Science 10 A.P. study guide HTA

advertisement
SCIENCE 10 A.P. STUDY GUIDE
2011
Holy Trinity Academy
1
Unit ONE: Chemistry
1. Describe the basic particles that make up the underlying structure of matter, and investigate related
technologies
a.identify historical examples of how humans worked with chemical substances to meet their basic needs
b. outline the role of evidence in the development of the atomic model consisting of protons and neutrons
(nucleons) and electrons; i.e., Dalton, Thomson, Rutherford, Bohr
c. identify examples of chemistry-based careers in the community
2. Explain, using the periodic table, how elements combine to form compounds, and follow IUPAC guidelines for
naming ionic compounds and simple molecular compounds
a. illustrate an awareness of WHMIS guidelines, and demonstrate safe practices in the handling, storage and
disposal of chemicals in the laboratory and at home
b. explain the importance of and need for the IUPAC system of naming compounds, in terms of the work that
scientists do and the need to communicate clearly and precisely
c. explain, using the periodic table, how and why elements combine to form compounds in specific ratios
d. predict formulas and write names for ionic and molecular compounds and common acids, using a periodic table,
a table of ions and IUPAC rules
e. classify ionic and molecular compounds, acids and bases on the basis of their properties; i.e., conductivity, pH,
solubility, state
f. predict whether an ionic compound is relatively soluble in water, using a solubility chart
g. relate the molecular structure of simple substances to their properties
h. outline the issues related to personal and societal use of potentially toxic or hazardous compounds
3. Identify and classify chemical changes, and write word and balanced chemical equations for significant
chemical reactions, as applications of Lavoisier’s law of conservation of mass
a. provide examples of household, commercial and industrial processes that use chemical reactions to produce
useful substances and energy
b. identify chemical reactions that are significant in societies
c. describe the evidence for chemical changes; i.e., energy change, formation of a gas or precipitate, colour or
odour change, change in temperature
d. differentiate between endothermic and exothermic chemical reactions
2
e. classify and identify categories of chemical reactions; i.e., formation (synthesis), decomposition, hydrocarbon
combustion, single replacement, double replacement
f. translate word equations to balanced chemical equations and vice versa for chemical reactions that occur in
living and nonliving systems
g. predict the products of formation (synthesis) and decomposition, single and double replacement, and
hydrocarbon combustion chemical reactions, when given the reactants
h. define the mole as the amount of an element containing 6.02 × 1023 atoms (Avogadro’s number) and apply the
concept to calculate quantities of substances made of other chemical species
i. interpret balanced chemical equations in terms of moles of chemical species, and relate the mole concept to the
law of conservation of mass
Introduction and Review
Chemistry: The study of matter, its properties, composition, and behaviors
WHMIS: Workplace Hazardous Materials Information System
A set of eight symbols to quickly identify the potential hazard a substance presents.
MSDS: Material Safety Data Sheets
Are information sheets about specific chemicals. They describe the types of hazards, handling and clean up
procedures, toxicity reports, manufacturing information.
IUPAC: International Union of Pure and Applied Chemistry
In order to achieve understanding scientists must communicate with each other and with the rest of the world.
They must be able to communicate clearly and precisely using generalizations, theories, and scientific laws. When
they communicate it should be international (meaning and symbols), precise, and as simple as possible (easily
understood). The symbols and numbers on the periodic table are internationally accepted.
Periodic table: a reference table that contains information on all the natural and manmade elements
Empirical knowledge: knowledge obtained by our physical senses; something measureable
Theoretical knowledge: comes from attempts to explain empirical knowledge
Safe handling:
Read, listen to, and follow all instructions carefully
Wash your hands after each activity that uses chemicals
Wear appropriate safety equipment, goggles and aprons, when handling hazardous chemicals
Smell a substance by fanning the smell toward you with your hand. Do not put your nose over the substance
3
Do not taste anything
Never pour liquids into containers in your hand
Never use damaged glassware
Clean up any spills immediately
Never look into test tubes or containers from the top. Look through the sides
Safe Storage:
Label any container you put a chemical in
Never store a chemical in damaged containers
Oil based paints, gas, solvents, oil, herbicides should be stored in the garage
Household cleaning supplies and plant fertilizers should be stored on a shelf out of reach of children
Safe disposal:
Follow instructions as to disposal of all chemicals
Ask if you are unsure is a waste should be poured in the sink
Unused prescription drugs should be returned to the pharmacist for proper disposal
Oil and oil filters should be stored out of the house and used samples should be recycled and collected at a
transfer site
Paints, spray cans, pressurized containers go to the transfer station (toxic round up)
Classification of Matter
Matter: anything that has mass and occupies space. May be solid, liquid, or gas
Mass: the quantity of matter present in a body. The mass of a body is constant and independent of its location.
Pure substance: substances that donot breakdown into new elements or compounds. Their particles all have the
same physical and chemical properties. They have a definite composition. Pure water, pure ethanol, pure oxygen,
pure gold
Compound: Two or more elements chemically bonded together. They can be separated chemically into simpler
substances Ex. Water, ethanol, table sugar
Element: Cannot be broken down into new elements/simpler substances. Each element is composed of only one
type of atom. Ex. Oxygen, carbon, sodium, gold
Homogeneous mixture: a mixture that has uniform composition. It looks like only one substance. The different
components are not visible
4
Heterogeneous mixture: a mixture that does not have uniform composition (it has 2 or more parts to it, that can
be seen). The different components are visible
Alloy: a homogeneous mixture of two or more metals. Usually a solid
Solution: a homogeneous mixture of substances that dissolve or mix evenly with each other. Usually a liquid
Solute: the substance (usually a solid) that dissolves in a solvent forming a solution
Solvent: the liquid that dissolves the solid in a solution
Physical properties: those characteristics that can cause a physical change in a substance. They can be identified
without reference to another substance. Ex. Boiling point, color, density, ductility, conductivity, magnetism,
malleability, melting point, phase
Physical change: this occurs when the matter changes but no new substances are produced. Ex. Phase changes:
freezing/melting, boiling, condensing, sublimation
Chemical properties: the chemical reactions that a substance can undergo
Chemical change: this occurs when matter is changed to produce a new substance. The chemical and physical
properties of the new substance will be different from the original substance. Ex. Burning is adding oxygen to a
substance forming new gases. Evidence includes: gases, light, heat produced, color change, precipitate forms.
Chemistry based careers in the community: Chemical Engineer, Cosmetology, Dietary nutritionist, pharmacist,
food processing, and forensic police officer
Historical examples of the use of chemical substances




Clay used to make pots to hold water, bricks to build structures
Sulfur: Latin for “burning stone”, historically called brimstone. Was used as an insecticide and for
pyrotechnics in ancient Greece and Rome
Iron used to make weapons in 1500 BC (Hittites)
Copper first isolated about 9000 years ago, used for hammers, axes, containers
Atomic Theories
Dalton model




Billiard ball model
The atom was the smallest particle of matter
It had no charges
It was a solid sphere
Thompson model



The raisin bun model
The atom was a solid sphere
It had positive and negative charges on it
5

It was the smallest part of matter
Rutherford Model



The planetary model
The atom was composed of a postive nucleus and separate negative electrons
The electrons where orbiting the nucleus
Bohr Model




Electron energy level model
Electrons occupy specific energy levels around the nucleus
The first energy level holds only 2 electrons, the second 8, third 8, fourth 18, fifth 18
From this we draw energy level diagrams for the atomic structure of the first 20 elements
Quantum Mechanics Model


Electron cloud model
Electrons travel between energy levels therefore there is only a “probability” of finding an electron in a
given orbit at a given time.
Atomic structure
Nucleus:






Central core of the atom
Has all the mass
Occupies very little volume
Atoms are mostly empty space
Composed of protons and neutrons
Different atoms have different numbers of protons
Protons




