3 –
Electrons
Mass
number = 4
Charge is negative: anion
The number of electrons and their arrangement
in an atom will vary.
The number and arrangement of electrons determines whether
the atom will interact with other atoms and form chemical bonds.
When electrons are lost or gained, charged atoms are created
(ions).
When positively
charged ions interact
with negatively
charged ions, ionic
bonds are created.
The number of electrons and their arrangement
in an atom will vary.
When electrons are shared between two atoms covalent bonds
are formed
The number of electrons and their arrangement
in an atom will vary.
Electrons are often shared unequally between atoms,
creating a polar molecule.
(–)
Water is a polar
molecule.
(–)
O
H
H
(+)
(+)
The number of electrons and their arrangement
in an atom will vary.
When electrons are shared between two atoms covalent bonds
are formed and electrons are shared unequally between atoms, a
polar molecule is created (water).
The charged regions on polar
molecule (water) are
attracted to the oppositely
charged regions on nearby
molecules. This interaction
between polar molecules are
called hydrogen bonds
because hydrogen atoms are
always involved in this type of
bond.
Hydrogen
(–)
bond
(+)
H
(+)
O
(–)
(–)
(+)
H (
+
)
(–)
Liquid water is formed through hydrogen bonds
The strength of the hydrogen bonds between water
molecules enables:
Water to travel from the roots of a plant to the
highest leaves
Liquid water is formed through hydrogen bonds
The strength of the hydrogen bonds between water
molecules enables:
Water to travel from the roots of a plant to the
highest leaves
Insects to walk on water
Liquid water is formed through hydrogen bonds
The strength of the hydrogen bonds between water
molecules enables:
Water to travel from the roots of a plant to the
highest leaves
Insects to walk on water
A water drop to form
Liquid water is formed through hydrogen bonds
The strength of the hydrogen bonds between water
molecules enables:
Water to travel from the roots of a plant to the
highest leaves
Insects to walk on water
A water drop to form
A belly flop to hurt
The hydrogen bonds of water enable water to store
heat.
It takes a lot of energy to disrupt hydrogen bonds so
water is able to absorb a great deal of heat energy
without a large increase in temperature.
Hydrogen
(–)
bond
(+)
H
(+)
O
(–)
H (
+
)
(–)
(+)
(–)
The hydrogen bonds of water enable water to store
heat.
It takes a lot of energy to disrupt hydrogen bonds so
water is able to absorb a great deal of heat energy
without a large increase in temperature.
HEAT
X
(–)
Hydrogen
bond
(+)
H
X
(+)
O
(–)
X X
(–)
(+)
H (
+
)
(–)
The hydrogen bonds of water also allow ice to float
Hydrogen bond
Ice
Hydrogen bonds are stable
Liquid water
Hydrogen bonds
constantly break and re-form
Water is the solvent of life
Polar or charged solutes Dissolve when water
molecules surround them, forming aqueous solutions
The chemistry of life is sensitive to acidic and
basic conditions, pH.
H+
H+
Acidic solution
OH–
OH–
OH–
H+ H+ –
OH– OH
H+ H+ H+
Neutral solution
A compound that
accepts H+ ions in
solution is a base
OH–
OH–
OH– H+ OH–
–
OH OH– –
OH
H+
Increasingly ACIDIC
(Higher concentration of H+)
+
H+ H
H+ OH– H+
OH– H+ H+
NEUTRAL
[H+]=[OH–]
Increasingly BASIC
(Lower concentration of H+)
A compound that
releases H+ ions in
solution is an acid
pH scale
0
1
2
Lemon juice, gastric juice
3
Grapefruit juice, soft drink
4
Tomato juice
5
6
Human urine
7
Pure water
Human blood
8
Seawater
9
10
Milk of magnesia
11
Household ammonia
12
Household bleach
13
Oven cleaner
14
Basic solution
The chemistry of life is sensitive to acidic and
basic conditions, pH.
