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Minimum Module A Review
Unit 1 Review
Bio Keystone Module A
BIO.A.1.1
• Explain the characteristics of life shared by all
prokaryotic and eukaryotic organisms.
What is shared by all living things?
• An organism is any individual living thing.
• Living things share some common characteristics:
1. All are made of one or more cells.
2. All need energy for metabolism.
• Metabolism: All of the chemical processes in
an organism that build up or break down materials.
3. All respond to their environment.
– Stimuli, or physical factors, include light, temperature,
and touch.
4. All have genetic material (DNA) that they pass on to
offspring.
Prokaryotic (no nucleus) & Eukaryotic (yes
nucleus) Cells share certain characteristics.
1. Cells tend to be microscopic.
2. All cells are enclosed by a plasma
membrane. AKA Cell Membrane
3. All cells are filled with cytoplasm.
4. All cells have ribosomes. (can make
proteins aka protein synthesis aka
translation).
5. All cells have hereditary material (DNA)
BIO.A.2.1
• Describe how the unique properties of water
support life on Earth.
• - Describe the unique properties of water and
how these properties support life on Earth (ex:
freezing point, high specific heat, cohesion)
Life depends on hydrogen bonds in
water.
• Water is a polar molecule.
– Polar molecules have slightly charged regions.
1. Hydrogen bonds
form between slightly
positive hydrogen
atoms and slightly
negative atoms.
(oxygen)
Atom: Oxygen
Charge: Slightly
negative
_
O
H
+
H
+
Atom: Hydrogen
Charge: Slightly positive
– Nonpolar molecules do not have charged regions.
• Hydrogen bonds are responsible for important
properties of water.
– High Specific Heat: water resists changes in temp.
– Provides stability of temperature for land
masses surrounded by water & for the
temperature of the human body, & makes it an
effective cooling agent.
– Cohesion: water molecules stick to each other. We
saw this in the water lab when water built up on
the penny & rolled around on the wax paper.
– Adhesion: water molecules stick to other things.
– Ice floats on water: one of the only solids to float
on its liquid form – due to arrangement of water
molecules due to charged regions. (Density)
Freezing Point
• The freezing point is the temperature and
pressure at which a liquid material changes
from a liquid to a solid. The freezing point of a
liquid can be raised or lowered by adding
other chemicals to it, such as by adding salt to
water. Molecules slow down when forming a
solid and pack tightly. Lipids(fats) tend to have
a low freezing point.
Properties of Water (cont)
Many compounds dissolve in water.
• A solution is formed when one substance dissolves in
another. A solution is a homogeneous mixture.
– Solvents dissolve other substances. (i.e. water)
– Solutes dissolve in a solvent. (i.e. Koolaid powder)
solution
Properties of Water (cont)
– “Like dissolves like.”
– Polar solvents dissolve polar solutes.
– Nonpolar solvents dissolve nonpolar solutes.
– Polar substances and nonpolar substances
generally remain separate.
– Example: Oil (non-polar) and water (polar)
Potential Hydrogen Affects Water
pH
<7=Acid (more H+, less OH-)
7=Neutral
>7=Base (less H+, more OH-)
Maintaining homeostasis
*Buffer: Helps to maintain pH.
BIO.A.2.2
•
•
•
•
Describe and interpret relationships between structure and function at various
levels of biochemical organization (i.e., atoms, molecules, and macromolecules).
Explain how carbon is uniquely suited to form biological macromolecules.
Describe how biological macromolecules form from monomers.
Compare the structure and function of carbohydrates, lipids, proteins, and nucleic
acids in organisms.
Definitions
• Atom: The smallest unit of matter. Consists of
a nucleus surrounded by electrons.
• Molecule: The smallest unit of an element or
compound, made up of two or more atoms
held together by strong chemical bond.
• Macromolecule: A large complex molecule,
such as nucleic acids, proteins, carbohydrates,
and lipids, with relatively large molecular
weight.
Why Macromolecules?