Are part of the nucleus
Have a positive charge
Different elements are composed of atoms that have different numbers of protons
The atomic number of an element equals the number of protons in the atoms of that element
Neutrons




Are part of the nucleus
Have no charge
Atoms with the same number of protons but different numbers of neutrons are called isotopes of that
element
The atomic mass is the sum of the mass of the neutrons and protons in the nucleus
Nuclear Energy



The protons and neutrons are held together by strong forces.
The protons and neutrons are composed of smaller particles.
Einstein discovered that the matter in the nucleus can change into energy
6


E=mc2 tells us how much energy matter can produce
Nuclear reactions (fission and fusion) release tremendous amounts of energy
Electrons





Are found outside the nucleus, they orbit the nucleus
They have a negative charge
They are found in storage shelves called energy levels or orbitals
For neutral atoms the number of protons equals the number of electrons which also equals the atomic
number
Atoms that gain or lose electrons are called ions
Isotopes





Atoms of the same element that have different numbers of neutrons
There atomic masses are different
They have the same number of protons therefore they are still the same element
Ex. Carbon 14 has 6 protons, 8 neutrons
Carbon 12 has 6 protons, 6 neutrons

All metal atoms will lose electrons in chemical reactions to form positive ions, called cations. They will
have more protons than electrons therefore have a positive charge
All nonmetal atoms will gain electrons in chemical reactions to form negative ions, called anions.
Ions

Ionic compounds






Made from metal and nonmetal
Or metal and polyatomic ion
Or two polyatomic ions
Or polyatomic ion and nonmetal
Must balance ions charges between species involved. They transfer electrons forming ionic bonds
Use brackets around polyatomic ions
Molecular compounds



Made from two or more nonmetals
Most formulas are memorized
donot balance charges, they share electrons forming covalent bonds
Acid compounds





Are all formed from hydrogen compounds, are not molecular, neither ionic, but will form conducting
solutions
Most are memorized formulas and names
Most are on the back of the periodic table
Turn blue litmus paper red
Have a pH of less than 7
Bases
7
 Most are compound with hydroxides
 Are all ionic compounds and will form conductive solutions
 Turn red litmus paper blue
 Have pH of greater than 7
Chemical formulas
Should always communicate three things:



1: the kind of atoms present using accepted symbols
2: the simplest ratio of atoms or ions given by the formula subscript
3: the physical state of the substance at STP, given by s, l, g, or aq.
Chemical reaction and equations








Illustrate the conservation of mass
Mass of reactants must equal the mass of the products
This is reflected in a balanced chemical equation
Chemical equations are a simple, precise, and an international method of communicating information
about a chemical reaction
Reactants on left side, products on right side
Both are separated by an arrow pointing to the reactants/left, not an equals sign
Write correct formulas first, write states of matter next (s, l, g, or aq)
Finally balance the equation without changing the chemical formulas
Balancing equations





Begin with the atom that has the biggest number (subscript)
Determine the lowest common multiple between the reactant and the product
Write this number as the coefficient for both these two elements/compounds
Balance the remaining atoms using the same strategy
The number of atoms of each element must be the same on both side of the equation.
Reaction Types:





Formation= E + E  C
Decomposition = C  E + E
Single Replacement = E + C  E + C
Double Replacement = C + C  C + C
Combustion = HC + Oxygen  CO2 + H2O
Evidence for Chemical reactions





Color change
Temperature change
– Endothermic-feels cold
– Exothermic-feels hot-may produce flames
Gas produced (bubbles or fizzes)
Light produced
Precipitate forms-solution often goes cloudy
Moles


A quantity of items similar to a pair (2), dozen (12), gross (144), ream (500)
One mole is 6.02 x 10 to the power 23 items
8

It is used only to measure amounts of atoms and molecules
Molar Mass







Is the mass of one mole of element or a compound
Ex. Carbon is 12.01 grams per mole
Molar mass for every element is on the periodic table
Molar mass of compounds is determined by adding the sums of the molar masses of all the atoms in that
compound
We can convert from mass to moles or the reverse with a simple equation
Mass = moles x molar mass m = n x M
Moles = mass divided by molar mass n = m/M
Endothermic reactions




Energy is used by the reaction
Products have more energy than the reactants
The reaction temperature decreases
The reaction “feels” cold
Exothermic reactions




Energy is given off by the reaction
Less energy in the products than the reactants
The reaction temperature increases
The reaction “feels” warm or hot
9
Unit TWO: Physics
1. Analyze and illustrate how technologies based on thermodynamic principles were developed before the laws
of thermodynamics were formulated
a. illustrate, by use of examples from natural and technological systems, that energy exists in a variety of forms
b. describe, qualitatively, current and past technologies used to transform energy from one form to another, and
that energy transfer technologies produce measurable changes in motion, shape or temperature
c. identify the processes of trial and error that led to the invention of the engine, and relate the principles of
thermodynamics to the development of more efficient engine designs
d. analyze and illustrate how the concept of energy developed from observation of heat and mechanical devices
2. Explain and apply concepts used in theoretical and practical measures of energy in mechanical systems
a. describe evidence for the presence of energy; i.e., observable physical and chemical changes, and changes in
motion, shape or temperature
b. define kinetic energy as energy due to motion, and define potential energy as energy due to relative position or
condition
c. describe chemical energy as a form of potential energy
d. define, compare and contrast scalar and vector quantities
e. describe displacement and velocity quantitatively
f. define acceleration, quantitatively, as a change in velocity during a time interval:
g. explain that, in the absence of resistive forces, motion at constant speed requires no energy input
h. recall, from previous studies, the operational definition for force as a push or a pull, and for work as energy
expended when the speed of an object is increased, or when an object is moved against the influence of an
opposing force
i. define gravitational potential energy as the work against gravity
j. relate gravitational potential energy to work done using Ep = mgh and W = Fd and show that a change in energy
is equal to work done on a system
k. quantify kinetic energy using Ek = 1/2 mv2 and relate this concept to energy conservation in transformations
(e.g., for an object falling a distance “h” from rest: mgh = Fd = 1/2 mv2)
l. derive the SI unit of energy and work, the joule, from fundamental units
10
m. investigate and analyze one-dimensional scalar motion and work done on an object or system, using algebraic
and graphical techniques
3. Apply the principles of energy conservation and thermodynamics to investigate, describe and predict
efficiency of energy transformation in technological systems
a. describe, qualitatively and in terms of thermodynamic laws, the energy transformations occurring in devices and
systems
b. describe how the first and second laws of thermodynamics have changed our understanding of energy
conversions
c. define, operationally, “useful” energy from a technological perspective, and analyze the stages of “useful”
energy transformations in technological systems
d. recognize that there are limits to the amount of “useful” energy that can be derived from the conversion of
potential energy to other forms in a technological device
e. explain, quantitatively, efficiency as a measure of the “useful” work compared to the total energy put into an
energy conversion process or device
f. apply concepts related to efficiency of thermal energy conversion to analyze the design of a thermal device
g. compare the energy content of fuels used in thermal power plants in Alberta, in terms of costs, benefits,
efficiency and sustainability
h. explain the need for efficient energy conversions to protect our environment and to make judicious use of
natural resources
Energy





the capacity to do work
It can cause changes in motion, shape, temperature, light
It can cause physical or chemical changes
Forms include: chemical, nuclear, geothermal, wind, solar, tidal, gravitational, kinetic, thermal, electrical,
mechanical
All forms of energy can be traced back to the sun. The original form of almost all energy on the earth is
the sun.
Forms of Energy




Geothermal- heat in the earth produced by the radioactive breakdown of matter
Tidal-movements of the ocean produced by gravitational attraction of the moon
Solar-light from fusion reaction in the sun
Wind-produced by differential light absorption and heating of the earth’s surface
Energy conversion Technologies