H+ H+
Acidic solution
•The pH of most cells is
kept close to 7 (neutral)
by buffers
OH–
OH–
OH–
H+ H+ –
OH– OH
H+ H+ H+
Neutral solution
OH–
OH–
OH– H+ OH–
–
OH OH– –
OH
H+
Basic solution
NEUTRAL
[H+]=[OH–]
Increasingly BASIC
(Lower concentration of H+)
+
H+ H
H+ OH– H+
OH– H+ H+
Increasingly ACIDIC
(Higher concentration of H+)
pH scale
0
1
2
Lemon juice, gastric juice
3
Grapefruit juice, soft drink
4
Tomato juice
5
6
Human urine
7
Pure water
Human blood
8
Seawater
9
10
Milk of magnesia
11
Household ammonia
12
Household bleach
13
Oven cleaner
14
3.1 Life’s molecular diversity is based on the
properties of carbon
A carbon atom can form four covalent bonds
Allowing it to build large and diverse organic compounds
Structural
formula
Ball-and-stick
model
H
H
Space-filling
model
H
H
C
C
H
H
Methane
H
H
The 4 single bonds of carbon point to the corners of a tetrahedron.
Carbon chains vary in many ways
H
H H
C C
H
H
H H H
C C C
H
H H H
H H
Ethane
Propane
Carbon skeletons vary in length.
H
H C H
H H H H
H
H
H C C C C H
H C C C H
H H H
H H H H
Butane
Isobutane
Skeletons may be unbranched or branched.
H H H H
C
C C C H
H
H
H H
H
1-Butene
2-Butene
Skeletons may have double bonds, which can vary in location.
H
H H H H
C C C C H
H
H
H
C
H
H C C
H
H
C
H C
C H
H
C
C H
H C C C H
H
H
C
H
H
H
Benzene
Cyclohexane
Skeletons may be arranged in rings.
Hydrocarbons are composed of only hydrogen and carbon
Functional groups help determine the properties of
organic compounds
– Functional groups are particular groupings of atoms
•
That give organic molecules particular properties
OH
O
The four main classes of biological molecules are
•
•
•
•
carbohydrates,
lipids,
proteins
nucleic acids
Monosaccharides are the simplest carbohydrates
The monosaccharides glucose and fructose are
isomers.
H
O
H
C
C
OH
C
O
HO
C
H
H
H
C
OH
HO
C
H
H
C
OH
H
C
OH
H
C
OH
H
C
OH
H
C
OH
H
C
OH
H
Glucose
H
Fructose
Monosaccharides can also occur as ring structures
Glucose
O
H
C
CH2OH
H
C
OH
HO
C
H
H
H
C
OH
HO
H
C
OH
H
C
OH
O
H
OH
H
H
OH
ring structure
H
Linear structure
H
O
OH
Simplified
structure
Cells link two single sugars (Monosaccharides) to
form disaccharides.
CH2OH
O
H H
OH
HO
CH2OH
O
H H
H
H
H
OH
Glucose
HO
OH
H OH
Glucose
H2O
CH2OH
CH2OH
H H
H
OH
HO
OH
H
O
OH
H
H
OH
H
H
O
O
H
H
OH
H
H
OH
OH
Maltose
Cells link two single sugars (Monosaccharides) to
form disaccharides.
Cells link two single sugars (Monosaccharides) to
form disaccharides.
Cells make most of their large molecule by joining
smaller organic molecules into chains called
polymers by a dehydration reaction.
H
OH
OH
Short polymer
OH
H
H
Unlinked monomer
Dehydration
Dehydration
reaction
reaction
H
H
H2O
OH
OH
Longer polymer
Polymers are broken down to monomers by the
reverse process, hydrolysis.
