Transcript Presentation

AHSGE Review for
Science
From Passing the Alabama
Graduation Exam in Science from The
American Book Company
Scientific Process
• Analysis - separation of parts or facts to determine their
relationship to each other
• Assimilation - process of gathering facts and information
about an event or phenomenon for the purpose of
understanding it
• Conclusion - judgement or inference made based on
observation and experimentation
• Control Group - situation maintained in an experiment in
which no variable conditions are introduced
• Data - collection of observed and measurable results
• Deductive reasoning - using a generalization that can test a
hypothesis or theory to deduce or predict a specific event or
phenomenon
Scientific Process cont.
• Experiment - process designed to yield measurable results
about a hypothesis under carefully controlled conditions
• Experimental Group - selected variable conditions for
experimentation to support or reject a hypothesis
• Hypothesis - possible explanation or educated guess given as
a solution to a problem
• Inductive reasoning - using specific observations and
measurements to enable a scientist to arrive at a generalized
explanation of a scientific problem which can be expressed as
a hypothesis or theory
• Observation - noticing an event or phenomenon and
gathering facts about it without manipulation of the evidence
• Prediction - to forecast an event or to anticipate the results of
an experiment
Scientific Process cont.
• Results - the end product of an investigation or experiment
• Science - an exact study by which we acquire knowledge of
the universe
• Scientific Process - method of investigation which follows
logical steps in problem solving
• Theory - complete explanation of how or why something
happens based on research and testing
• Tables are good ways to organize data
• Line graph are best used to show how one variable changes
with respect to another
• Bar graphs are used to show easy-to-read, unconnected, bars
which represent a quantity of information
• Circle graphs are used to show parts of a whole
Steps to the Scientific Method
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1. Define or state a problem
2. State a hypothesis
3. Perform an experiment
4. Collect data from experiment
5. Draw a conclusion for results
6. Make predictions about similar situations
in the future
Atoms and Elements
• Atom - smallest part of an element composed of electrons (e-),
neutrons (no), and protons (p+)
• Electron shell - energy level where electrons are found in
concentration as they move around the nucleus
• Element - atoms that have the same number of protons in the
nucleus
• Ion - electrically charged atoms (loses or gains e-)
• Metalloids - elements that have properties of both metals and
nonmetals (touching zigzag line)
• Molecules - chemically bonded group of atoms (act as unit)
• Metals - have luster, good conductors of heat and electricity,
and have one to three electron is outer shell (left of zigzag)
Atoms and Elements cont.
• Noble gases - elements in the last column of the
periodic chart that are stable and unreactive (gases at
room temp)
• Nonmetals - outer energy shell contains more than four
electrons and they are dull in appearance and do not
conduct heat well (right of the zigzag line)
• Nucleus - central portion of an atom containing no and
p+
• Radiation - transfer of energy by waves as particles are
released from a decaying nucleus
Structure of the Atom
• Atomic Theory - states that all matter is made
up of tiny particles called atoms
• Octet rule - states that the outer shell of
electrons cannot hold more that eight electrons
• Valence electrons - number of electrons in
outer shell of an atom (1, 2, 3, 4, 5, 6, 7, 8)
• Oxidation number - tells how many electrons
an atom gives or takes when it reacts (+1, +2,
+3, +/-4, -3, -2, -1, 0)
Elements
• The number of p+ in an atom gives the atom its identity
• If the number of protons changes, the element changes
• Elements on the periodic chart are arranged according to
their atomic number (# of p+)
• When you add p+ plus no, it is equal to the atomic mass or
mass number
• Atoms of the same element do not always have the same
number of neutrons (isotopes)
• In metals, reactivity increase the further left and down you
go in the chart (most reactive metal if francium)
• In nonmetals, reactivity increases the further right and up
you go (most reactive nonmetal is fluorine)
Elements cont.
