TAKS Review

1
TAKS Review

• Objective 5
• The student will demonstrate an understanding of
  earth and space systems.

2
Plate Tectonics History

• Wegeners theory of Continental Driftcontinents
  move slowly from Pangaea to present day
• Sea Floor Spreadingmagma wells up forcing the
  sea floor apart and forming the mid-ocean ridge
• Theory of Plate PectonicsEarths crust is broken
  into parts called plates that move or float on
  top of the mantle

3
Continental Drift

• Same fresh water reptile fossils along South
  American African coastlines
• Similar rock formations on both the South
  American African coastlines
• Similar glacier evidence on both continents

4
Sea Floor Spreading
5
Sea Floor Spreading Evidence

• Rocks close to the mid-ocean ridge are very
  young and the age of these rocks continues to
  increase the further you get from the ridge
• Iron bearing minerals show a record of Earths
  magnetic field reversing these rocks show the
  same field direction an equal distance on either
  side of the mid ocean ridge

6
Continental Plates
7
Plate Tectonics
Divergent Plate Boundary
Transform Plate Boundary
Convergent Plate Boundary
Trench-formed where one plate subducts under
another
Sea Floor Spreading
Subduction Zone
8
Rift Valley
9
Rotation
Earth rotates or spins on its axis, taking 24
hrs to make one rotation. This is what gives us
day and night.
10
Revolution
The revolution of the Earth around the sun takes
365.25 days. This is what brings us the seasons.
11
The Moon

• Rotates on its axis once every 29 days
• Revolves around the Earth once every 29 days
• Therefore, we always see the same side of the moon

12
Moon Phases

• We see the moon because it reflects light from
  the sun
• phases caused by moons revolution around the
  Earth
• phases are named for the lit portion of the moon
• Waxing getting lighter Waning getting darker
• Crescent Gibbous refer to the shape of the
  light being reflected

New Moon no reflected light Full Moon full
circle of reflected light
13
Precipitation
Condensation
Evaporation
Runoff Groundwater
Evaporation
14
Water Cycle
The SUN is the driving energy force of the water
cycle
Precipitation can be in the form of rain, sleet,
snow, or hail
Condensation the formation of clouds
Water on the ground can either RUNOFF into
streams, rivers, lakes, etc. or percolate through
the soil to become GROUNDWATER
Evaporation liquid water to gaseous water or
water vapor
15
Renewable vs. Nonrenewable

• Renewable resources are replaced naturally in a
  relatively short period of time (such as plants)
• Nonrenewable resources cannot be replaced as they
  are used (such as iron fossil fuels)
• Inexhaustible resources are renewable resources
  with an almost limitless supply (such as wind and
  sunlight)

16
Endangerment of Species

• Can result from human activities having negative
  effects on the environment
• Modification of the water, nitrogen, and/or
  carbon cycles
• Not only can these lead to species endangerment,
  but also extinction

17
For Example

• Deforestation the destroying and cutting down of
  forests
• Loss of habitat for millions of species results
  in their extinction
• Fewer trees to take in CO2 and trees are burned
  producing even more CO2
• Annually, there is an approximate net loss
  (difference between trees cut down and those
  planted) of 23.2 million acresthats like
  cutting down a little more than an acre of trees
  for every single person in Texas. (about the size
  of a football field)

18
For Example

• Modifying the Carbon Cycle by increasing the
  amount of CO2 in the air from the burning of
  trees and fossil fuels for electricity and
  vehicles of transportation
• CO2 is a greenhouse gas by increasing the levels
  of CO2, it acts as a blanket on the Earth
  raising the average global temperature
• On a global scale C02 makes the biggest
  contribution to global warming (about 64). The
  C02 concentration in the atmosphere is now about
  30 higher than 200 years ago. If it continues to
  increase at the same rate it could nearly double
  by the year 2035. Burning of oil, coal and
  natural gas and the clearing and burning of
  vegetation are the main causes of the increased
  levels of this gas.

19
For Example

• Modifying the Nitrogen Cycle can result in the
  formation of nitric acid and ground-level ozone
• Human health concerns include effects on
  breathing and the respiratory system, damage to
  lung tissue, and premature death. Small particles
  penetrate deeply into sensitive parts of the
  lungs and can cause or worsen respiratory disease
  such as emphysema and bronchitis, and aggravate
  existing heart disease
• Nitrogen pollution can result in acid rain
  causing the destruction and possibly extinction
  of native plant species which in turn can lead to
  the extinction of those animal species that
  depend on the native plants

20
For Example

• Demands for water both for consumption and
  irrigation continue to rise faster than the
  population rate
• Use of rivers causes the flow to be reduced
  downstream and lakes to dry up resulting in a
  loss of habitat for native species
• Pumping out of water from groundwater sources
  such as aquifers leads to land subsidence
  destroying habitat
• Rising levels of pollution in water result in
  less consumable water by living organism causing
  loss of habitat and possible extinction of
  species
• Draining of water-covered lands such as swamp
  lands also result in habitat destruction and loss
  of species

21
Reminders

• Plate tectonics is the movement of crustal plates
  which can lead to sea floor spreading, formation
  of rift valleys, mountain building, and other
  landform changes
• The moon goes through a cycle of changes both
  visually (phases) and forces acting on the Earth
  (tides)
• Species endangerment/extinction can be the result
  of human activities as well as natural events
  modifying natures cycles
• Energy from the sun drives our weather as is an
  almost inexhaustible resource
• Any questions???