ESCI Lesson 3 Origin and Structure of Earth.pdf

Earth Science Lesson 3: Origin and structure of the Planet Earth Learning Competency: The learners shall be able to recognize the uniqueness of Earth, being the only planet in the solar system with properties necessary to supp...

Earth Science Lesson 3: Origin and structure of the Planet Earth Learning Competency: The learners shall be able to recognize the uniqueness of Earth, being the only planet in the solar system with properties necessary to support life. (S11/12ES-Ia-b-3) Lesson Objectives: identify the characteristics of the Earth that supports life; and expound how the characteristics of the Earth sustain the needs of a living organism. Earth as habitable Planet Factors that make a Not Enough of the Just Right Too Much of the Situation in the Solar Planet Habitable Factor Factor System Temperature Low temperatures Life seems to be At about 125oC, Surface: only the influences how cause chemicals to limited to a protein and Earth’s surface is in quickly atoms and react slowly, which temperature range carbohydrate this temperature molecules move. interferes with the of -15oC to 115oC. In molecules, and the range. Sub-surface: reactions necessary this range, liquid genetic material the interior of the for life. It can also water can still exist (e.g., DNA and RNA) solid planets and cause the freezing of under certain start to break apart. moons may be in this water, making liquid conditions. Also, high temperature range. water unavailable temperatures cause the quick evaporation of water. Atmosphere Small planets and Earth and Venus are Venus’s atmosphere Of the solid planets moons have the right size to hold is 100 times thicker and moons, only insufficient gravity to a sufficient than Earth’s. It is Earth, Venus, and hold an atmosphere. atmosphere. Earth’s made almost entirely Titan have significant The gas molecules atmosphere is about of greenhouse atmospheres. Mars’ escape to space, 100 miles thick. It gasses, making the atmosphere is about leaving the planet or keeps the surface surface too hot for 1/100th that of moon without an warm and protects it life. The four giant Earth’s, too small for insulating blanket or from radiation and planets are significant insulation a protective shield. small- to completely made of or shielding. mediumsized gas. meteorites. Energy When there is too With a steady input Light energy is a Surface: The inner little sunlight or too of either light or problem if it makes a planets get too much few of the chemicals chemical energy, planet too hot or if sunlight for life. The that provide energy cells can run the there are too many outer planets get too to cells, such as iron chemical reactions harmful rays, such as little. Sub-surface: or sulfur, organisms necessary for life. ultraviolet. Too many Most solid planets die. energy-rich and moons have chemicals is not a energy-rich problem chemicals Nutrients used to Without chemicals to All solid planets and Too many nutrients Surface: Earth has a build and maintain make proteins and moons have the are not a problem. water cycle, an an organism’s body. carbohydrates, same general However, too active atmosphere, and organisms cannot chemical makeup, so a circulation system, volcanoes to grow. Planets nutrients are such as the constant circulate nutrients.  without systems to present. Those with volcanism on Venus, Titan, Io, and deliver nutrients to a water cycle or Jupiter’s moon, Io, or Mars have nutrients its organisms (e.g., a volcanic activity can the churning and ways to circulate water cycle or transport and atmospheres of the them to organisms. volcanic activity) replenish the gas planets, Sub-surface: Any cannot support life. chemicals required interferes with an planet or moon with Also, when nutrients by living organisms. organism’s ability to sub-surface water or are spread so thin get enough molten rock can that they are hard to nutrients. circulate and obtain, such as on a replenish nutrients gas planet, life for organisms cannot exist. Reasons why planet earth is a unique one: 1. It has liquid water; 2. Plate Tectonics; 3. It has atmosphere that shelters it from the worst of the sun’s rays. Planet earth is habitable because: it has the right distance from the sun. It is kept warm by an insulating atmosphere. it has the right chemical ingredients for life including water and carbon. It can provide water, oxygen, useful biological products for human, and has suitable weather and climate. Comparison of the features of Venus, Earth, and Mars (Terrestrial Planet) Similarities: They all are terrestrial planets, made of solid rocks and silicates; They all have an atmosphere; They all almost have the same time to rotate on their axes; Earth and Mars both have water; They all have carbon dioxide; All have landforms. Differences:  Venus has no water; Venus and Mars don’t have oxygen; Earth has life forms.