• The first column of elements are the Alkali
Metals
• The second column are the Alkaline Earth Metals
• The next to last column are the Halogens
• The small columns in the middle are the
transition metals
• The two bottom rows are the Actinide and
Lanthanide Series (rare earth elements)
Radioactive Elements
• Alpha particles - 2 p+ and 2 no; have a
positive charge; low in energy; can be
stopped by a piece of paper
• Beta particles - 1 e-; negative charge;
medium energy; 1cm of lead can stop
• Gamma rays - wave of energy; no charge,
high energy, thick lead or thicker concrete
can stop
Bonding of Atoms
• Ionic bond - results from transfer of electrons
from one atom to another; very strong bonds; high
melting and boiling points; usually solids at room
temp.; usually between a metal and nonmetal
• Covalent bond - formed when two or more
elements share electrons to create a more stable
outer electron structure; weaker bonds; low
melting and boiling points; between two or more
nonmetals; diatomic molecules form these
Physical and Chemical
Changes in Matter
• Catalyst - substance which speed up a chemical reaction
without being used up in process
• Chemical change - rearrangement of the atoms within
substances to form a product totally different from the
original substance(energy is taken in or given off)
• Physical change - change in form or state of matter in
which the molecular structure of a substance remains
unchanged while the appearance may be altered (most
common is phase changes of matter)
• Products - substances produced at the end of a chemical
reaction
• Reactants - starting substances in a chemical reaction
Physical and Chemical
Changes in Matter
• Surface area - the exposed area of a
substance involved in a chemical change
• Temperature - the degree of average kinetic
energy within a substance which is measured
as heat
• The Law of Conservation of Matter - states
that in a physical or chemical change, matter
is neither created or destroyed
Chemical Changes
• Combustion - a chemical process in which
light and heat are produced
• Fermentation - a chemical change in which
a partial breakdown of substances occurs
without the presence of oxygen
• Electrolysis - the decomposition of a
compound into simpler substances by
passing an electric current through the
compound
Rates of Chemical Reactions
• The addition of a catalyst to a reaction will
cause the reaction to speed up (in the end,
the catalyst can be recovered without
having been changed)
• The greater the surface area of the reactant
substances, the faster the reaction between
two substances will take place
States of Matter
• Physical Characteristics of Matter are
identifying characteristics of matter such as:
color, odor, feel, shape, solubility, hardness,
mass, weight, and taste
• Chemical Characteristics of Matter are
identifying characteristics of matter such
as: atomic structure, density of atoms within
matter, and molecular bonds
States of Matter cont.
• Gas - has no definite shape and no definite
volume (fills any container)
• Liquid - has definite volume and no
definite shape (takes shape of container)
• Solid - has a definite shape and volume
• Matter - a substance existing alone or in
some combination
Characteristics of Liquids
• Viscosity - resistance of a liquid to flow
• Surface tension - tendency of a liquid to
form a “skin” on the surface
• Cohesion - attraction between particles of
the same substance
• Adhesion - attraction between particles of
different substances
Characteristics of Solids
• Malleable - can be hammered into thin sheets
• Ductile - can be drawn into a wire
• Elasticity - can be stretched or bent and
returned to its original shape
• Brittleness - the ease with which a solid breaks
when hammered
• Hardness - is the ability of a solid to resist
being scratched
• Tensile strength - is the resistance of a solid to
break under tension
Transfer of Matter and Energy
Through Biological Systems
• Autotrophs/producers - produce their own food through
photosynthesis
• Heterotrophs/consumers - depend on others for food
• Biotic - living things in an ecosystem
• Abiotic - nonliving things in an ecosystem
• Biological Systems - living organisms which interact with
their environment and perform functions necessary for life
• Cellular Respiration - series of chemical changes within a
cell in which sugar is broken down, oxygen is used, energy
is released, and water and carbon dioxide are produced
Transfer of Matter and Energy
Through Biological Systems
• Decomposers - help to break down and decompose dead
organisms and the wastes of living organisms (fungi &
bacteria)
• Energy - inner cellular power within an organism to carry on
activities necessary to live
• Energy Pyramid - the transfer through feeding levels of a
food chain from producers to various numbers of consumers
• Food Chain - flow of energy and organic material in which
the lowest organisms become food for the next highest
organisms
• Food Web - all the interconnecting food chains in an
ecosystem
Transfer of Matter and Energy
Through Biological Systems
• Matter - anything that takes up space
• Nutrients - materials needed by the cell to live and grow
• Photosynthesis - the process in which a plant makes food
from water and carbon dioxide using energy from the sun
• Herbivores - animals that eat only plants
• Omnivores - animals that eat both plants and other animals
• Carnivores - animals that eat only other animals
• Photosynthesis: 6CO2 + 6H2O
C6H12O6 + 6O2
• Respiration: C6H12O6 + 6O2
6CO2 + 6H2O + energy
Diversity of Life
• Aerobes - organisms that use oxygen to break down food
and release energy
• Anaerobes - organisms that do not use oxygen to break
down food and release energy
• Binomial Nomenclature - a system developed by Linnaeus
for naming living things (Homo sapien or Homo sapien)
• Parasites - organisms that live on or in another organism
and are harmful to that organism
• Plankton - organisms that float on or near the surface of the
ocean
• Saprophytes - organisms that feed on dead matter
• Taxonomy - the science of classifying living things
Taxonomy
• Living things are classified according to their evolutionary
relationships (structure, chemistry, similarities, development,
behavior, nutritional needs, methods of obtaining food, and
DNA)
• Kingdom is the most inclusive classification and species is the
least inclusive
Ex.