Windmills
Hydroelectric dams
11






Gas/goal power stations
Gas engine
Steam engine
Electric motor
Solar cells
Hydrogen fuel cell
Energy Conversions





Several things can happen as a result of energy converting from one form to another
Change in motion
Change in shape
Change in temperature
Change in light
Engines



An engine is a man made device that used combustion to convert one form of energy into another for a
specific purpose (motion)
The first engine was a steam engine. It used steam (thermal energy) to create mechanical energy
(motion)
Modern engines use hydrocarbons (gasoline or diesel or propane)—chemical energy to create mechanical
energy (motion)
Improvements in engines


It required a better understanding of energy and the laws of thermodynamics to make better engines
Any energy conversion produces waste heat. This will cause expansion of metal and excess friction,
damaging parts. So ways of eliminating waste heat had to be incorporated into engine design (radiators,
cooling systems, lubrication) this allowed engines to get bigger, run longer and produce more power
Energy and the laws of thermodynamics




The concept of energy developed from observations of heat and mechanical devices
This lead to the laws of thermodynamics
First law: Energy is always conserved; or energy in = energy out. You cannot get more than what you put
in.
Second law: No conversion is ever 100 % efficient. During any conversion there will always be waste heat
produced. (You can never have a perpetual motion machine)
Motion as a description of energy




Energy involves the capacity to do work
Work involves movement/motion
Changes in motion are determined by changes in distance and time
Changes in distance and time are measured as speed or velocity
Speed


The distance travelled by an object during a given time interval divided by the time interval.
It is a scalar quantity; there is no direction described
Distance time graphs
12






Describe motion of an object
Distance is on the vertical (y) axis
Time is on the horizontal (x) axis
Straight line means uniform motion
Slope of the line determines the magnitude of the speed
Curved lines describe nonuniform motion: acceleration or deceleration
Measurement in science
Answers cannot be more precise than the least precise number used in the calculation
Accuracy: how close you are to the target, the correct measurement, free from error
Precision: how careful you were in making the measurement
Significant digits
Are those digits obtained from a properly taken measurement
1.
2.
3.
Count all digits from 1 to 9 plus zeros in between and following another digits
Do not count zeros in front of a value because they are only there to set the decimal place (they only
tell us where the measurement started)
Exact numbers are not uncertain and are said to have an infinite number of significant digits. Ex.
Numbers that are defined/constants, and numbers that result from counting objects.
Multiplication and division.
When multiplying or dividing, multiply or divide, then round off the answer to the least number of significant digits
of the numbers used in the calculation.
Scientific notation
Is a method of expressing values as a number between 1 and 10 multiplied by a power of 10.
Do not use scientific notation unless required:
1.
2.
For expressing the proper number of significant digits
For making the value less cumbersome in written work or calculations.
Scalar quantities: describe magnitude but not direction. Ex. Distance is a scalar quantity that describes the length
of a path between two points or locations. Ex. Distance, time, speed
Vector quantities: describe magnitude with direction. To distinguish these quantities symbols for vectors are
written with arrows above them while symbols for scalars are not. Ex. Position, velocity, acceleration,
displacement
Displacement is a vector quantity that describes the straight line distance from one point to another as well as the
direction. It is mathematically defined as the difference between two positions
Position is a vector quantity that describes a specific point relative to a reference point
13
Velocity


The displacement of an object during a time interval divided by the time interval.
Displacement (and velocity) is a vector quantity. They describe an amount and a direction. Displacement
describes the straight line distance from one point to another (not necessarily the total distance) as well
as the direction. To Calculate displacement you need to know the beginning and final positions.
Acceleration





Not all objects move with uniform motion, constant speed or velocity
Objects can slow down, speed up, stop or start moving
The rate at which an objects motion changes is called acceleration
Acceleration is the rate of change in velocity
When objects slow down this is negative acceleration or deceleration
Force










A push or pull on an object
The amount of force is affected by the size, or amount of the object (mass) and by the rate of movement
of the object (acceleration)
F = force (Newtons)
m=mass (kilograms)
a=acceleration (m/s2)
F=mxa
The units for force are called Newtons, named after the classical physicist Isaac Newton
1 Newton is the force required to move a 1 kilogram mass at 1m/s2, ignoring friction.
Inertia is the property of an object to resist motion, or to stay in motion
In the absence of resistive forces, motion at a constant speed requires no energy input
Work








The transfer of energy from one object to another
The application of a force over a distance
The object must move in order for work to be done
W=work (joules)
F=force (Newtons)
d=distance (meters)
W=Fxd
Graphically, work is the total area below the line in a force vs distance graph
Gravitational potential energy








The stored energy in an object due to its distance above the surface of the Earth; work against gravity
It takes more energy (work) to move an object higher above a surface. Thus the higher an object the more
energy it will have and the more work it can do when it falls and collides with something on the way down
Ep = gravitational potential energy
m=mass (kilograms)
g=accelerations due to gravity (9.81 m/s2)
d=distance (m)
Ep = m x g x d
Work can be converted to potential energy and vice versa
14


W = F x d (substitute m x a for force)
W = m x a x d = Ep
Kinetic energy






The energy of motion
Is a function of the mass and velocity (speed) of the object
Ek = ½ mv2
Ek= kinetic energy (Joules)
m= mass (kilograms)
v= velocity or speed (m/s)
Mechanical energy



The energy due to the motion and position of an object
Em = Eg + Ek
Energy is always conserved in any system therefore in any system potential energy of whatever form gets
converted to kinetic energy (and other forms) and vice versa so the total energy always remains the same
Laws of thermodynamics


First Law: Also called the law of conservation of energy. Energy cannot be created or destroyed, but can
be transformed from one form to another or transferred from one object to another. These
transformations are called energy conversions/systems.
Second Law: No process is ever 100% efficient. There will always be waste or unintended forms of energy
released from any energy conversion, system, or process. Heat always flows from a hot object to a cold
object. Perpetual motion machines can not exist
Efficiency

Efficiency = useful work output
total work input
x 100
useful work is the intended purpose of the device or activity
nonuseful work is the unintended output from the device or activity.
Efficiencies of modern devices








Incandescent light bulb—5%
Fluorescent light bulb– 20 %
Gas engine—20%
Electric motor– 50-90%
Coal burning power plant
Natural gas burning power plant
Hydroelectric dam—90%
Photovoltaic cells (solar panels)
Need for efficiency


