LEARNING OBJECTIVES By the end of this lecture you will be able to: 1. Understand that ENERGY can be transformed from one form to another. 2. Know that energy exist in two forms; free energy - available for doing work or as heat - a form unavailable for doing work. 3. Appreciate that the Sun provides most of the energy needed for life on Earth. 4. Explain why photosynthesis is so important to energy and material flow for life on earth. 5. Know why plants tend to be green in appearance. 6. Equate the organelle of photosynthesis in eukaryotes with the chloroplast. 7. Describe the organization of the chloroplast. 8. Understand that photosynthesis is a two fold process composed of the light-dependent reactions (i.e., light reactions) and the light independent reactions (i.e. Calvin Cycle or Dark Reactions).
9. Tell where the light reactions and the CO2 fixation reactions occur in the chloroplast. 10. Define chlorophylls giving their basic composition and structure. 11. Draw the absorption spectrum of chlorophyll and compare it to the action spectrum of photosynthesis. 12. Define the Reaction Centers and Antennae and describe how it operates. 13. Describe cyclic photophosphorylation of photosynthesis. 14. Describe noncyclic photophosphorylation of photosynthesis. THE SUN: MAIN SOURCE OF ENERGY FOR LIFE ON EARTH THE BASICS OF PHOTOSYNTHESIS Almost all plants are photosynthetic autotrophs, as are some bacteria and protists
Autotrophs generate their own organic matter through photosynthesis (c) Euglena (b) Kelp (a) Mosses, ferns, and flowering plants (d) Cyanobacteria Light Energy Harvested by Plants & Other Photosynthetic Autotrophs 6 CO2 + 6 H2O + light energy C6H12O6 + 6 O2
Food Chain THE FOOD WEB WHY ARE PLANTS GREEN? It's not that easy bein' green Having to spend each day the color of the leaves When I think it could be nicer being red or yellow or gold Or something much more colorful like that Kermit the Frog Electromagnetic Spectrum and Visible Light Gamma
WHY ARE PLANTS GREEN? Different wavelengths of visible light are seen by the human eye as different colors. Gamma rays X-rays UV Infrared Visible light
Wavelength (nm) Microwaves Radio waves The feathers of male cardinals are loaded with carotenoid pigments. These pigments absorb some wavelengths of light and reflect others. ht g i
l ted c e l f Re Sunlight minus absorbed wavelengths or colors equals the apparent color of an object. Why are plants green? ted
c fle e R t h g li Transmitted light WHY ARE PLANTS GREEN? Plant Cells have Green
Chloroplasts The thylakoid membrane of the chloroplast is impregnated with photosynthetic pigments (i.e., chlorophylls, carotenoids). THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED Chloroplasts absorb light
energy and convert it to chemical energy Light Reflected light Absorbed light Transmitted light Chloroplast
AN OVERVIEW OF PHOTOSYNTHESIS Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water Carbon dioxide Water Glucose PHOTOSYNTHESIS
Oxygen gas AN OVERVIEW OF PHOTOSYNTHESIS The light reactions convert solar energy to chemical energy Light Chloroplast NADP ADP +P
Produce ATP & NADPH The Calvin cycle makes sugar from carbon dioxide Light reactions Calvin cycle Chloroplasts: Sites of Photosynthesis Photosynthesis Occurs in chloroplasts,
All green plant parts have chloroplasts and carry out photosynthesis The leaves have the most chloroplasts The green color comes from chlorophyll in the chloroplasts The pigments absorb light energy Photosynthesis occurs in chloroplasts In most plants, photosynthesis occurs primarily in the leaves, in the chloroplasts A chloroplast contains: stroma, a fluid grana, stacks of thylakoids The thylakoids contain chlorophyll
Chlorophyll is the green pigment that captures light for photosynthesis The location and structure of chloroplasts Chloroplast LEAF CROSS SECTION MESOPHYLL CELL LEAF Mesophyll CHLOROPLAST Intermembrane space
Outer membrane Granum Grana Stroma Inner membrane Stroma Thylakoid Thylakoid
compartment Chloroplast Pigments Chloroplasts contain several pigments Chlorophyll a Chlorophyll b Carotenoids Figure 7.7 Different pigments absorb light differently A Photosynthesis Road Map Chloroplast
Sugar used for Cellular respiration Cellulose Starch Other organic compounds Review: Photosynthesis uses light energy to make food molecules A summary of the chemical processes of photosynthesis Chloroplast
Light Photosystem II Electron transport chains Photosystem I Elec tron CALVIN CYCLE Stroma
s Cellular respiration Cellulose Starch LIGHT REACTIONS CALVIN CYCLE Other organic compounds It's not that
easy bein' green but it is essential for life on earth!
Inequality Inequality Incomes Inequality: Incomes Vertical Inequality Difference between the rich and the poor Horizontal Inequality Where people of similar background, status, qualifications, etc. have differences in incomes Inequality: Incomes Caused by: The Labour Market: Differences in education, qualifications, skills,...
Lindley v. State, 635 S.W.2d 541 (Tex. Crim. App. 1982) SNITCH TESTIMONY When reliability of a given witness may well be determinative of guilt or innocence, nondisclosure of immunity deal violates due process.
Most refactoring techniques are fairly straightforward, and there is often really good tool support for these (now) In both the case of code smells and refactoring techniques, there are new ones being "discovered" all the time, so the list of...
Centennial has developed the GNED 500 course, Global Citizenship: From Social Analysis to Social Action, which has been embedded into the model routes of 21 programs. The objective is to integrate GNED 500 to the model routes of all programs.
Change in state (wax melting or hardening) Solutions- dissolving a solid in a liquid. Mixtures- where a new substance is not formed. Solids mixed with solids (adding salt to ice-lowers the melting point) Liquids mixed with solids (sand and water)...