Transcript Reviewing for Science

Reviewing for Science
2009 EOG
What is Science



Science is a way of learning about the
natural world.
Scientific theories are attempts to explain
a pattern observed repeatedly in the
natural world. These theories are based
on observations and experimentation.
Scientific Laws describe a repeated
pattern in the natural world.
Branches of Science



Life Science- the study of living systems
and the way in which these systems
interact.
Earth Science- they study of the Earth’s
systems and the systems of space
Physical Science- the study of matter
and energy
Scientific Method






The Hypothesis- a possible explanation based on
what you know and what you observed.
Analyzing Hypotheses- What other explanations
fit with what you have observed
Making a prediction- what do you expect to
happen next
Testing the hypothesis- experimentation
Organizing findings- charting, and analyzing
results of observations and experimentations.
Drawing conclusions- what have you learned
from the process
Laboratory Safety
The Water Cycle
• Precipitation: rain, snow, sleet, hail,
• Surface Runoff- rain water that runs off the
•
•
•
•
•
earth’s surface and returns to the rivers,
lakes and oceans.
Ground Water- the water that in infiltrated
deep into the earth’s surface
Ocean-reserve of water that covers ¾ of the
earth’s surface
Transpiration- the sweating of plants and
release of of water by plants back into the
atmosphere.
Evaporation- the heating up of water
forming gas to return water back into the
atmosphere.
Condensation- the cooling of water vapors
forming clouds in the atmosphere.
Location of Water
•
•
•
•
•
•
Location of water
Oceans
Glaciers
Ground water
Freshwater lakes
Saline Lakes and
Island seas
*Soil water
*Atmosphere
*Streams and Cannels
Total Supply (%)
97.2%
2.15%
0.62%
0.009%
0.008%
0.005%
0.001%
0.0001%
As you can see, humans only have access to about 2% of the total
water supply on the earth. Part of that 2% has been polluted and is
unsuitable for drinking.
Streams
•
•
•
•
•
•
•
•
•
•
Types of Streams
Meandering Streams: streams with many curves
Braided Streams: streams with many channels and islands
*****************************
Drainage Basins: the area of the earth from which streams drain
water
Divides separate drainage basins
Canyon formation: uplift changes the elevation of streambed.
Stream Deposition: Deltas and Alluvial Fans
Deltas form when the streams empties into a body of water
and Alluvial Fans are formed with streams empties on to areas
of flat land
Floodplain: the area of land on either side of the stream that is
underwater during a flood
Lakes and Wetlands
• Types of Lakes
• Natural Lakes: are formed when areas of the earth that are
•
•
•
•
formed by nature such as glaciers depressions, crustal movements
and the fallen tops of erupted volcanoes capture water.
Human Made Lakes: are formed when human made structures
such as dams capture water.
Swamps: are low lying areas near rivers where water is supplied
constantly and is slow moving. Usually are homes to trees.
Marshes: form near lakes with gently sloping shorelines or a river’s
flood plain. Usually is home to grasses or soft bodied plants.
Usually does not house trees.
Bogs: forms in old glacier depressions and rain is its only source of
water. Home to such plants as the pitcher plants and Venus’ flytraps
Water Pollution
• Point Source Pollutants: When pollution
comes from an exact point such as a
drainage ditch or a drain pipe and enters
into the water cycle
• Non-point Source Pollutants: When
pollution enters the water cycle from large
areas such as lawns, construction sites,
farm fields and roads.
Oceans
• The ocean covers ¾ of the Earth’s
surface.
• The ocean provides 70% of the Earth’s
oxygen
• The ocean provides food, medicines, and
salt for the people of the Earth
Composition of the Ocean’s water
• Salinity: the most abundant element in
ocean water is dissolved salts (Sodium
and Chloride ions)
• Salts in the ocean stays balanced even
though rivers, streams and volcano
constantly add new supplies daily.
• Dissolved gases of sea water include
oxygen, carbon dioxide and nirogen.
Surface Currents and gulf streams
• Powerful Winds create surface currents
• Surface currents usually move only the top few hundred meters of
•
•
•
•
•
•
seawater.
The Gulf Stream flows from Florida northeastward toward NC.
Because it originates near the equator it is usually warm.
Currents on the west coasts usually carry cold water.
Density currents form when more dense sea water (cold/salty) sinks
beneath less dense seawater (warm/less salty)
A density current exits in the Mediterranean Sea
Upwelling is a current in the ocean that brings deep, cold water to
the ocean surface. This occurs when strong winds causes surface
waters to move away from the coast.
El Nino occur when winds blowing water from the coast of Peru
slacken and the pacific is warmed and upwelling is reduced.
Waves
• Ocean waves have four parts
• The Crest is the top part of the wave, when the water is at it
•
•
•
•
•
highest point.
The trough is the bottom part of the wave, when the water is at its
lowest point.
Wavelength is the space between one crest to the next crest or one
trough to the next trough.
Wave height the space from the resting position or surface level to
the crest.
The ocean waves does not move the actual water. The water stays
pretty much in the same place.
Breakers: when the energy of the wave reaches the shore it
changes the shape of the wave. Friction of the ocean floor causes
the wave to slow down at the bottom of the wave and the top of
the wave spills over because it is now moving faster than the
bottom of the wave.
Tides
• Tides are caused by the gravitational
attractions between the moon, sun and
the Earth.
• Spring Tide occur when the Moon, the Sun
and the Earth are aligned.
• Neap tides occur when the moon, sun and
the Earth form a right angle.
Ocean ecosystems
• Plankton very small/one celled organisms that float in the ocean
•
•
•
•
•
currents
Phytoplankton-plant life/Zooplankton-animals
Nekton- organisms that actively swim in the ocean current
Benthos-organisms that live on the ocean floor. Most live in the
shallow waters of the continental shelf.
Producers-organisms that produce their own food.
Surface producers-produce food through photosynthesis
Deep water producers produce food through chemosynthesis
Consumers- organisms that depend on producers to survive
Decomposers- organisms that digest dead producers and/or
consumers.
The Sea Floor
• Continental Shelf- gradual sloping end of the continent
•
•
•
•
that extends into the ocean from 10km-350km.
Continental Slope- extends from the end of the
continental shelf to the sea floor
Oceanic trench- deep area at the end of the continental
slope
Abyssal Plain- flat areas on the sea floor that are from
400 m to 600 m below the ocean surface. Can be very
large areas of geography.
Mid-Ocean Ridge- continuous underwater ridge where
new sea floor forms.
Sea Floor Spread- when two crustal plates separate
releasing hot magna creating new sea floor.
Subduction Zone- when one crustal plate sinks beneath
another
Resources from the Ocean
• Petroleum
• Natural gas deposits
• Phosphorite-used to make fertilizer
• Limestone- used to make cement
• Sulfur
• Iron
• Copper
• Zinc
• Silver
Bacteria, Protists and Fungi