Make judicious and prudent use of our natural resources
Protect the environment: exploration and extraction damages, pollutants from combustion or
manufacturing of materials for energy production
15
Unit THREE: Biology
1. Explain the relationship between developments in imaging technology and the current understanding of the
cell
1.
2.
3.
4.
5.
6.
7.
8.
describe how advancements in knowledge of cell structure and function have been enhanced and are
increasing as a direct result of developments in microscope technology and staining techniques
explain three advantages of using light microscopes
outline the advantages of using electron microscopes
List the properties of a light microscope and how to use the microscope
Describe how to make a wet-mount slide and make drawings from the microscope
identify areas of cell research at the molecular level
state that a virus is a non-cellular structure consisting of DNA or RNA surrounded by a protein coat
trace the development of the cell theory: all living things are made up of one or more cells and the materials
produced by these, cells are functional units of life, and all cells come from pre-existing cells
As the microscope has developed and improved so has our knowledge and understanding of the cell and its
components. Better technologies have allow science to identify, describe, and explain cell organelles and the
processes they control, such as cell division, respiration, photosynthesis, and transport mechanisms.
Anton Van Leeuwenhoek: one of the first to build simple microscope and observe nature and draw what he saw.
Robert Hooke: 1665, was the first to use the word “cell” to describe what he saw with microscopes of the time.
Simple microscope: uses one lens placed in front of the object to magnify the light reflected from the object
Compound microscope: uses at least two lenses (eyepiece and objective) to magnify the image.
Light microscope: uses lenses to magnify the light reflected off an object
Electron microscope: uses electrons to create an image seen on a monitor
Scanning e.m.: bounces electrons off the surface (usually coated with a thin film of gold) of an object, creates a 3d image of the exterior of the object. Can only examine outside surface of objects, but with very high resolution
and magnification.
Transmission e.m.: sends electrons through the tissues/cells of a specimen, the scattering of the electrons is
recorded by sensors and these create an image of the specimen. It views internal structure of cells with very high
magnification and resolution.
Binocular: two eyepieces (oculars)
Advantages of light microscopes: Inexpensive, Can view live specimens, Simple specimen preparation
Disadvantages of light microscopes: Can only magnify up to 4000x, Resolution decreases with increasing
magnification
16
Advantages of electron microscopes: very high magnification, very high resolution
Disadvantages of electron microscopes: expensive, require extensive training, only view dead tissue
Properties of light microscopes
a.
b.
c.
d.
Magnification: The light from an object is magnified as it goes through two primary lenses, the objective
lens first, then the ocular lens, then it enters your eye. Our microscope have one ocular that magnifies 10
x and three different objective lenses that magnify 4x, 10x, and 40 x.
Resolution: This is the sharpness or clarity of the image you see. As the magnification increase the
resolution decreases. As the magnification increases you are looking at a smaller and smaller part of the
object and the microscope gathers less and less light, thus the image appears fuzzier and darker (so you
must turn up the light when using high magnifications)
inversion: When light goes through a lens the image is flipped upside-down and backwards. This is called
inversion. Objects seen through the light microscope are inverted. Top is bottom and left is right.
field of view: This is the circular area you see when you look through the ocular. As magnification
increases the diameter of the field of view decreases. As magnification increases you look at a smaller
and smaller area of the object.
Wet mount slide preparation



1. obtain small thin section of specimen and place on a clean slide
2. place a drop of water on the specimen
3. place a cover slip over the specimen starting at a 45 angle
Staining slides


1. place one or two drops of stain on one edge of the cover slip, so the drop falls on the cover slip and the
glass slide.
2. take a piece of paper towel and place it against the opposite edge of the cover slip. Allow the paper
towel to absorb the water from under the cover slip
Linear magnification of picture or drawing





Pick on object in your field of view
Estimate how many times that object will fit across the field of view
Divide the field of view diameter by that number to approximate the size of the object, this is the actual
size of the object
Use a ruler to measure the same object in your drawing, this is the drawing size
Drawing = Drawing size
Mag
Actual size
Virus structure




Are noncellular
They are protein coat with genetic material inside
Have no cell organelles (parts)
They can only reproduce inside another living cell
Cell theory
17
 Developed by Schleiden, Schwann, and Virchow (mid 1800’s)
 1. All organisms are composed of one or more cells
 2. The cell is the smallest functional unit of life
 3. All cells are produced from other cells
2. Describe the function of cell organelles and structures in a cell, in terms of life processes, and use models to
explain these processes and their applications
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
describe the cell as a functioning open system that acquires nutrients, excretes waste, and exchanges matter
and energy
(A.P. Cells communicate by generating, transmitting, and receiving chemical signals)
(A.P. Cells communicate with each other through direct contact with other cells or from a distance via
chemical signaling)
identify the structure and describe, in general terms, the function of the cell membrane, nucleus, lysosome,
vacuole, mitochondrion, endoplasmic reticulum, Golgi apparatus, ribosomes, chloroplast and cell wall, where
present, of plant and animal cells
(A.P. DNA, and in some cases RNA, is the primary source of heritable information)
(A.P. eukaryotic cells maintain internal membranes that partition the cell into specialized regions)
(A.P. Archea and bacteria generally lack internal membranes and organelles and have a cell wall)
compare the structure, chemical composition and function of plant and animal cells, and describe the
complementary nature of the structure and function of plant and animal cells
describe the role of the cell membrane in maintaining equilibrium while exchanging matter; identify functions
of membrane proteins; fluid mosaic model, membrane proteins, other important membrane compounds
describe how knowledge about semi-permeable membranes, diffusion and osmosis is applied in various
contexts
describe cell size and shape as they relate to surface area to volume ratio, and explain how that ratio limits cell
size
compare passive transport of matter by diffusion and osmosis with active transport in terms of the particle
model of matter, concentration gradients, equilibrium and protein carrier molecules, protein pumps
(A.P. Cell membranes separate the internal environment of the cell from the external environment)
(A.P. Selective permeability is a direct consequence of the membrane structure, as describe by the fluid
mosaic model)
use models to explain and visualize complex processes like diffusion and osmosis, facilitated diffusion, endoand exocytosis, and the role of cell membrane in these processes
(A.P. Viral replication results in genetic variation, and viral infection can introduce genetic variation into hosts)
Cells:





A functioning open system that acquires nutrients, excretes wastes, and exchanges matter and energy
They communicate by cell to cell contact (immune cells)
They communicate over distances using chemicals (neurotransmitters and hormones)
Used for single celled or multicelled organisms
In single celled organisms, signal transduction pathways influence how the cell responds to its
environment. Some microbes use chemicals to communicate with other nearby cells and to regulate
specific pathways in response to population density (quorum sensing)
Cell Organelles





Nucleus
Chromosomes
DNA
RNA
Plasmids
18











Centriole
Mitochondria, cristae and matrix
Chloroplast, grana, thylakoids, stroma, chlorophyll a
Vacuole
Golgi apparatus, cisternae
Endoplasmic reticulum, rough and smooth
Ribosome, ribosomal RNA and protein
Lysosome, apoptosis
Microtubules
Flagella
Cilia
Plant vs Animal cells
Plant cells: cell wall(cellulose), chloroplast, large vacuoles
Animal cells, no cell wall, centrioles, small vacuoles
Prokaryotic vs Eukaryotic
Archaea and Bacteri generally lack internal membranes (membrane bound organelles) and have a cell wall
Noneukaryotic organisms have circular chromosomes, while eukaryotic organisms have multiple linear
chromosomes, some exceptions exist
Prokaryotes, viruses and eukaryotes can contain plasmids
Cell membranes: Fluid Mosaic Model















The cell membrane can “pinch off” or be added to (forming vacuoles) giving it a
dynamic/changing/fluid/flexible nature
Mosaic comes from the proteins scattered throughout the membrane
Phospholipid bilayer
Phosphates on the outside, both sides, hydrophilic
Lipid tails “sandwiched” on the inside, hydrophobic
Integral proteins span the membrane, used as channels and for transport in and out. These make the
membrane semipermeable; the membrane selects, by size, what particles can pass in and out.
Peripheral proteins, usually embedded on the outside, used as identity markers and receptors
Cholesterol, provides flexibility to membrane
Carbohydrates, used as identity markers
Glycoprotiens
Glycolipids
Membrane proteins also, Transport material in and out of the cell, Receive chemical signals, Recognition
of other cells, perform Enzyme activity
Phospholipids give the membrane both hydrophilic and hydrophobic properties. The hydrophilic
phosphate portions of the phospholipids are oriented toward the aqueous external or internal
environments, while the hydrophobic fatty acid portions face each other within the interior of the
membrane itself.
Embedded proteins can be hydrophilic, with charged and polar side groups, or hydrophobic, with
nonpolar side groups.
Small, uncharged polar molecules and small nonpolar molecules, such as N2, freely pass across the
membrane. Hydrophilic substances such as large polar molecules and ions move across the membrane
19

through embedded channel and transport proteins. Water moves across membranes and through channel
proteins called aquaporins.
Cell walls provide a structural boundary, as well as a permeability barrier for some substances to the
internal environments.
Cell membrane transport mechanisms
Passive transport: includes diffusion, osmosis, and factilitated diffusion. This is the primary way cell resources are
imported and cell wastes are exported. No energy is required
Nonpassive transport: include active transport, endocytosis, and exocytosis. These all require energy
Diffusion






