CHAPTER 7 TEST ESSAYS

#1 What is chromatography? Separation of pigments In a solvent according to their densities For plant pigments, we use acetone/ethanol solution Set-up: taper chromatography paper, mark starting point, and put just the tip in the solvent

#1 Chromatography Different months will show different chromatography strips of pigments: SEPT. –mostly chlorophyll LATE OCT.- chlorophyll is gone

Pigments in Leaves carotene-yellow orange chlorophyll a-bright green Xanthophylls-yellow chlorophyll b-khaki green

Why do leaves change color? Chlorophyll breaks down and exposes the other colors that were there all along, but were masked by the green chlorophyll. As fall comes there are shorter days of sunlight Less photosynthesis means less food for plants.

#2 Greenhouse Effect = the capacity of certain gases in the atmosphere to trap heat emitted from the Earth’s surface, thereby insulating and warming the Earth. The Greenhouse Effect (nice little link)The Greenhouse Effect

#2 Man-made Greenhouse UV radiation can enter the glass Glass traps infrared radiation and it heats up Earth’s Greenhouse UV radiation can enter through clouds Infrared radiation get trapped and heats up the earth

Clouds trap the infrared rays If no clouds, the infrared rays go into space.

Man-Made Greenhouse UV rays can enter Infrared rays get trapped inside the greenhouse and warm it

Greenhouse Gases Gases that absorb heat: carbon dioxide Water vapor Methane And cause global warming

#3 Global Warming, increase in the average temperature of the atmosphere, oceans, and landmasses of Earth.atmosphere oceansEarth

Problems with Global Warming Melt polar ice caps and glaciers as well as warm the oceans, glaciers Flooding some coastal regions and even entire islands. Some regions in warmer climates will receive more rainfall than before, but soils will dry out faster between storms.

More Problems with Global Warming This soil desiccation may damage food crops, disrupting food supplies in some parts of the world. Plant and animal species will shift their ranges toward the poles or to higher elevations seeking cooler temperatures, and species that cannot do so may become extinct.

More Problems – Spreading disease – Earlier spring arrival – Plant and animal range shifts and population changes – Coral reef bleaching – Downpours, heavy snowfalls, and flooding – Droughts and fires

Why Global Warming Could be Good Increased photosynthesis for agriculture and forests on a short term basis (some gardeners pump CO 2 in their greenhouses) Some cold climates (like Canada) could have a longer growing season if warmer

Causes of Global Warming Carbon Dioxide from factories, cars (burning of fossil fuels) Nitrous oxides from airplanes’ emissions

USA: Global Warming Hog

#4 Formula: Ozone (O 3 ) GOOD FOR: ozone in the upper atmosphere protects living organisms by preventing damaging ultraviolet light from reaching the Earth's surface O 2 - two oxygen atoms - ordinary common or garden oxygen O 3 - three oxygen atoms - Ozone

Ozone hole over Antarctica

Ozone is thinnest over Antarctica

What are CFC’s? The compounds that contain only carbon, chlorine, and fluorine are called Chlorofluorocarbons, usually abbreviated as CFCs. Banned (by Montreal Protocol) but were usually in aerosols like spray deodorants and making of Styrofoam

Why are CFC’s bad? Chlorine bonds with the oxygen and breaks down O 3 to just O 2 (non-protective layer) So, the earth would be left without the ozone to protect it from harmful radiation

Negative effects of ozone depletion Increased skin cancer and illness due to damaging the immune system Too much UV radiation harming aquatic young Especially harms phytoplankton (microscopic plants) in the oceans which feed a lot of other organisms The Ozone Hole-Ozone Hole Consequences (nice link)The Ozone Hole-Ozone Hole Consequences

Nice Links EEK! - Hole in the Ozone Layer?EEK! - Hole in the Ozone Layer? Antarctic Ozone Hole