• King
Kingdom
Animalia
• Phillip
Phylum
Chordata
• Came
Class
Mammalia
• Over
Order
Primates
• For
Family
Hominidae
• Good
Genus
Homo
• Sport
Species
sapien
Monera Kingdom
• Single prokaryotic cell with a cell membrane and a
cell wall like plants
• Have no membrane-bound organelles or nucleus
• Some contain chlorophyll
• Live in damp places or in water and reproduce by
asexual fission
• Two phylum of monerans: bacteria and
cyanobacteria
• Viruses are often included in this kingdom
Protist Kingdom
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Protists can be single-celled or multicellular
All protists have a nucleus (eukaryotic)
Some have chlorophyll
They can be plantlike (euglenas, diatoms,
dioflagellates, and algae), animal-like (ciliates,
flagellates, sarcodinas, and sporozoa), and
fungus-like (molds, mildews, and rusts)
Fungi Kingdom
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Fungi are saprophytes (parasites)
Have cell walls
Multicellular organisms that are heterotrophic
The body of a fungus, the mycelium, is a mass of
thread-like tubes called hyphae that grow
underground
• Reproduce by spores or by budding
• Like warm, moist places
• Include zygote fungi, sac fungi, club fungi,
imperfect fungi, and lichens
Plant Kingdom
• Angiosperm - flowering plants which develop their seeds in a fruit
or protective structure
• Chlorophyll - green pigment in plants necessary for the process of
photosynthesis
• Deciduous - a broad-leafed plant which loses its leaves in late
autumn
• Evergreen - plant which sheds its leaves and grows new ones
continuously throughout the year
• Gymnosperm - cone-bearing plants which develop their seeds
without a protective covering
• Herbaceous - plant with a soft green stem
• Nonvascular - lacking connective or supporting tissue
• Vascular - network of connected conducting tubes within some
plants
• Woody - hard fibrous stem which supports the structure of plants
Plant Kingdom cont.
• Multicellular organisms with specialized tissues
• Have an organized structure consisting of roots, stems, and
leaves
• Autotropic
• Contain chlorophyll
• Have a cell wall
• Need water, carbon dioxide, and sunlight to produce sugar
and release oxygen
• Bryophytes: Non-vascular spore producing plants
• Tracheophytes: Vascular plants
Basic Parts of a Flower
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Stamen - the male structure of the flower
Pistil - the female structure of the flower
Anther - produces pollen
Ovary - produces the ovule
Stigma - traps the pollen
Style - the tube from the stigma to the ovary
Animal Kingdom
• Invertebrates - animals without a backbone or
internal skeleton; account for 90% of all animals
(porifera, cnidarians, worms, mollusks,
echinoderms, anthropods)
• Vertebrates - more highly developed with small
flexible bones along their dorsal side encasing the
nerve cord (chordata)
• External features - outside appearance
• Internal features - specialized parts of each
phylum are more highly developed than the
previous phylum
Animal Kingdom cont.