The movement of particles from an area of high concentration to an area of low concentration
Particles flow down the concentration gradient
Does not require cellular energy
Can occur across semipermeable membranes
Osmosis is a special name for the diffusion of water
Factors that affect the rate of diffusion
 Temperature - the faster the temp. the faster the diffusion
 Size of particles - larger particles will not diffuse due to the semipermeable nature of the
membrane
 Concentration gradient - the larger the gradient the faster the rate of diffusion
Concentration descriptors





Isotonic – the concentrations are equal
Hypertonic – the concentration is high, meaning the particle concentration is high compared to another
solution
Hypotonic – the concentration is low, meaning the particle concentration is low compared to another
solution
Particles always flow from high to low conc. By diffusion (from hyper to hypo)
Water will flow from low to high particle conc. (from hypo to hyper) which still is from high to low water
concentration
Facilitated Diffusion


Uses membrane proteins to move substances into or out of the cell, usually charged and polar molecules
through a membrane.
Does not use cellular energy
Active Transport



The movement of substances from an area of low conc. into an area of high conc.
Uses transport proteins in the cell membrane
Uses cellular energy
Endocytosis



There are two forms
Phagocytosis or cell eating. The cell engulfs larger molecules into a vacuole.
Pinocytosis or cell drinking. The cell engulf small molecules into a vesicle
20
Exocytosis

The cell produces a waste, or a product produced by the cell, in a vacuole or vesicle and moves it out of
the cell.
Cell metabolism













Viruses:
Cells range in size from 1 um to 1 mm
Most cells are very small
The size of cells is limited by metabolism
Metabolism refers to the chemical reactions and processes that go on in the cell to keep the cell alive
In order for metabolism to be maintained nutrient must pass through the cell membrane to be used
inside the cell.
Cells can be affected by biotic and abiotic factors (temp, conc., light)
The greater the volume of the cell the greater the metabolism needed to keep it alive.
As cell size increases the volume increases faster than the surface area of the cell membrane.
This creates a problem for larger cells. There comes a point when the surface area of a cell cannot supply
nutrients fast enough for the demands of the volume of the cell.
At this point the cell cannot grow any bigger
Very large cells (fat cells) are just storage cells and have very slow metabolism.
This surface area to volume relationship is what limits the size of cells
Therefore cells cannot grow to be very big; they do not grow bigger than 1 mm.
a. Viral replication differs from other reproductive strategies and generates genetic variation via various
mechanisms.
1. Viruses have highly efficient replicative capabilities that allow for rapid evolution and acquisition of new
phenotypes.
2. Viruses replicate via a component assembly model allowing one virus to produce many progeny simultaneously
via the lytic cycle.
3. Virus replication allows for mutations to occur through usual host pathways.
4. RNA viruses lack replication error-checking mechanisms, and thus have higher rates of mutation.
5. Related viruses can combine/recombine information if they infect the same host cell.
6. HIV is a well-studied system where the rapid evolution of a virus within the host contributes to the pathogenicity
of viral infection.
b. The reproductive cycles of viruses facilitate transfer of genetic information.
1. Viruses transmit DNA or RNA when they infect a host cell.
• Transduction in bacteria
• Transposons present in incoming DNA
2. Some viruses are able to integrate into the host DNA and establish a latent (lysogenic) infection. These latent
viral genomes can result in new properties for the host such as increased pathogenicity in bacteria.
3. Analyze plants as an example of a multicellular organism with specialized structures at the cellular, tissue and
system levels
1.
2.
explain why, when a single-celled organism or colony of single-celled organisms reaches a certain size, it
requires a multicellular level of organization, and relate this to the specialization of cells, tissues and systems
in plants
explain and investigate the transport system in plants; i.e., xylem and phloem tissues and the processes of
transpiration, including the cohesion and adhesion properties of water, turgor pressure and osmosis;
21
3.
4.
5.
6.
diffusion, active transport and root pressure in root hairs, translocation of sugars and amino acids from source
and sink.
describe how the cells of the leaf system have a variety of specialized structures and functions; i.e., epidermis
including guard cells, palisade tissue cells, spongy tissue cells, and phloem and xylem vascular tissue cells to
support the process of photosynthesis
explain and investigate the gas exchange system in plants; i.e. guard cells, stomata and the process of
diffusion
explain and investigate phototropism and gravitropism as examples of control systems in plants, trace the
development of theories of phototropism and gravitropism
(A.P. Signal transmission within and between cells mediates gene expression; ex. Seed germination and
gibberellin)
multicelluarity and cell specialization in plants
single cells must



Must carry out all functions necessary for life
Ex. Breathing, excretion, food intake, communication, reproduction
Ex. Paramecium, euglena, bacteria
Specialization








Cells in multicelled organisms are specialized to perform certain functions by expressing some of their
genes but not others. Consequently many of these cells lose some of the other processes that single
celled organisms can do.
Ex. Muscle cells contract, have many mitochondria, but cannot divide.
Ex. Red blood cells transport gases but have no nucleus
There are over 200 different cells types in humans
Multicelled organisms show emergent properties
These properties arise from the interaction of component parts. The whole is greater than the sum of the
parts
No one part/tissue/cell can produce this property but working together with other cells/tissues/organs
this property emerges.
Ex. Consciousness/self awareness is a property of the human brain produced by the interaction of nerve
cells in the organ called the brain.
Ex. Circulation of blood is a property of the heart and blood vessels
Plant tissues/ parts








Leaf: location for photosynthesis
Stem: supports leaves off the ground, connects leaves to roots
Roots: anchor the plant, obtain water and nutrients for leaves
Vascular tissue: cells that transports nutrients and water inside the plant, between roots and leaves.
Xylem hollow dead cells that transport water and minerals, phloem living cells that transport sugars.
Meristematic tissue (meristem)—is the growth tissue in a plant
Apical meristems-growth from the ends of stems (terminal buds and axillary buds). Causes elongation of
roots or stems
Lateral meristems- growth inside the stem or root that causes it to get wider.
Roots stems and leaves can be modified to perform other functions
 Leaves: Bulbs for food storage and tendrils for climbing
 Stem: tubers for food storage and tendrils for climbing
22

Roots: food storage
Leaf parts:
Cuticle
Epidermis
Palisade layer
Spongy layer(mesophyll)
Guard cells
Stomata
Veins/vascular tissue
water transport in plants (cohesion tension theory)






Water evaporates from the leaves through stomata, called transpiration
Leaf cells replace water by osmosis from xylem
Causes a pull of water to the leaf (water cohesion)
Water travels (transpiration pull) through the dead, hollow, xylem cells
Cohesion and adhesion are due to hydrogen bonding (polarity) of water molecules
Flow of water is a continuous stream (transpiration stream) due to cohesion of water to itself and
adhesion to the xylem cell walls
Transpiration: the loss of water from a plant, most often through the stomata in the leaf. The plant hormone
abscisic acid causes guard cells to close the stomata. Plants produce abscisic acid when they lack water.
For abiotic factors affect the rate of water loss/transpiration:




Light: guard cells close stomata during darkness, during day water loss is greater
Temperature: increasing temperature increases evaporation
Humidity: the lower the humidity the faster the loss of water
Wind: increases water loss by removing saturated air from the surface of the leaf
mineral ion transport




Active transport of mineral ions into the root hairs creates a hypertonic environment in the root hair cells
The movement of water also carries with it dissolved minerals, called mass flow
This also creates high water pressure in the roots
Branching of roots and roots hairs increase surface area of the root allowing for enhanced water and
mineral ion uptake
Control of growth
Phototropism:

