ENERGY

1. ENERGY

2. EATING! When we eat, our food is broken down in our bodies to get energy out.

3. Energy– The ability to do work Where does energy come from?? Food Energy in food comes from? SUN

4. Chemical Energy • Living things use chemical energy. • ATP (adenosine triphosphate) – chemical compound that cells use to store and release energy. ***All organisms must have ATP in order to function.

5. ATP • ATP – The universal energy molecule for all cells. • ATP stands for Adenosine Triphosphate • A molecule made of 5 smaller molecules bonded together: • Adenine • Ribose • 3 phosphate groups

6. How does ATP give cells energy? Energy is released by breaking the bonds. ENERGY!!!

7. Energy Cycle • ADP (adenosine diphosphate) – consists of adenine, ribose, and 2 phosphate groups • Energy is continuously cycled in the biochemical pathway as ATP is converted to ADP and then ADP is converted into ATP.

8. It is recharged ADP uses energy and gains an extra P and is recharged back to ATP ADP ATP Energy Energy Adenosine diphosphate (ADP) + Phosphate Adenosine triphosphate (ATP) Partially charged battery Fully charged battery

9. ATP Summary • Energy is released when the phosphate bonds are broken. • Energy is stored (ATP rebuilt) when the phosphate bonds are formed. • ***All organisms must have ATP in order to function.

10. Chemical Reactions are Always Occurring in Cells! • Reactants: Substances that are used during a chemical reaction. • Products: The substances made after a chemical reaction. • The sum total of all chemical reactions occurring in a cell is called the cell’s METABOLISM

11. Energy is taken in, stored and used differently by different organisms

12. Light energy from the sun is used by plants to make glucose in a process called photosynthesis

13. Energy from glucose is used by organisms to make more energy in a process called cellular respiration.

14. Plants and some other types of organisms are able to use light energy from the sun to produce food. • Autotrophs: organisms that make their own food (Ex. Plants) • Heterotrophs: obtain energy from the food they consume (ex. People).

15. Photosynthesis & The Leaf

16. Overview Who?  plants Where?  chloroplast

17. Photosynthesis ** If any of the reactants are missing  photosynthesis will not occur.

18. Pigments – capture light energy • Chlorophyll – the main pigment found in most producers. • Absorbs red and violet light; reflects greens and yellows. • Located in the chloroplasts of plants and algae • Other pigments reflect colors such as reds, yellows, and oranges (leaves and fruits)

19. Inside the chloroplast Thylakoids –membranes that contain chlorophyll and proteins that absorb light Stroma: liquid portion inside chloroplast

21. Two steps of photosynthesis

22. 1. Light Dependent Reactions -Where?  Thylakoid Membranes -What?  Sunlight is absorbed by chlorophyll (excites electrons) and water is split by light. -Why?  to provide ATP for step 2!

23. Light Reactions The “photo” part! LIGHT WATER Purpose: to take sunlight and turn it into chemical energy (ATP) LIGHT REACTIONS Needs chlorophyll! ATP OXYGEN

24. 2. Light independent reactions (Calvin Cycle) (Dark reactions) • Where?  stroma • What?  Takes ATP from step 1 and CO2 and makes GLUCOSE!

25. Calvin Cycle (Dark Reaction) The “synthesis” part CARBON DIOXIDE ATP Purpose: to take carbon dioxide and make glucose CALVIN CYCLE GLUCOSE

26. CO2 H2O Light NADP+ ADP P i Light Reactions Calvin Cycle ATP NADPH Chloroplast [CH2O] (sugar) O2

27. Photosynthesis (continued) CO2 Light Dependent Light Independent 1._____________ 2._____________ REACTION REACTION (Calvin Cycle) NEED: NEED: PRODUCES: PRODUCES: PURPOSE: PURPOSE: Light / water ATP / CO2 Oxygen / ATP glucose H2O To change light to chemical energy ATP To make glucose From ATP and CO2 O2

28. Photosynthesis • Who  Plants • Where  Chloroplast • Job – to make food and oxygen • Plants take in….water, carbon dioxide, sunlight • Plants put out….oxygen, glucose

29. CO2 O2 Light H2O Sugar O2 H2Oand minerals CO2

30. Adenine Phosphate Ribose P P P #1 Source of Energy = _____________ Photosynthesis Cell Energy = _____________ “ ____________ ____________” Who  Where  Job to make __________+__________ Energy stored in bond Plants take in • . • . • . Plants put out • . • . ENERGY Release Energy  Store Energy  Remove –P leaves A-P-P ADP Reactant (in) Product (out) Which has more Energy? ____________ Why- Sun E  Chem EFood E Made in the ____________________

31. Adenine Phosphate Ribose P P P Sun #1 Source of Energy = _____________ Photosynthesis ATP Cell Energy = _____________ “ ____________ ____________” Adenosine triphosphate Who  Plants Where  Chloroplasts food oxygen Job to make __________+__________ Energy stored in bond Plants take in • . • . • . Plants put out • . • . ENERGY Release Energy  Break bond O2 CO2 Store Energy  H2O C6H12O6 Make bond Sun E Remove –P leaves A-P-P ADP Reactant (in) Product (out) Remove –P leaves A-P AMP 6CO2 + 6H20 + E  6O2 +C6H12O6 ATP Which has more Energy? ____________ Why- More P-P bonds Sun E  Chem EFood E mitochondria Made in the ____________________

32. Leaves and leaf parts

34. Mesophyll Ground tissue in leaves (meso = middle, phyll = leaf) Contains chloroplasts

35. Mesophyll Mesophyll

36. Xylem and Phloem Xylem – carries water Phloem – carries nutrients

38. Stomata (singular – stoma) Tiny openings in the underside of the leaf – function – gas exchange!

40. Guard Cells Cells that open and close the stomata

41. Fig. 36-16

42. Guard cells turgid/Stoma open Guard cells flaccid/Stoma closed (a) Changes in guard cell shape and stomatal opening and closing (surface view)

44. Epidermis Outer layer of leaf cells.

45. Cuticle Waxy covering of leaf

47. Factors that affect the rate of photosynthesis Amount of sunlight Amount of water Amount of carbon dioxide

48. Chemosynthesis Chemosynthesis: The process by which some organisms, such as bacteria, produce energy through a chemical reaction. Ex. Organisms found near deep sea hydrothermal vents use hydrogen sulfide coming out of seafloor in vent fluids to create energy. Equation: Hydrogen sulfide chemosynthesis: CO2 + O2 + H2S → CH2O + S + H2O

49. How do our bodies take food and make it into energy?

50. What types of organisms undergo cellular respiration? Cellular respiration occurs in ALL living cells!