• All are multicellular (cells form tissues and tissues
form organs and organs make up organ systems)
• All are heterotrophic
• They grow, reproduce, and develop from larva or
embryos
• They are free moving at some stage of their
development
• Respond to their environments and are capable of
complex reactions to environmental stimuli
• As animal systems become more complex, the organ
systems are more highly developed and specialized
Systems Found in Organisms
• Digestive System - take food into the body and break it
down (mouth, esophagus, stomach, intestines, anus)
• Circulatory System - carry food and oxygen to all the cells
of the organism (heart, arteries, veins, capillaries)
• Respiratory System - supply the body cells with O2 and
eliminate CO2 (trachea, bronchi, lungs, alveoli)
• Excretory System - remove excess H2O and waste products
from the organism (cells, veins, kidneys, skin)
• Nervous System - detect and respond to stimuli in the
environment, controls and coordinates body movement and
body processes (brain, spinal cord, nerve cells, ganglia,
sense organs)
Systems Found in Organisms
cont.
• Muscular System - responsible for body
movement (muscle tissues or cells)
• Reproductive System - produce eggs and sperm
and contain developing embryo (testes, ovary,
uterus)
• Skeletal System - work together to provide
support for the body (bones, cartilage, ligaments,
chitin)
Cells
• Active transport - movement of substances through a
membrane with the use of energy
• Cell - the unit of structure, function, and development
• Chromatin - the substance of which chromosomes are
made: proteins, DNA, and RNA
• Endocytosis - a type of active transport that imports
particles or small cells into a cell
• Eukaryotic cells - having a true nucleus with a nuclear
membrane and organelles
• Exocytosis - a form of active transport by which cells move
molecules, particles, or other cells contained in vesicles
across the plasma membrane to the cell’s environment
Cells cont.
• Gametes - a reproductive cell that contains half the normal
number of chromosomes; a sperm or egg cell
• Homologous chromosomes - pair of chromosomes that
resemble each other in length, shape, and the genes they
carry (one from mother and other from father)
• Meiosis - type of cell division that results in two daughter
cells, each with half the number of chromosomes of the
parent
• Mitosis - type of cell division that results in two daughter
cells that have the same number and kind of chromosomes
as the mother cell
Cells cont.
• Multicellular - an organism that is composed of more than
one cell with each cell having a particular function unique to
the well-being of the organism
• Organelles - parts of the cell whose function are to
contribute to the nourishment, function, and development of
the entire cell
• Passive transport - movement of substances into and out of
a cell without the use of energy
• Plasma membrane - selective permeable, molecular
boundary that separates the cytoplasm of a cell from the
external environment
• Prokaryotic cells - have no organized membrane between
DNA and cytoplasm and no true organelles
Cell Organelles
• Nucleus - control center of cell; storage of hereditary
information
• Endoplasmic reticulum - system of folded membrane in
cytoplasm; protein synthesis and distribution of materials
throughout the cell
• Ribosomes - round-shaped structures in the cytoplasm; sites
of protein synthesis
• Mitochondria - powerhouse of the cell, rod-shaped;
chemical energy conversions for cell metabolism
• Plastids (plants only) - structures that contain chloroplasts;
conversion of light energy into chemical energy, store food
• Golgi complex - flattened membrane sacs; synthesis,
packaging, and distribution of materials in the cell
Cell Organelles cont.
