Transcript MTTC Elementary Science Review

Life Science
Search “book biology quick review”
Classifying the Diversity of Life
• There are three domains of living things:
Cell Theory
• the cell is the smallest unit of life; all cells arise
from pre-existing cells
Idealized Animal Cell
Idealized Plant Cell
Reproduction and Heredity
Some Terminology
• Same alleles = homozygous
• Different alleles = heterozygous
Homologous
Chromosome Pair
Sister Chromatids
Dominant and Recessive
• In the heterozygous condition, one allele gets
expressed and the other one doesn’t.
• The allele that is expressed is said to be dominant.
• The one that is not expressed is recessive.
Homozygous and Heterozygous
• Homozygous dominant = AA
= dominant trait expressed
• Heterozygous = Aa
= dominant trait expressed
• Homozygous recessive = aa
= recessive trait expressed
Genotype and Phenotype
• Genotype is the set of alleles an individual has for a
character.
• Phenotype is the trait that is expressed.
• Brown eyes is dominant to blue in humans. A
man with brown eyes (whose father had blue
eyes) marries a woman with blue eyes. Predict
the genotype and phenotype frequencies of
their offspring.
Acquired vs Inherited Traits
• Inherited – passed via DNA in sperm/egg from
parents; e.g. eye color
• Acquired – not inherited; e.g. a learned
behavior; strengthening muscles; tattoo
Evolution
When the monster
came, Lola, like the
peppered moth,
remained motionless
and undetected. Harold,
of course was
immediately devoured.
• Morphological adaptation – physical features
• Physiological adaptation – chemical reactions
• Behavioral adaptation - behaviors
Genetic Variation
Overproduction of Offspring
Differential Reproduction
Change in frequency of traits
• Evolution accounts for both the unity (things
in common) and diversity (lots of different
types) of life
Organisms and Their Environment
Behavior
• Learned vs innate behaviors (instinct)
Energy flow and chemical cycling
Physical Science
Atomic Structure
• Matter is anything made of atoms
• States: solid, liquid, gas
• Matter cannot be created or destroyed
• Chemical reaction: Bonds broken, atoms
rearranged
Chemical Reactions
• Chemical reactions - the breaking and making
of bonds; atoms are rearranged (not created,
destroyed, or changed into different elements)
Work
• Work = force x distance
• Energy is the “capacity to do work”
Heat vs Temperature
• Heat is the total energy of molecular motion in a
substance while temperature is a measure of the
average energy of molecular motion in a
substance.
• Heat energy depends on the speed of the
particles, the number of particles (the size or
mass), and the type of particles in an object.
• Temperature does not depend on the size or type
of object. For example, the temperature of a
small cup of water might be the same as the
temperature of a large tub of water, but the tub
of water has more heat because it has more
water and thus more total thermal energy.
• Convection – movement of warmed matter
• Conduction – transfer of energy from particle
to particle
• Radiation – electromagnetic waves transport
energy through space
velocity
acceleration
Acceleration requires force to be applied
Others
• Momentum = mass x velocity
• Work = force x distance
• Gravitation force = mass x gravity
Newton
• Newton 1 – body remains at rest or motion
unless acted on by force
• Newton 2 – Force = mass x acceleration;
objects with greater mass require more force
to move them
• Newton 3 – every action is countered by an
equal and opposite reaction
Simple machine changes the direction or magnitude of force
• Electric current is a flow of electric charge
through a medium. This flowing electric
charge is typically carried by moving electrons
in a conductor such as wire.
magnetic fields are produced by the motion of electrical charges
A circuit is an unbroken loop of conductive material
that allows electrons to flow through continuously
without beginning or end.
If a circuit is "broken," that means its conductive
elements no longer form a complete path, and
continuous electron flow cannot occur in it.
Diff wavelength (frequency), different “color” – different amplitude, different
intensity
Doppler effect – change in frequency of a wave for someone moving
relative to the source of the wave – higher pitch as move toward, lower
pitch as move away
Diff wavelength (frequency), different “color” – different amplitude, different
intensity
THE SCIENTIFIC METHOD
STEP 1
Make
observations.
STEP 2
Formulate a
hypothesis.
STEP 3
Devise
a testable
prediction.
STEP 4
Conduct
a critical
experiment.
STEP 5
Draw
conclusions
and make
revisions.
 The scientific method rarely proceeds in a straight line.
Conclusions, for example, often lead to new
observations and refined hypotheses.
Controlled Experiment
• Control – compare groups with only one
difference – the variable you are interested in
testing (manipulating) – all other variables are
held constant (controlled)
• Replication – multiple subjects in each test
group
Analysis and Communication
• Statistics
• Date in graphs and tables
• Present results to colleagues and the public
Safety
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Goggles and other safety equipment
Disposal and clean up of spills
No eating or drinking in science lab
Etc…
Proper use and care of living organisms
Metric System
• Mass – gram
• Volume – liter
• Length – meter
• Milli – 1000th
• Centi – 100th
• Kilo - 1000
People
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Newton – laws of motion; gravity
Mendel – genetics
Pasteur – airborne disease
Darwin – evolution
Einstein – relativity
Bernoulli – energy in fluids and air