Lecture 2 - Life on Earth PDF

LESSON 2 LIFE ON EARTH Our Home LEARNING OBJECTIVES: 1.Explain the unique characteristics of Earth that are necessary to support life 2.Treasure and take care of the things around you for they are all part of Earth’s life- giving processes. 3.Differentiate each...

LESSON 2 LIFE ON EARTH Our Home LEARNING OBJECTIVES: 1.Explain the unique characteristics of Earth that are necessary to support life 2.Treasure and take care of the things around you for they are all part of Earth’s life- giving processes. 3.Differentiate each subsystems through an activity for the students. MAIN IDEA: The interaction among Earth’s subsystem is vital in sustaining life on the planet. ESSENTIAL QUESTIONS: What are the unique characteristics of earth that allows existence of life? How do Earth’s subsystems affect each other? LESSON 2.1 LESSON 2.1 Some important characteristics that are necessary in supporting life: 1. Presence of liquid water 2. Ability to maintain heat 3. Existence of its atmosphere LESSON 2.1 Presence of liquid water Cyanobacteria The first photosynthetic organisms to thrive Produced biomass and O2, LESSON 2.1 Possible sources of water on Earth: 1. Volcanism 2. Icy meteors bombarded Earth LESSON 2.1 How does Earth sustain water? Habitable zone or Goldilocks Zone The Earth’s distance from the sun wherein it allows Earth to hold water in its liquid form LESSON 2.1 Ability to maintain heat 1. Heat provided by the sun 2. Heat coming from Earth Radioactive decay of materials in the core and mantle and extruded via active tectonic activities Eg. Volcanism, Plate Movement LESSON 2.1 Existence of the Atmosphere Essential to the formation of life on Earth LESSON 2.1 Presence of the Moon Its gravitational pull may have been key to making Earth a livable planet by moderating the degree of wobble in Earth's axial tilt, which led to a relatively stable climate over billions of years in which life could flourish. LESSON 2.1 Tilt of the Axis Changes the amount of light the hemispheres receive, resulting in the changing seasons. LESSON 2.2 Earth’s Subsystems LESSON 2.2 Subsystems – the interacting parts in Earth’s system EARTH’S SUBSYSTEM 1. Geosphere - the solid Earth Composition: minerals, organic material, rocks, and regolith Examples: Mountains, hills Lithosphere – solid outer section Asthenosphere – soft layer where the plates are resting EARTH’S SUBSYSTEM 2. Atmosphere - the mixture of gases surrounding the planet Composed mainly of nitrogen, oxygen, and trace amounts of several gases. Gas Composition  Layers based on EARTH’S SUBSYSTEM Temperature Troposphere Lowest layer Atmosphere Contains 80% of the atmosphere’s total mass Contains all-weather associated clouds The lowest part is the warmest part (temperature decreases as altitude increases) Tropopause 12 km Stratosphere 50 km Above 12 km Tropopause 2nd lowest layer of the atmosphere Presence of ozone Where jet planes fly Almost completely free of clouds and other forms of weather Temperature increases as altitude increases Mesosphere 50 to 80 km the middle layer of the atmosphere Protects earth from meteoroids Temperature decreases as altitude increases Thermosphere the 2nd highest layer of the atmosphere Temperature can rise as high as 1500 0C Ionosphere – layer consisting of highly-ionized gas Kennelly-Heaviside layer – reflects radio waves Temperature increases as altitude increases 80 to 700 km Exosphere the outermost layer of the atmosphere most of orbiting satellites are found contains low density elements (hydrogen, helium) 700 km to 1000km Exosphere EARTH’S SUBSYSTEM 3. Hydrosphere - The totality of Earth’s water It includes the cryosphere (permanently frozen parts) The water in the atmosphere is not part of the hydrosphere. Hydrosphere Nearly 71% of its surface is covered by ocean, the reason why Earth is called blue planet Sea – part of an ocean that is partially surrounding a landform Island sea – totally surrounds a landform Ocean – body of saltwater with almost no boundaries and limitless volume Composition of the Hydrosphere Salinity – the proportion of dissolved salts to pure water, expressed in parts per thousand Sources of salts: chemical weathering, volcanic outgassing EARTH’S SUBSYSTEM 4. Biosphere – The entirety of Earth’s living things; zone of life The global ecological system integrating all living things and their relationship, including their interactions with the elements of the geosphere, hydrosphere, and atmosphere BIOMES The world’s major communities based on the predominant vegetation and are characterized by the adaptation of organisms to a particular climate BIOGEOCHEMICAL CYCLE The pathways by which chemical substances move through biotic or living organism (biosphere) and abiotic or non-living (geosphere, atmosphere and hydrosphere) components of the Earth. It links the four subsystems. UNIFYING/VALUING: Synthesis: How do humans negatively affect the earth's subsystems? What are some of the consequences of these? Meaningful Closure: Can humans alter the environment of Mars to make it suitable for life? Evaluating PETA 1 (by Group): My Own Theory about the Origin of the Universe Goal You are going to illustrate and explain your own beliefs and thoughts on how the universe was created or formed. Role You will play the role of a philosopher. Audience Your audience is composed of a diverse community (both scientific and religious). Situation You are assigned to present your beliefs and thoughts on how the universe was created or formed in front of an audience composed of scientific and religious communities. Product You must either draw manually or create digital art about your thoughts and beliefs on how the universe originated. At the back portion of the illustration, briefly explain what you have drawn or created. Standards Your artwork will be graded based on the specific rubrics provided. Evaluating