• Lysosomes - type of storage vesicle; digestion, waste
removal
• Microbodies - membranes containing enzymes; chemical
conversions of fats to carbohydrates, discharge of wastes
• Vacuoles - spherical vesicle; digestion, storage, and
elimination
• Microfilaments and Microtubules - fibers and tubes of
protein; movement of internal cell parts
• Cilia and Flagella - short and long extensions of
microtubes from the surface of the cell; locomotion and
production of currents that draw in food
• Centrioles - short tubes near the Golgi bodies; necessary for
cell reproduction within cells
Passive Transport
• Diffusion - move from areas of high concentration to areas of
low concentration
• Facilitated diffusion - special diffusion that occurs when
carrier-proteins in the plasma membrane assist in the passage
of materials into or out of the cell
• Osmosis - movement of water through a semi-permeable
membrane from an area of high water concentration to an area
of low water concentration
• Hypotonic solution - when a cell is surrounded by a solution
that has smaller concentrations of dissolved substances (swell
and burst)
• Hypertonic solution - solution on the outside of the cell is
higher concentration than inside the cell (shrivel and die)
• Isotonic solution - equal concentration inside and outside
Active Transport
• Exocytosis - a form of active transport in
which a cell discharges materials out of the
cell
• Endocytosis - a form of active transport in
which a cell imports substances into the cell
Mitosis
• Type of cell division which generates two
daughter cells with the identical components of
the mother cell
• The daughter cells are identical to each other as
well as the parent cell
• The daughter cells have the same diploid (2n)
number of chromosomes as the parent
• Diploid number is 23 pairs or 46 chromosomes
• Diploid cells are known as somatic cells
Stages of Mitosis
• Prophase - the nucleus of the cell organizes the chromatin
material into thread-like structures called chromosomes;
spindles form between the centrioles
• Metaphase - the chromosomes attached at the center or
centromeres line up on the spindle at the center of the cell
• Anaphase - chromosomes separate at the center, and the
spindles pull them toward either end of the cell; a nuclear
membrane forms around the chromosomes as they
disorganize
• Telophase - chromatin again forms from the chromosomes,
and a cell membrane grows across the center between the
two nuclei
Meiosis
• Type of cell division necessary for sexual
reproduction
• Produces four reproductive cells with half the
number (haploid) of chromosomes of the mother
cell
• Haploid number is 23 single chromosomes
• There are two cell divisions, meiosis I and
meiosis II
• Haploid cells are known as reproductive cells
Heredity and Genetics
• Allele - alternate forms of a gene carried by an individual
• Chromosome - a strand of DNA in the nucleus of a cell
along which genes are located
• DNA - deoxyribonucleic acid, coiled double-stranded
molecules that carry the genetic code
• Dominant - one genetic trait that expresses itself over a
recessive trait
• Gene - the basic unit for heredity found encoded on the
DNA of a chromosome
• Genetics - the study of the passage of biological
information from one generation to the next
Heredity and Genetics cont.
• Heredity - the passing on of characteristic traits from parent
to offspring
• Meiosis - the process of cell division in which cells are
produced that contain only half the number (n) of
chromosomes present in the parent cell
• Mutation - a sudden change in the DNA pattern passed on
to offspring
• Protein synthesis - the process within the cell which
combines amino acids
• RNA - ribonucleic acid, a single-stranded molecule
involved in the manufacture of proteins by a cell
• Recessive - a genetic trait that is suppressed in the presence
of a dominant allele
Genetic Expression
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Alternate forms of a gene are called alleles
Genes can be dominant or recessive
Dominant traits show up over recessive ones
The combination of alleles is the genotype (RR or
Rr or rr)
• The appearance of the trait is the phenotype (round
or wrinkled)
• If you have two like alleles then homozygous
• If two different alleles then heterozygous
Punnett Square
• Used to express the possible combinations
for a certain trait an offspring may inherit
from the parents (shows genotypes)
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T t
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T TT Tt
1:2:1 Ratio
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t Tt tt
25% homozygous tall
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50% heterozygous tall
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25% short
DNA
• The longs strands of DNA are made up of
sugars and phosphates
• Short strands are nitrogen-containing
structures called bases (adenine, thymine,
guanine, and cytosine)
• Adenine and thymine always pair up
• Guanine and cytosine always pair up
DNA cont.