Because….Carbon atoms have unique
bonding properties such as:
1. Carbon forms covalent bonds (strong
bonds) with up to four other atoms,
including other carbon atoms
2. They can form large, complex, diverse
molecules
Carbon atoms have unique bonding
properties – Slide 2
3. Carbon can form single, double, or triple bonds
4. Carbon forms isomers
– Isomers are compounds that have the same chemical
formula, but different structural formulas
• Example: C4H10
• Only carbon has these 4 characteristics
Many carbon-based molecules are made of many small
subunits bonded together.
• Monomers are the individual subunits.
• Polymers are made of many monomers.
• When organisms break down large organic
compounds (macromolecules), they can
obtain energy and/or put the monomers back
together to form different compounds.
Carbohydrates
CHO
ose = sugar/carb
Monomer
Polymer
Examples
Unique
monosaccharide
disaccharide (dimer), polysaccharide
Monosaccharide: glucose, fructose
Disaccharide: sucrose (table sugar)
Polysaccharide: starch & cellulose (cell wall in plants),
glycogen (in animals)
-
Provide a quick source of energy
Lipids
LIPIDS
CHONP
Monomer
Polymer
Examples
Unique
glycerol & fatty acids; polar heads & fatty acid tails
triglycerides; phospholipids
Fats, oils, cholesterol, steroids, waxes, phospholipids
- Nonpolar
- Broken down to provide energy
- Used to make steroid hormones (control stress,
estrogen, testosterone)
- Phospholipids make up all cell membranes
- Fats and oils contain fatty acids bonded to glycerol
- Phospholipids make up all cell membranes (keeps a cell
fluid like, more heat = more flexibility in fluid)
Proteins CHON
Molecule 
Monomer
Polymer
Examples
Unique
Proteins
Amino acid
Polypeptide (protein)
Enzymes (catalyze biochemical reactions), hemoglobin
(transports oxygen in blood), muscle movement, collagen
- 3D structure makes them active
- Peptide bonds hold amino acids together
- Have a side group (R) that makes each amino acid (and
therefore protein) different
- Sometimes may contain sulfur
Nucleic acids CHONP
Molecule 
Monomer
Polymer
Examples
Unique
Nucleic acids
Nucleotide (5-carbon sugar, phosphate group, & base)
Nucleic acid
DNA & RNA
- Order of the bases makes every living thing unique
- DNA stores genetic information
- RNA builds proteins
Dehydration Synthesis
• Two monomers need to join to make a
polymer. Dehydrate = lose water, Synthesis =
Build
Hydrolysis
• A polymer needs to break apart into
monomers. Water is used to do this. (the
carbs, proteins, and lipids we ingest are too
big for us to use) Hydro = use water to split
BIO.A.2.3
• Explain how enzymes regulate biochemical
reactions within a cell.
• Describe the role of an enzyme as a catalyst in
regulating a specific biochemical reaction.
• Explain how factors such as pH, temperature,
and concentration levels can affect enzyme
function.
Chemical reactions release or
absorb energy.
• Activation energy is the amount of energy that needs to
be absorbed to start a chemical reaction
A catalyst lowers activation energy.
• Catalysts are substances that speed up chemical
reactions
– Decrease activation energy
– Increase reaction rate
Enzymes allow chemical reactions to occur
under tightly controlled conditions.
• Enzymes are catalysts in living
things.
–Enzymes are needed for almost
all processes.
–Most enzymes are proteins.
–Enzymes speed up reactions
without being consumed by
increasing the reaction rate.
Disruptions in homeostasis can
prevent enzymes from functioning.
• Enzymes function best in a small range of
conditions.
– Changes in temperature or pH, or
concentration levels can affect the rate of a
reaction, also called DENATURING the
enzyme.
• An enzyme’s function depends on its
structure.
An enzyme’s structure allows only certain
reactants to bind to the enzyme.
• Substrates: reactants that bind to an enzyme
• Active site: area on the enzyme where substrates bind
Enzyme/Substrate Concentration
• Enzyme Concentration
If we keep the concentration of the substrate constant
and increase the concentration of the enzyme, the rate of
reaction increases linearly.
(That is if the concentration of enzyme is doubled, the
rate doubles.)
• Substrate Concentration
If we keep the concentration of the enzyme constant and
increase the concentration of the substrate, initially, the
rate increases with substrate concentration, but at a
certain concentration, the rate levels out and remains
constant
BIO. A.4.2
• Explain the mechanisms that permit organisms
to maintain biological balance between their
internal and external environments.