Growth in response to light
23




Light rays hit the plant stem
Light causes the plant hormone auxin to migrate to the opposite side (shady side)
Auxin stimulates cell division
The shady side of the stem grows faster than the light side causing the stem to bend toward the light
Photoperiodism:

The response to change in length of the night, that results in flowering in long-day and short-day plants
Gravitotropism:


Growth in response to gravity
Roots always grow down regardless of how the seed is placed
Seed germination:




Seed absorbs water
Giberellin activates the gene that produces amylase
Amylase digests starch in cotelydon, producing glucose
Glucose is used for energy for cell division/growth happens (leaf, stem, root)
24
Unit FOUR: Biosphere
1. Describe how the relationships among input solar energy, output terrestrial energy and energy flow within
the biosphere affect the lives of humans and other species
a. explain how climate affects the lives of people and other species, and explain the need to investigate climate
change
b. identify the Sun as the source of all energy on Earth
c. analyze, in general terms, the net radiation budget, using per cent; i.e., solar energy input, terrestrial energy
output, net radiant energy
d. describe the major characteristics of the atmosphere, the hydrosphere and the lithosphere, and explain their
relationship to Earth’s biosphere
e. describe and explain the greenhouse effect, and the role of various gases—including methane, carbon dioxide
and water vapour—in determining the scope of the greenhouse effect
Biosphere:
1.
2.
3.
4.
5.
Another name for the surface of the earth; it is composed of all parts that sustain life
It is composed of 3 divisions
The atmosphere: the layer of air around the earth
The hydrosphere: the water (marine and freshwater) on the surface of the earth
The lithosphere: the land surface not covered by water
Atmosphere:
1.
2.
3.
4.
5.
is composed of 78% nitrogen gas, 21% oxygen gas, and less than 1% argon, carbon dioxide, and numerous
other gases
is divided into several layers, from the bottom up they are: troposhere, stratosphere, ionosphere, and
magnetosphere
the stratosphere (15-50 km) contains the important gas ozone, composed of 3 atoms of oxygen whereas
oxygen gas is only 2 atoms of oxygen. The ozone layer is concentrated around 15-30 km above the earths
surface
Ozone absorbs harmful UV-b radiation preventing most of this radiation from reaching the surface of the
earth. There are 3 types of UV radiation: UV-a is least harmful and not blocked out by the atmosphere, UV-b
is more harmful causing skin cancer in increased exposure, and UV-c the most damaging radiation, which is
totally blocked out by the upper layers of the atmosphere.
Over the last 40-50 years chloroflorocarbons, produced as a propellant for aerosol cans (spray cans and
bottles) has been destroying the ozone layer. UV light in the upper atmosphere decomposes CFC’s releasing
the chlorine atom. This atom will react with ozone, breaking ozone into normal oxygen which does not block
out the UV-b radiation. In the late 1980’s and international ban on CFC’s has slowly had a levelling off effect
on the rate of ozone depletion.
25
The carbon cycle and the greenhouse effect
2.
3.
4.
5.
Carbon dioxide is produced during fossil fuel combustion
Carbon dioxide allows light to pass through but traps reflected heat. This is the greenhouse effect
The greenhouse effect keeps the earth warm and allows life to exist. But too much carbon dioxide can
increase global temp too fast.
This can cause melting of glaciers and icecaps, increasing the level of the ocean, flooding coastal cities,
increased storms, hurricanes, tornadoes, and shifts in global weather and climate
Hydrosphere:
1.
2.
3.
4.
5.
6.
Water covers nearly 75% of the surface of the earth
Most of this water is marine, or saltwater.
Of the freshwater the majority is locked as ice in the polar ice caps
water makes up 70-99% of all living things
it is the major compound in living cells
needed for digestion, transport, cooling, location where reactions occur
Lithosphere:
1.
2.
3.
4.
The land mass of the earth covers about 25% of the surface of the earth
Much of this land mass is not liveable by humans (deserts, icecaps, mountain ranges)
The areas of the lithosphere where life exists are divided into regions called Biomes characterized by dominant
vegetation and associated animal species.
Two major life sustaining processes occur here, and in the oceans. Photosynthesis and cell respiration. (write
chemical reactions)
Energy Flow in Global systems
1.
2.
3.
4.
5.
6.
7.
8.
9.
energy used to sustain life in the biosphere mostly comes in the form of light from the sun.
is generated by fusion reactions in the sun where two hydrogen atoms fuse to form one helium atom. In the
process there is a loss of mass. The mass is converted into energy according to Einstein’s famous equation
E=mc2
The energy released is in the form of the electromagnetic spectrum (gamma, UV, visible, infrared, radio, TV, )
the sun is too far away to feel any heat, plus the vacuum of space prevents heat from being transmitted
through space
the visible light reaches the outer atmosphere and from here down to the earth surface it gets reflected and
absorbed by different parts of the biosphere
is reflected by the upper atmosphere, scattered by the atmosphere and clouds, absorbed by the surface,
absorbed by oceans and used for wind and waves, absorbed by plants for photosynthesis, reflected by the
surface (lithosphere)
Ultimately all energy received by the earth is reradiated back into space in the form of heat. The energy the
earth receives over the long term always balances the energy it gives off. This satisfies the first law of
thermodynamics. The second law of thermodynamics states that when energy is converted from one form to
another the conversion is never 100% efficient. Much of the energy is lost as heat. This is the heat radiated
from the atmosphere, lithosphere, and hydrosphere. Overall energy always flow through a system, it drives
the system. It may be temporarily stored, and given off later, it may be changed from one form to another,
but it is never lost. Energy flows, which in turn causes matter to cycle and life to exist
Examples of conversions that release heat are decomposition and muscle contractions
The suns energy produces life on earth through the processes of photosynthesis and cell respiration. Less
than 1% of the energy that reaches the biosphere is used for photosynthesis. This is the energy that is
transferred through all food chains and food webs. It is the energy that is inside every cell of every living
organism.
26
2. Analyze the relationships among net solar energy, global energy transfer processes—primarily radiation,
convection and hydrologic cycle—and climate.
a. describe, in general terms, how thermal energy is transferred through the atmosphere (i.e., global wind
patterns, jet stream, Coriolis effect, weather systems) and through the hydrosphere (i.e., ocean currents, large
bodies of water) from latitudes of net radiation surplus to latitudes of net radiation deficit, resulting in a variety of
climatic zones
b. investigate and describe, in general terms, the relationships among solar energy reaching Earth’s surface and
time of year, angle of inclination, length of daylight, cloud cover, albedo effect and aerosol or particulate
distribution
c. explain how thermal energy transfer through the atmosphere and hydrosphere affects climate
d. investigate and interpret how variations in thermal properties of materials can lead to uneven heating and
cooling
e. investigate and explain how evaporation, condensation, freezing and melting transfer thermal energy; i.e., use
simple calculations of heat of fusion Hfus= n Q and vaporization Hvap= n Q , and Q=mct to convey amounts of
thermal energy involved, and link these processes to the hydrologic cycle
1.
2.
3.
4.
5.
6.
The energy that reaches the earth’s surface is not always evenly distributed. Variables such as cloud cover,
latitude, and albedo influence the amount of solar radiation that part of the earth receives. This results in
differences in weather and climate at different times of the year in different locations.
Latitude - the position on the Earth relative to the equator. The location on the Earth determines the angle of
incoming solar radiation and therefore the amount of light absorbed, and heat given off, at that latitude.
The latitude of an area on the earth will also influence how much solar radiation that area receives at different
times of the year. The earth is tilted on its axis approximately 23 degrees. As the earth orbits around the sun
this tilt causes the northern hemisphere (as compared to the southern hemisphere) to be more exposed to
the direct rays of the sun for half of the year and then when the earth is in the opposite side of its orbit the
northern hemisphere will be less exposed to the direct rays of the sun for the other half of the year. This
variation causes a warming trend in the Northern Hemisphere, our spring and summer during march to
august, and a cooling trend, our fall and winter during September to February. We know these as the seasons.
The opposite pattern exists in the Southern Hemisphere.
The surface feature of the land often influences how much energy is absorbed. The term used to describe the
amount of light reflected off a surface (hence the amount of energy it absorbs) is Albedo. The higher the
albedo of a surface the less light and energy it absorbs (it reflects more light and is brighter or shinier). An
example is a snow covered field vs an unplanted, dark soil surface. The snow has a high albedo, it reflects a lot
of light, therefore it absorbs very little light, absorbing less energy and heating up slower. The dark field,
however, reflects very little light, absorbing most of the light it receives, absorbing more energy and heating
up faster. This creates “thermals” over dark fields. Thermals are areas of rising air currents created by
warmer, less dense air. Birds, especially predators, are often seen flying/gliding over/in these thermals; the
rising air keeps them aloft with very little wing flapping on the part of the bird.
Clouds have high albedo, consequently the surface below the clouds does not receive as much light as an area
with fewer clouds.
Climate- the prevailing weather conditions of a place as determined by temperature, precipitation, wind,
clouds, and sunlight over a period of years.
27
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
Weather- the general conditions of the atmosphere at a particular time and place. Ex. Temperature,
precipitation, wind, clouds sunlight. Weather systems are driven by the energy from the sun. Both latitude
and surface features on the Earth affect weather and climate.
Thermal energy transfer through the atmosphere: global wind patterns, jet stream, Coriolis effect, weather
systems
Currents in the oceans and atmosphere distribute the solar heating from the tropics to the higher latitudes.
Oceans: act as heat sinks. They store large amounts of thermal energy preventing the earth from getting to
hot, but also release this energy preventing the earth from getting too cold.
Ocean currents: once heated the surface water can be mixed downward or can be moved across by wind.
Surface ocean currents are created by surface wind and their directions are influenced by land masses.
Global wind patterns: are produced by heating at the earth’s surface. The surface heating causes convection
(the circulation and distribution of air). Warm air rises (is less dense) and cold air falls (is more dense). Areas
of cool air form high pressure systems that push air (wind) to areas of lower pressure or warm air.
Weather systems: large air masses of similar air conditions (weather) are created by heating of the ocean. The
air above the ocean warms by conduction and convection creating the air mass. These will move in response
to wind patterns and the rotation of the earth.
Coriolis effect: The rotational movement of the air masses and currents on the earth produced by the rotation
of the earth. The effect is most evident in large systems and is very difficult to produce in small scale systems.
Air masses rotate clockwise in the northern hemisphere and counterclockwise in the southern hemisphere.
Jet stream: currents of extremely fast moving air about 10-15 km above the earth’s surface. They move in a
west to east directions because this is the direction the earth spins. Friction between the earth and the
atmosphere at ground level pulls the air in the direction of rotation.
Gulf Stream: a 100 km wide “river” of ocean water that starts in the Caribbean and goes to Newfoundland. It
follows the east coast of North America
El Nino: a global weather change caused by warm ocean currents moving in different directions than normal.
Ex. Warm pacific water moves north along the west coast of North America creating warmer than usual air
masses in the western U.S and Canada.
Unique properties of water influence climate
High heat capacity: Large amounts of energy are needed to change the temperature of water compared to other
substances. Large bodies of water such as oceans and large lakes have a moderating effect on the air temperature
of nearby land communities. Water temperatures change slowly and by small amounts. Large bodies of water
absorb a large amount of light and heat during the day and during the summer, but release the heat slowly at night
and during the winter.
Phase changes:
Water has high heat of vaporization. This is the energy needed to convert water from a liquid to a gas. The
temperature of the water does not change. For water to evaporate a large amount of energy is needed to break
the attractive forces among water molecules. The opposite occurs during condensation. For water to form a
liquid, it must lose a lot of energy to allow enough molecules to come together and form bonds or attractive forces
to pull the molecules closer to each other. Water evaporates when the molecules absorb enough heat to have
sufficient kinetic energy to break loose from their neighbouring molecules. This heat can be absorbed from
sunlight, from air at the water’s surface, or from other water molecules. When heat is absorbed from other water
molecules, they lose energy and cool. This is known as evaporative cooling and it causes bodies of water to remain
at a relatively stable temperature. When it rains the clouds release this energy causing a slight warming of the air.
Water has high heat of fusion. This is the energy released to convert water from a liquid state to a solid state
(freezing). When water freezes it releases thermal energy, the temperature of the water does not change. When
water melts it absorbs thermal energy but the temperature does not change. In spring, the days become linger
28
and the sun begins to warm the land (the sun rises higher off the horizon, more direct sunlight). If large amounts of
snow and ice remain from the winter, then much of the suns energy is used to melt them. Therefore, the air
temperature does not rise as much as it would in the absence of snow and ice. As winter sets in, the days get
shorter and the sun provides less heat than in summer. As liquid water freezes, however, it releases heat.
Therefore, the air temperature does not drop as much as it would if there were no water to freeze.
Thermal Energy




