ENERGY
The
property
of an
object or
a system
that
enables it
to do
work.
Forms of Energy
Mechanical Energy
Thermal Energy
Chemical Energy
Sound Energy
Electrical Energy
Electromagnetic Energy
Nuclear Energy
Mechanical Energy
Energy of Motion
Examples:
Water flowing in a river
Your legs when you use them to walk
Driving in your car/truck
Mechanical Energy
The energy due to the
position or the movement
of something; potential or
kinetic energy (or a
combination of both).
Potential Energy (PE)
Energy of position, usually related to
the relative position of two things,
such as a stone and Earth, or an
electron and a nucleus.
The kinetic energy of an object is
the extra energy which it possesses
due to its motion. It is defined as
the work needed to accelerate a
body of a given mass from rest to
its current velocity.
Thermal Energy
Energy of moving particles
Anything that is powered by
electricity or gasoline or natural gas
has heat (thermal energy) as a
waste product.
Example: volcano, electric heater,
the sun, light bulb, TV.
Chemical Energy
Energy that is stored in the bonds
that hold atoms together
Examples: energy stored in food,
fuel, batteries
Sound Energy
Produced by vibrations of matter and
travels thru air or other matter as
waves
Examples: speaking to your friends,
a bee buzzing, boiling water, the
horn of a car, clapping your hands
Electrical Energy
Energy of moving electrical charges
Examples: television, hand held
game i.e.
xBox, toaster, microwave, computer,
vacuum cleaner,
]
Electromagnetic Energy
Electromagnetic energy can be
created by moving a loop of wire
through a magnetic field (creating a
current) or vice versa, you can put a
current through a loop of wire and
this will create a magnetic field;
think electric motors
Energy Sources
Common Energy Changes
Transforming Energy
Energy Questions
Possibly expect LOTS of questions
asking you to determine what
type(s) of energy transformations
are taking place
Again you must know the
terminology in order to answer
several other questions
Work
The product of the force on an object
and the distance through which the
object is moved W = F x D, where w
= work, f = force, and d = distance.
( when force is constant and motion
is in a straight line in the direction of
the force).
Measured in joules
Work
Work = Force x Distance
W = F x D
When work is done Displacement
occurs
Work Problem
A lever is used to lift a pallet of bricks. It requires a force of 200
N to lift the pallet of bricks 2.5 meters. How much work is done?
W= F XD
W = 200 N X 2.5 meter
W = 500 Joules
WORK PROBLEM
John’s mother asked him to lift a box
of books to the shelf of her closet
which was 3 meters above the floor.
It required 30 Newtons of force for
John to lift the books. How much
work did he do?
Work = force X distance
Work = 30 Newtons X 3 meters
Work = 90 joules
Force
Any influence that tends to accelerate
an object; a push or pull; measured
in newtons. A vector quantity.
Force = mass X acceleration
( when force is constant and motion
is in a straight line in the direction of
the force).
POWER
Rate at which work
is done or energy
is transformed, or
equal to the work
done energy
transformed
divided by time.
( Measured in
watts)
Power
Power is the rate of work done over
time.
Power = Work / Time
Power = W/T
Power Work and Force
You can expect possibly 1 question
where you will have to use a formula
to determine each of the above
Make sure that you refer to the
formula page in the front of the test
booklet to help you answer these
questions
Macromolecules
Proteins- Made-up of Amino Acids.
Proteins function as enzymes or
structural units.
They do most of the "work" in a cell.
Involved in almost all of the exciting
stuff; metabolism, memory, hormone
action, and movement.
Four Major Macromolecules
Proteins
Carbohydrates
Lipids
Nucleic Acids
4 Primary Elements for Life
C – Carbon
H – Hydrogen
O – Oxygen
N – Nitrogen
These 4 elements are essential for
maintaining life in organisms.
What Do Macromolecules Do?
Macromolecules are made the same way in all
living things, and they are present in all
organisms in roughly the same proportions.
Macromolecules are giant polymers. Poly
means many; mer means units. Polymers
are formed by covalent linkages of smaller
units called monomers; mono means single.
Molecules with molecular weights greater
than 1,000 daltons (atomic mass units) are
usually classified as macromolecules. The
functions of macromolecules are related to
their shape and the chemical properties of
their monomers.
Macromolecules
Carbohydrates- The primary function
of carbohydrates is energy storage
(short- term) also structural
(cellulose)
Proteins
Proteins are
instrumental in the
growth and repair
that takes place in
the body.