Bacteria lives almost everywhere,
air, in food, in water, on things,
under the ground, in and on you
Bacteria have three basic shapesspheres, rods and spirals
Some bacterial have gelatin like
capsule that protect them, some
have an outer “slime layer”
Reproduction and obtaining food and energy






Bacterial usually reproduce by fission by dividing a
cell into two new cells. An asexual reproduction.
Some bacterial make their own food,
(photosynthesis) Most get it from their environment.
Most break down dead organisms, others live as
parasites of living organisms.
Two Kingdoms: Eubacteria & Archaebacteria
The two kingdoms are classified by their cell shape
and structure, types of food obtain and ways to
obtain their food, the waste they produce.
Good and Bad Bacteria




Some bacteria are helpful, others are
harmful.
Good bacterial remove dead material on
the surface of the Earth, recycle nutrients,
remove environmental pollutants,
Help make the foods we eat, help make the
products we use.
Bad Bacteria are pathogen that cause
disease. Some produce toxins or poisonous
substance.
Protist


Protists are a one or many celled
organism that lives in moist or wet
surroundings. Some are plant like
and make their own food, others
are animal like can’t make their own
food, and can move around.
Protists can reproduce sexually and
asexually.
Plant, Animal and Fungus Protists
*Plant-like Protists-make their own food
*Algae-Red, Green, and Brown. Thus called based on the
pigmentation their produce.
• Animal-like Protists-do not make their own food.
• Protozoan classified by their movement.
• Ciliates-move by cilia, short thread like structures.
• Flagellates-moved through a watery environment by
whipping their long flagella.
• Psedopods-move by the use of temporary extensions of
their cytoplasm. (false feet)
• Fungus-like Protists-can not make their own food.
• Slime, molds, mildew
• Eats dead and decaying plants, animals and bacteria
Fungi






Fungus breaks down decaying matter and then
consumes it.
Both sexual and asexual reproduction
Club Fungi-A club shaped structure called a
basidium- a mushroom
Sac Fungi-a sac like structure called asus-yeast,
molds, morels and truffles
Zygote Fungi-Fuzzy black mold-produce round
spore cases called sporangium-molds found on
fruit, bread,
Lichens-a thread like fungus growing with a green
alga or a cyan bacterium-they get their food from
the alga or the cyan bacterium.
Importance of Fungi




Can destroy agricultural plants
Can cause disease in humans and
animals (ringworms, athlete’s feet)
Some fungi can help humans
because their naturally make
antibiotics such as penicillium.
Break down organic material, food
scraps, dead plants and animals
Immunity-Active and Passive





First line of defense for the human body is the
skin, respiratory, digestive and circulatory
systems against pathogens.
Skin-prevents many pathogens from entering the
body
Respiratory system-hair like structures called cilia
and mucus like your nose traps and disposes
most pathogens that do enter the body.
Digestive system-saliva, enzymes, hydrochloric
acid and mucus kill bacteria
Circulatory System-white blood cells destroy
pathogens that have invaded your body
Active or Passive




When your body make some of its own antibodies
to fight off pathogens this is called active
immunity.
When antibodies enter your body that has been
produced in another animal that is called passive
immunity
Some antibodies remain active in your body long
after they have over come the pathogen, to
prevent your body from being invaded again in
the future.
Vaccination is a form of antigens that gives you
immunity against a pathogen, it prevents sickness
does not cure the sickness.
Infectious diseases






Microorganism-can attack the human body the same
way that they ruin foods and wines.
Infectious diseases are caused by bacteria, certain
viruses, protists, or fungi.
Examples-malaria, sleeping sickness, ringworm,
colds, influenza, AIDS, strep throat, measles,
mumps, small pox even swelling of the brain and
lung disease.
Many diseases that are caused by pathogens can be
treated with medicines
An infectious disease can be spread from one
organism to another through direct contact.
Biological vectors are sources that can spread
pathogens from one organism to another. These can
include: rats, birds, cats, dogs, mosquitoes, fleas,
flies and humans
Noninfectious Disease



Disease that are not caused by
pathogens such as allergies,
diabetes, asthma, cancer and heart
disease.
Can not spread from one organism
to another.
Many are chronic which means they
can last for a long time.
How Noninfectious diseases
affect the body



Allergy is an overly strong reaction
of the immune system to foreign
substance.
Diabetes improper levels of insulin
produced by the pancreas. Insulin
regulates how much glucose (sugar)
passes through the blood stream.
Cancer uncontrolled cell growth