• Replication - the process of making an
exact copy of DNA
• Transcription - the process of making
messenger RNA
• Translation - the process in which transfer
RNA picks up and carries amino acids to
the messenger RNA at the ribosomes
Genetic Mutations
• Mistakes in the duplication of the chromatin material are
called mutations
• Take place in the nucleus of the cell during the replication
process during cell division
• Most are harmful to an organism, few are beneficial
• Gene mutations - mistakes that affect individual genes on a
chromosome
• Chromosomal mutations - mistakes that affect the whole
chromosome
• Mutations in the somatic cells (non-reproductive cells)
affect only the tissues of the organism
• Mutations in the reproductive cells may be transmitted to
the gametes formed in meiosis and passed to offspring
Causes of Mutations
• Radiation exposure can alter sex cells in
humans, which directly affect the offspring
by increasing the number of mutations
• Natural mutation-causing chemicals in food
and human-made chemicals and pollutants
can cause mutations
• Extremely high temperatures can cause
mutations
• Some kinds of viruses can cause mutations
Diseases and Disorders
• Hemophilia - a sex-linked inherited condition involving
failure of blood to clot properly; defective gene is on the X
chromosome
• Down’s Syndrome - a person that has an extra chromosome
that occurred when the DNA replicated at the 21st
chromosome; the extra chromosome interferes with the
normal growth and development of the heart, brain, eyes, and
hands
• Sickle-cell - disease that is an inherited trait in African
Americans; it is a result of two recessive genes
• Phenylketonuria (PKU) - an inherited disease resulting from
a missing enzyme needed to change amino acid phenylalanine
to tyrosine; the phenylalanine builds up in the blood and urine
and caused brain damage
Interdependence of Living
Organisms
• Adaptation - a process by which an organism or species
becomes better suited to a change in its environment
• Communities - the interaction of living things in a given area
• Convergent evolution - a process in which unrelated species
developed similar characteristics
• Divergent evolution - a process by which many different
species developed from a common ancestor
• Ecosystem - an environment made up of biotic and abiotic
interactions
• Greenhouse Effect - temperature increase due to carbon
dioxide buildup in the atmosphere
Interdependence of Living
Organisms cont.
• Pollution - introduction of unwanted or unhealthy materials to
an environment
• Population - the number of individuals of a species in a given
area
• Biosphere - a very thin zone around the earth where living
things are found (contains both biotic & abiotic factors)
• Producers - members of the ecosystem which use abiotic
factors to make and store energy (trees, shrubs, bushes, moss)
• Consumers - members of the ecosystem which depend on
other members for their food (deer, foxes, mice, spiders)
• Decomposers - feed on dead and decaying organisms to
reduce them to the simplest forms (mushrooms, fungi,
bacteria)
Interdependence of Living
Organisms cont.
• Habitat - the dwelling place where an
organism seeks food and shelter
• Niche - an organism’s useful place as a
productive member in the community
• Predator -an animal that feeds on other
living things
• Prey - the animals that predators eat
Symbiotic Relationships
• Commensalism - a symbiotic relationship
in which one member benefits from another,
but no harm is done to the host (barnacles
on a whale)
• Mutualism -a symbiotic relationship in
which two organisms live together in
dependency on each other (protozoa live in
the human intestines)
• Parasitism - a symbiotic relationship that
benefits one organism but harms the other
(tapeworms in humans)
Diseases
• Pathogens - bacteria that causes disease in humans
(tuberculosis, typhus, cholera)
• Antibiotics - used to fight bacterial infections (penicillin)
• Viruses - parasites that use the material of the host cell to
reproduce; cannot grow, reproduce, or carry on respiration
without a host (common cold, pneumonia, polio, measles,
chicken pox, flu, AIDS)
• Vaccines - used to fight viral infections; contain weakened
or dead viruses that no longer cause the disease; vaccine
caused the body to produce antibodies
• Trichinosis - disease in humans caused by the parasite
called trichina worms
Ecosystem and Populations
• Ecological succession - occurs when one community slowly
replaces another as the environment changes
• Climax community - when a few organism establish
themselves and become the dominant species in the area
(prairies or rainforests)
• Primary succession - when the plants and animals of an
ecosystem have reached a stable and balanced biotic
interaction
• Secondary succession - the natural act of reclaiming an area
(native plants will once again reclaim land where crops were
raised)
• Ecological balance - the relationship between the number of
plants in an ecosystem and the number of animals in the
system
Things that change Ecosystems
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Fires
Dams
Mining
Floods
Volcanic eruptions
Dumping chemicals (water pollution)
Acid rain
Air pollution
Transfer of Energy
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Amplitude - height of a wave
Decibel - unit used to measure the intensity of sound
Energy - ability to do work
Frequency - number of waves that pass a point in a given unit
of time
Hertz - measure of wave frequency and vibrations
abbreviated as Hz (1 Hz is one cycle per second)
Kinetic energy - energy of motion
Laser - device that produces a highly concentrated, powerful
beam of coherent light which is all one frequency or color
Photon - particle of radiant wave energy
Pitch - tone of a sound wave, determined by the frequency of
the wave
Transfer of Energy cont.