Proteins also act
as catalysts to
speed up or slow
down reactions in
the body.
What is an enzyme?
An enzyme increases the rate of a
chemical reaction without being
permanently affected itself.
Let’s put it this way. Suppose your brother and sister are upstairs
doing something they weren’t supposed to do. You go downstairs
and tell your parents what they are doing, and proceed to go to a
friend’s house. Your parents go straight upstairs and punish your
brother and sister without telling them that you told on them. You
acted as a catalyst. They would have been punished anyway, but
you certainly speeded up how fast that punishment occurred.
An enzyme increases the rate of a
chemical reaction without being
permanently affected itself.
Let’s put it this way. Suppose your brother
and sister are upstairs doing something
they weren’t supposed to do. You go
downstairs and tell your parents what they
are doing, and proceed to go to a friend’s
house. Your parents go straight upstairs
and punish your brother and sister without
telling them that you told on them. You
acted as a catalyst. They would have
been punished anyway, but you certainly
speeded up how fast that punishment
occurred.
Lipids
Lipids are fat-like substances that are important parts of
the membranes found within and between each cell and in
the myelin sheath that coats and protects the
nerves. Lipids include oils, fatty acids, waxes, steroids
(such as cholesterol and estrogen), and other related
compounds.
These fatty materials are stored naturally in the body’s
cells, organs, and tissues. Minute bodies within the cells
called lysosomes regularly convert, or metabolize, the
lipids and proteins into smaller components to provide
energy for the body. Disorders that store this intracellular
material are called lysosomal storage diseases. In addition
to lipid storage diseases, other lysosomal storage diseases
include the mucolipidoses, in which excessive amounts of
lipids and sugar molecules are stored in the cells and
tissues, and the mucopolysaccharidoses, in which
excessive amounts of sugar molecules are stored.
Lipids
FATS – are constructed from one glycerol
plus three fatty acids. They separate from
water (Like oil and vinegar salad
dressings). Fats are referred to as
saturated or unsaturated. Saturated fats
have many hydrogen atoms attached by
single bonds. Unsaturated fats have one
or more double bonds, formed by
removing hydrogen atoms from the
carbon skeleton. Unsaturated fats are
better for humans because the double
bonds make it more difficult for the lining
of blood vessels to have deposits of
plaque on those blood vessels
Carbohydrates
Carbohydrates, are sugars that provide the body
with energy. Your body can break carbohydrates
down quickly and efficiently.
Carbohydrate rich foods in their natural state are
low in calories and high in fiber. Carbohydrates
contain about 4 calories per gram. Fat contains
about 9 calories per gram.
The main function of carbohydrates is to provide
your body with energy. Carbohydrates usually
provide about have of your body's energy when
your resting or performing a low-level activity.
Nucleic Acids
There are three functions of nucleic acids: one from a nucleotide, one from DNA,
and one from RNA.
1.) ATP is cellular energy. ATP stands for adenosine triphosphate, and it is a
nucleotide. It is shown below, and you should notice that it looks just like the
AMP image above, except that there are three phosphate groups in ATP. ATP is
what our cells use to do everything that they need to do, it is generated every
time we break down glucose in the presence of oxygen. genetic code.
2.) DNA is our genetic code. As such, what does it do? It contains the
information so that our cells know how to make all the proteins they
need. When there is a genetic problem, like with muscular dystrophy or sickle
cell anemia, the problem is played out with a faulty protein (dystrophin or
hemoglobin in those examples). reading our genetic code.
3.) RNA is used to read the DNA and provide the instructions contained within
the DNA to the rest of the cell so that the cell can make the appropriate
proteins.
Absorption – organisms use absorption to obtain nutrients,
oxygen, and water.
Energy – used by organisms for life processes. Organisms get
energy through photosynthesis and respiration.
Excretion – removal of waste materials from the cell.
Adaptation – inheriting traits that increase an organisms chance
of survival.
Digestion – breakdown of food into particles that can be used
by a cell
Response – ability to react to a stimulus.
Biosynthesis – food is changed into a form that can be used by
organisms to grow, reproduce, and carry on life functions in
general.
Secretion – release of enzymes
Reproduction – asexual or sexual – used to pass genetic
information form parent to offspring.
Macromolecule Questions
Potential to see the info covered in
these slides many times in different
forms
Several questions regarding DNA vs.
RNA
Know the primary function of each
macromolecule