Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Biology http://www.google.com/imgres The Working Cell: Energy from Sunlight Click on: https://www.youtube.com/watch?v=uixA8ZXx0KU • Photosynthesis evolved ~3 billion years ago – It supports most of life on Earth – It is the conversion of sunlight into a usable form of energy • Pigments are molecules that absorb certain wavelengths of light while reflecting others • Chlorophyll is green (what we see) and absorbs violet, red and blue; this is the main pigment of photosynthesis. http://www.google.com/imgres 2 • There are 2 types of chlorophyll (a & b); chlorophyll a is the primary pigment in all plants and algae • The chloroplast is the organelle that is the location of photosynthesis. There are many chloroplasts within the leaf (the main photosynthetic part of the plant). http://www.google.com/imgres 3 Chloroplast • Double membrane (outer & inner) • Chlorophyll: green pigment within • Thylakoids: disk-shaped structures that contain the enzymes needed for photosynthesis • Grana (sing: granum): stacks of thylakoids (allow for greater surface area) • Stroma: fluid within (surrounding thylakoids) 4 http://universe-review.ca/I10-22a-leaf.jpg 5 The general equation of photosynthesis: 6CO2 + 6H2O C6H12O6 + 6O2 Photosynthesis occurs in 2 stages (see fig 8-4): • Light dependent Reactions • Calvin Cycle (a.k.a. light independent or Dark Reactions) http://www.google.com/imgres http://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Simple_photosynthesis_overview.PNG/484pxSimple_photosynthesis_overview.PNG 6 Photosynthesis Light Dependent Reactions: • These are also known as the Light Reactions • These require light • These require water and sunlight http://www.google.com/imgres 7 What happens? • Light enters the chloroplast • Water is split, releasing O2 (this is what we breathe) • Electrons become available (to make ATP and NADPH for the Calvin cycle) 8 Photosystems • Photosystem I & photosystem II are located w/in the thylakoids. – Light reactions take place w/in thylakoids – Chlorophyll a is located here – Photosystem II is used 1st; then photosystem I http://www.google.com/imgres 9 The Calvin Cycle: • This is a.k.a. the light independent or dark reactions • This requires CO2 (makes the sugar) http://www.google.com/imgres • This requires ATP and NADPH (which “drives the cycle) 10 http://www.google.com/imgres 11 • 1 glucose is produced for every 6 molecules of CO2 that enter the Calvin Cycle • Actually G3P (glyceraldehyde-3phosphate) is the product of 1 turn of the Calvin Cycle 12 Global Impact • Carbon cycle: process of C changing from inorganic to organic; movement of Carbon through the ecosystem. • Greenhouse effect: when atmospheric CO2 rises, trapping heat within the Earth’s atmosphere causing the global climate to be warm enough for life (the temp is rising). 13 • Primary Production - The conversion of inorganic carbon, usually in the form of carbon dioxide, into organic compounds by autotrophs. 14 A http://amoebasisters.tumblr.com/post/152737982341/a-little-science-funny-to-help-keep-photosynthesis?is_related_post=1 15 Click on link to review: http://www.mhhe.com/biosci/bio_animatio ns/02_MH_Photosynthesis_Web/index.ht ml THE END! 1/12/2017 Template copyright 2005 www.brainybetty.com 16 • • This slide show was developed by Dana Halloran, Cardinal Mooney High School, Sarasota, FL. • • • Used with her personal permission, adapted and amended by Rosa Whiting, Manatee School for the Arts, Palmetto, FL.