H2O
H
OH
Hydrolysis
H
OH
OH
H
Starch and glycogen are polysaccharides that store sugar
for later use
Cellulose is a polysaccharide found in plant cell walls
Glucose
monomer
STARCH
Starch granules in
potato tuber cells
O O
O
O
O
O
O
O
O
O
Glycogen
granules in
muscle
tissue
GLYCOGEN
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O O
Cellulose fibrils in a
plant cell wall
Cellulose
molecules
O
O
CELLULOSE
O
O
O
O
O
O
O
O
O
O
The orientation of the bond connecting the glucose
monomers is different between starch and cellulose
STARCH
CELLULOSE
Lipids
•Fats are lipids that are mostly energy-storage molecules
•Lipids are diverse compounds that consist mainly of carbon
and hydrogen atoms linked by nonpolar covalent bonds
C O
CH2
CH2
CH2
CH2
CH2 Fatty acid
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH3
Fats, also called triglycerides, are lipids whose main
function is energy storage
Fats consist of glycerol linked to three fatty acids
H
H
H
H
C
C
C
O
C
O
O
C
H
O
O
C
O
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH3
CH3
CH
CH2
CH2
CH2
CH2
CH2
CH2
CH3
The trans fat debate
vs
The trans fat debate
There are different types of lipids with a variety of
functions
– Phospholipids are a major component of cell membranes
– Waxes form waterproof coatings
– Steroids are often hormones
H
O
Phosphate
Phospholipid
H
H
H
C
C
C
O
O
O
P
O C
O C
O
H
O
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH3
Fatty acid
CH
CH2
CH2
CH2
CH2
CH2
CH2
CH3
There are different types of lipids with a variety of
functions
– Phospholipids are a major component of cell membranes
– Waxes form waterproof coatings
– Steroids are often hormones
There are different types of lipids with a variety of
functions
– Phospholipids are a major component of cell membranes
– Waxes form waterproof coatings
– Steroids are often hormones
Steroids
There are different types of lipids with a variety of
functions
– Phospholipids are a major component of cell membranes
– Waxes form waterproof coatings
– Steroids are often hormones
Steroids
H3C
CH3
CH3
CH3
CH3
HO
Proteins
– Proteins are essential to the structures and activities of
life
– A protein is a polymer constructed from amino acid
monomers
– Proteins are made from amino acids linked by peptide
bonds
Proteins
Each protein has a different arrangement of a
common set of 20 amino acid monomers.
Proteins
Each amino acid contains
•
•
•
An amino group
A carboxyl group
An R group, which distinguishes each of the 20 different
amino acids
H
O
H
N
C
H
C
OH
R
Amino
group
Carboxyl (acid)
group
Proteins
Each amino acid contains
•
•
•
An amino group
A carboxyl group
An R group, which distinguishes each of the 20 different amino
acids
Each amino acid has specific properties
•
H
H
H
O
N
C
H
C
H
O
N
OH
CH2
H
H
C
H
C
CH
N
OH
CH2
O
C
H
OH
CH2
OH
C
CH3 CH3
OH
Leucine
(Leu)
Hydrophobic
C
Serine (Ser)
O
Aspartic acid
(Asp)
Hydrophilic
Proteins
Cells link amino acids together through peptide bonds
Carboxyl
group
Peptide
bond
Amino
group
O
N
C
R
Amino acid
O
+
OH
N
Dehydration
reaction
O
C
H
N
OH
R
Amino acid
H2O
C
C
O
N
C
R
R
Dipeptide
C
OH
Proteins
Cells link amino acids together through peptide bonds
Polypeptide
Protein
Groove
A protein’s shape depends on four levels of
structure
– primary structure
Leu
Met
Asn
Pro
Val
Cys
Gly
Gly
Thr
Glu
Ser
Lys
Lys
Ala
Val
Leu
Asp
Ala
Val
Arg
Amino acids
Gly
Pro
Ser
Val
Ala
Ile
Arg
Val
His
Phe
Val
A protein’s shape depends on four levels of
structure
– primary structure
– secondary structure
Amino acids
Alpha helix
Pleated sheet
A protein’s shape depends on four levels of
structure
– primary structure
– secondary structure
– tertiary structure
Groove
A protein’s shape depends on four levels of
structure
– primary structure
– secondary structure
– tertiary structure
– quaternary structure
Polypeptide
chain
Collagen
Nucleic acids
Nucleic acids are information-rich polymers
of nucleotides
DNA and RNA Serve as the blueprints for proteins and thus
control the life of a cell