Also called internal energy
The total kinetic of all the particles in a substance
The sum of all the vibrations and of the particles
Units for energy are in Joules (J)
Kinetic Energy


Is the energy of motion
Is the translational (shaking/vibration) or rotational motion of the particles
Potential Energy



Is stored energy
Produced or stored in the forces between the molecules that determine the state of matter
It is the forces that hold the molecules together in that state
Temperature






The average kinetic energy of the particles in a substance
Different systems are used to measure temperature. These systems are called temperature scales
There are three different scales: Celsius, Kelvin, Fahrenheit
Kelvin Scale: (K) there are no negative temperatures, zero is the lowest. This is the point at which there is
no more motion of the particles; no kinetic energy (0 degrees K). Water freezes at 273 K, boils at 373 K.
Celcius: The lowest temperature is -273 C, water freezes at 0 C and boils at 100 C
K = C + 273
Heat





Is the transfer of thermal (internal) energy
Is measured in Joules (J)
When there is a difference in temperature between two locations thermal energy (heat) will transfer. The
faster movement of particles in one area will bump into the slower moving particles in the other area,
speeding the slow up and slowing fast particles down.
Heat always travels from a hot area to a cold area until it reaches thermal equilibrium
Thermal equilibrium occurs when there is no net transfer of heat, when the two areas are at the same
temperature (all their particles are vibrating with the same speed.
Conduction



The transfer of thermal energy due to the collision of particles (no net movement of substance)
Solids are good conductors b/c particles are more tightly bound allowing for easier collisions.
Metals are the best b/c electrons are more mobile
Convection
29
 The movement of fluid particles from warmer areas to cooler areas
 Occurs best in liquids and gases b/c the particles are more free to move among themselves
Radiation


The transfer of energy in a wavelike form
It does not require a medium to travel through
Calculating Thermal Energy











Is a function of three variables:
Mass, the amount of matter present, the more matter the more energy
Temperature, how fast all the matter or particles are vibrating
Specific heat capacity. The amount of heat (thermal energy) it takes to increase the temperature of 1.0 g
of a substance by 1 degree C
Different substances have different “c”. They have different types and numbers of particles that take
different amounts of energy to move.
Units are J/gC . Ex. Pure water 4.19, aluminum .903, copper 3.85, lead .130
Q = mc ∆ t
Q = thermal energy in Joules or kilojoules
m= mass in g or kg
c= specific heat capacity
∆ t = the change in temp, in Celsius
Heat of fusion





Also called specific latent heat of fusion
The amount of heat required to melt 1 g of a substance. Units are J/g
Heat of vaporization for water = 2260 J/g
This is also the heat given off if the substance freezes.
Q = m Hfus
Heat of vaporization