• Potential energy - stored energy
• Prism - transparent material with two straight faces at an
angle to each other
• Radiation - process of transfer of heat energy by waves from
an area of high temperature to an area of low temperature
• Reflection - bouncing of a wave or ray off a surface
• Refraction - bending of a wave or ray caused by a change in
speed as it passes from one substance into another
• Vibration - rapid back and forth movement of matter
• Velocity - speed of matter in a definite direction
• Waves - rhythmic disturbance which travels through space or
matter
• Wavelength - distance between peaks of a wave
Transferring of Heat
• Heat - the energy transferred between matter as a
result of differences in temperature (increase in
temp increases the particle movement and vice
versa)
• Conduction - kinetic energy is transferred as
particles hit each other (coffee heats up the spoon)
• Convection - in liquids and gases; causes currents
which carry heat upward (mirage)
• Radiation - transfer of heat energy by waves in
space (fireplace)
• Conductors - substances through which heat energy
is allowed to transfer quickly
• Insulators - slow the transfer of heat
Waves
• Transverse waves - up and down movements in
which the motion of the medium is at right angles to
the direction of the wave (water and light waves)
• Longitudinal or Compression waves - a series of
pushes in which the motion of the medium is
parallel to the direction of the wave (sound waves)
• Long wavelength has low frequency and low energy
• Short wavelength has high frequency and high
energy
Earthquake Waves
• Primary (P) waves - compressional waves that
move in push-pull motions similar to sound
waves; travel through the earth and can pass
through solids, liquids, and gases; fastest and first
detected
• Shear (S) waves - called secondary waves;
transverse waves that cause rock to shake
sideways; travel through earth but only pass
through solids; travel about half the speed of P
waves
• Long (L) waves - slow-moving waves which
travel along the earth’s surface; slowest of all
Force and Motion
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Acceleration (m/s2) - change in velocity over time
Force (N) - push or pull exerted on matter
Friction - force between surfaces that opposes motion
Gravity - force of attraction between any two objects that
have mass
Inertia - tendency of an object at rest or in motion to remain
at rest or in motion
Joule - unit of work equal to one Newton meter
Machine - device which can affect force or effort
Motion - change in the position of an object as compared with
a reference point
Newton - unit of force
Force and Motion cont.
• Velocity - speed in a definite direction
• Watt - unit of power equal to one joule per
second
• Work (J) - any process in which matter is
moved by the action of force
• Force (N) = mass (kg) * acceleration (m/s2)
• Weight (N) = mass (kg) * acceleration (m/s2)
Universal Law of Gravity
• Formulated by Sir Isaac Newton
• Every object in the universe pulls on every
other object
• The more mass an object has, the greater its
gravitational force
• The greater the distance between two
objects, the less attraction they have for
each other
Work and Power
• Work is the product of the force applied to
an object and the distance the object moves;
measured in joules
• work (J) = force (N) * distance (m)
• Power is the work done per unit of time
• power (W) = work (J)/time (s)
Newton’s Laws of Motion
• 1st - an object which is moving or at a state of rest
does not change its state of motion unless a force
acts on it; Law of Inertia (a ball will roll in a
straight line until it hits a wall)
• 2nd - acceleration of an object increases as the
amount of force causing the acceleration increases
(if you push two carts with the same force, the
smaller cart accelerates greater)
• 3rd - for every force, there is an equal and opposite
force (when two identical balls traveling at the
same speed collide, they change direction)
Pressure
• Only one kind of matter can occupy a given
space at a given time
• Pressure - force that acts over a certain area
• If pressure on the outside of an object is
equal to the pressure on the inside of an
object, then nothing moves (vacuum cleaner
lowers pressure inside so it can suck up dirt)
• Suction is a result of unequal air pressure
(using a straw to drink coke)