- Explain how organisms maintain homeostasis
(ex: thermoregulation, water regulation, oxygen
regulation).
Speaking of homeostasis…
• Homeostasis refers to your body maintaining
stable, constant internal conditions.
• This may include:
– Regulation of temperature (thermoregulation) Ex.:
sweating during exercise
– Regulation of pH (buffers)
– Regulation of oxygen delivery (for cellular
respiration!). Ex: heart beating faster during exercise
– - Water regulation (iso, hyper, hypo tonic)
osmoregulation - regulation of water concentrations
in the bloodstream, effectively controlling the amount
of water available for cells to absorb.)
Feedback Loops
• Feedback: Information from sensor that allows a control center to
compare current conditions to a set of ideal values.
– Feedback loop: Sensorcontrol centertargetsensor….
• Negative feedback loops: control system counteracts any change in
the body that moves conditions above or below a set point
(reversing change to return conditions to their set points)-most
functions in the body are regulated this way.
– Ex.: Thermostats, holding your breath
• Positive feedback loops: Control center uses information to increase
rate of change away from set points.
– Ex.: Cut finger increases clotting factors in blood.
1.3: Scientific Thinking &
Processes
Key concept: Science is a way of
thinking, questioning, and gathering
evidence.
BIO.B.3.3
• Apply scientific thinking, processes, tools, and
technologies in the study of the theory of
evolution.
• Distinguish between the scientific terms:
hypothesis, inference, law, theory, principle,
fact, and observation.
• Science is a process of trying to understand the
world around us using critical and logical thinking
to evaluate results and conclusions.
• Scientists gather evidence and share their
findings with one another.
• Observation: the use of our senses, computers,
and other tools to gather information about the
world.
– Ex.: Studying the interactions between gorillas by
observing their behavior.
Observations can be recorded as data
to be analyzed
• Qualitative data: Descriptions of phenomena
that can include sights, sounds, and smells.
• Quantitative data: Characteristics that can be
measured or counted such as mass, volume,
and temperature; Numbers
Scientists use observations and data to
form hypotheses
• Hypothesis: A proposed, testable answer to a
scientific question.
– Formal hypotheses are usually written in an “if,
then, because” format.
– If (change of IV) then (change of DV) because (why
you think this will happen).
How do scientists test hypotheses?
• The scientific method
– A) Observe and ask questions that lead to a problem
– B) Form a hypothesis
– C) Test the hypothesis with a controlled experiment by
making observations and gathering data.
– D) Analyze gathered data
– E) Reject (start over at step B) or Accept your
hypothesis.
– F) Form a conclusion
How do scientists test hypotheses?
• Controlled experiments study the effect of
independent variables on dependent variables.
• Independent variable: A condition that is
manipulated, or changed, by a scientist. Effects
are measured by changes in dependent variables.
• Dependent variable: observed and measured
during an experiment.
– Example: Testing medication to treat blood pressure.
IV: medication dose, DV: blood pressure.
Controlled experiments
• Only one independent variable should be
changed in an experiment.
• Other conditions must stay the same and are
called constants.
• Controlled experiments must have a control
group – everything is the same as the
experimental groups but the independent
variable is not manipulated.
– Example: When testing blood pressure medication,
control group receives none of the active ingredient.
• A large number of test subjects or trials is ideal.
Other important science terms
• Inference: A conclusion reached on the basis of evidence and
reasoning. (Ex: you make an inference when you use clues to figure
something out).
• Law: A law that generalizes a body of observations. At the time it is
made, no exceptions have been found to a law. It explains things but
does not describe them; serves as the basis of scientific principles.
(Ex: Law of Gravity, Newton’s Laws of motion).
• Theory: A proposed explanation for observations and experimental
results that is supported by a wide range of evidence – may
eventually be accepted by the scientific community. (Ex: Big Bang
Theory, Evolution & Natural Selection)
• Principle: A concept based on scientific laws and axioms (rules
assumed to be present, true, and valid) where general agreement is
present. (Ex: Buoyancy Principle)
• Fact: An observation that has been repeatedly confirmed.