Also called specific latent heat of vaporization
The amount of heat required to evaporate 1.0 g of a substance. Units are J/g
This is also the amount of heat given off when a substance condenses,
Q= mHvap
Heat of fusion for water = 334 J/g
3. Relate climate to the characteristics of the world’s major biomes, and compare biomes in different regions of
the world
a. describe a biome as an open system in terms of input and output of energy and matter and exchanges at its
boundaries
b. relate the characteristics of two major biomes (i.e., grassland, desert, tundra, taiga, deciduous and rain forest)
to net radiant energy, climatic factors (temperature, moisture, sunlight and wind) and topography (mountain
ranges, large bodies of water)
30
c. analyze the climatographs of two major biomes (i.e., grasslands, desert, tundra, taiga, deciduous and rain forest)
and explain why biomes with similar characteristics can exist in different geographical locations, latitudes and
altitudes
d. identify the potential effects of climate change on environmentally sensitive biomes
Biomes: The biosphere contains many types of ecosystems. The can be divided into terrestrial (land) and aquatic
(water) ecosystems. Terrestrial ecosystems are also called biomes
Tundra
Taiga
Temperate
deciduous
rain forest
Tropical rain
forest
Grassland
Desert
Polar
regions
Immediately
south of
tundra
Midway
between
poles and
equator
Equatorial
Midway
between
poles and
equator
Middle to
equatorial
Very little,
mostly
snow
35-40 cm/yr
snow,
rain,fog
100 cm/yr
snow and
rain
200 and
more cm/yr
25-75 cm/yr
Less than 25
cm/yr
Low, below
zero
Zero to +5
Warmer
than taiga
+20-+25
Similar to
forest but
dryer
Hot during
day cold at
night
Shrubs,
low
flowering
plant, no
trees
Coniferous
trees,
shrubs,
lichens
Coniferous
and
deciduous
trees,
flowering
plants
Lots of trees
and
flowering
plants,
dense
vegetation
Mostly
grasses,
some trees,
some shrubs
Cactus, very
little
vegetation
Rodents,
hares,
caribou
Bison, hare,
moose,
wolves, bear
Insects,
birds, deer,
squirrels
Insects,
birds,
reptiles,
amphibians,
primates
Snakes,
burrowing
animals,
coyotes
Reptiles,
insects,
birds.
Factor
Location
Precipitation
Avg. Annual
temperature
plants
animals
Climatograms
One method of illustrating this variation in energy absorption is through climatograms. A climatogram is a two in
one graph that illustrates the average monthly precipitation and temperature of a given location. The precipitation
is illustrated as a bar graph while the temperature is illustrated as a line graph. Temperature curves that are
higher in the middle of the graph (July and August) are associated with northern hemisphere countries while the
31
opposite is for southern hemisphere countries. Temperature lines that are relatively flat (constant temperature
year round) indicate a tropical location while the steeper the line the more polar the location. Amounts of
precipitation provide an indication of the dominant vegetation that will be found in the location. Consequently,
this provides information about the general types of animals that could be found in the location.
4. Investigate and interpret the role of environmental factors on global energy transfer and climate change
a. investigate and identify human actions affecting biomes that have a potential to change climate and critically
examine the evidence that these factors play a role in climate change
b. identify evidence to investigate past changes in Earth’s climate
c. describe and evaluate the role of science in furthering the understanding of climate and climate change through
international programs
d. describe the role of technology in measuring, modelling and interpreting climate and climate change
e. describe the limitations of scientific knowledge and technology in making predictions related to climate and
weather
f. assess, from a variety of perspectives, the risks and benefits of human activity, and its impact on the biosphere
and the climate
Climate change: a change in the average atmospheric conditions in an area.
Most often this refers to global climate change, but is most often measured in location changes in the patterns of
weather over prolonged periods of time.
Most often measured in changes in average temperatures in the different seasons, changes in rainfall amounts and
distribution, ocean temperatures and different depths, ice depth and range of glaciers and polar icecaps.
Generally most scientists agree that the earth is very slowly warming up. There are some scientists who disagree
and argue that it will be cooling down over the next 100 years.
Role of technology in Climate Change




Ice core samples: atmospheric gases are trapped in ice as glaciers are produced. Analysis of these gases
provides information about carbon dioxide and other gas concentrations in the atmosphere hundreds of
thousands of years ago, depending on how old the ice sample is.
Pollen samples: Pollen are reproductive cells from plants. Finding pollen in soil and ice samples from
thousands of years ago provides information about the types and abundance of plants that grew in an area.
The plants that grow in an area indicate the climate of that area at that time.
Computer models: Use past data from weather and climate patterns to predict future weather and climate,
both short term (tomorrows weather) and long term (climate change of the earth)
Satellite imagery: Determines the temperature, concentration of gases in the atmosphere, tracks storms
development and movement, tracks ocean current and air current movements.
Limitations of scientific knowledge and predictions about weather and climate

Weather and climate are influenced by many large and small scale factors simultaneously, this requires a lot of
information to be processed simultaneously, it is a very complex system.
32


Computer models do not have all the information because we do not fully understand all factors involved
Predictions and conclusions drawn from models are not 100% reliable. Short term predictions of weather are
more reliable (have greater confidence) but long term predictions of weather are not as reliable. Long term
predictions of climate are generally accurate because climate is a general description. Predictions of climate
change and how much change will happen are not as accurate because of the complexity of the system
Human Activity and its impact on the Biosphere and Climate
Human Activity
Risks
Benefits
Combustion of fossil fuels
Increased greenhouse effect and
increased global warming
Jobs for people in communities,
more money for countries for
health care and education.
Loss of ecosystems
Creates business, economic
growth
Species extinction
Damage to cities and human
made structures
Deforestation
Loss of ecosystems
Lumber to be sold
Species extinction
Crops to harvest
Increased global warming
Creates jobs
Soil erosion and damage to
aquatic ecosystems
Money for countries for health
and education
Factors Causing Climate Change and Change in Biomes and Aquatic Ecosystems
Environmental factors:
Continental drift (geological events/processes)
The continents are slowly moving. This causes changes in ocean currents, air currents and precipitation patterns.
This also causes different amounts of light to be absorbed at different latitudes. These changes result in a different
distribution of thermal energy over the biosphere.
Solar cycles
The sun produces different amount of light in its lifetime affecting the amount of light received by the Earth.
Meteors and volcanic eruptions
These produce large amounts of dust and gas that can enhance the greenhouse effect.
Oceans
Absorb and release greenhouse gases thus influencing the greenhouse effect
33
Earth’s Tilt
This varies between 22 and 24 degrees over a 100,000 year cycle. This can affect the amount of light absorbed at
different latitudes and the amounts of thermal energy produced at those latitudes.
Human Factors:
Fossil fuel combustion
Humans are adding large amounts of greenhouse gases by burning fossil fuels (coal, oil, natural gas). Carbon
dioxide concentration in the atmosphere has increased 31% since 1750.
Deforestation
Clear cutting and burning large amounts of forest adds dust and carbon dioxide to the atmosphere. But this also
reduces the earth’s ability to remove carbon dioxide from the atmosphere. Trees, and all other plants, perform
photosynthesis which removes carbon dioxide from the atmosphere.
Evidence for past changes in Earth’s climate
Gases trapped in glacier ice (hundreds of thousands of years old) tell us the concentration of gases in the
atmosphere during that time period
Pollen samples in fossils and plant fossils in old rocks tell us what vegetation was in that area during that time
period. The vegetation tells us indirectly what the climate was like then
Tree rings reflect the growth of the tree in the growing season (summer)
Examining old trees (thousands of years) we can determine how warm the climate has been in the recent past
34
35
Download