1 / 14

Photosynthesis and Chemosynthesis

Photosynthesis and Chemosynthesis. Energy in a cell. Cells need energy to: Grow Reproduce Live Energy for these reactions can be stored in glucose To use energy, though, it needs to be in molecules called ATP. ATP – Adenosine Triphosphate. Energy – carrier molecule 3 phosphate groups

jalila
Download Presentation

Photosynthesis and Chemosynthesis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Photosynthesis and Chemosynthesis

  2. Energy in a cell • Cells need energy to: • Grow • Reproduce • Live • Energy for these reactions can be stored in glucose • To use energy, though, it needs to be in molecules called ATP

  3. ATP – Adenosine Triphosphate • Energy – carrier molecule • 3 phosphate groups • Energy is released when 3rd phosphate group is cut off • ATP  ADP + P + Energy • Released energy is used to power cell activity

  4. Energy from the Sun • Some organisms gain energy from consuming other organisms – called heterotrophs • Other organisms can make their own food – called autotrophs • Plants, algae, and some bacteria capture about 1% of the sun’s energy • convert it to chemical energy through the process of photosynthesis

  5. Photosynthesis Equation LIGHT • 6CO2 + 6H2O C6H12O6 + 6O2 Occurs in the chloroplast of plant cells

  6. Chloroplast Structure • Little “coin-like” structures called Thylakoids • Membrane surrounding thylakoids contains chlorophyll • Stacks of Thylakoids called Grana • Space surrounding Grana is called the Stroma

  7. Photosynthesis Video

  8. Stages of Photosynthesis 2. Light-Independent Reactions (Calvin Cycle) • Light Reactions

  9. Stages of Photosynthesis 1. The Light Reactions • Light energy is absorbed and converted to chemical energy in the bonds of ATP. 1. Light strikes electrons in the chlorophyll 2. Energy from excited electrons used to make ATP molecules 3. Energy now available to do work.

  10. Light Reactions… • Water is split into hydrogen ions, oxygen, and electrons • Electrons replace those lost by the chlorophyll molecule • Oxygen is given off as waste • Hydrogen ions are used to create NADPH (another energy carrier molecule) for use in later steps of photosynthesis

  11. Calvin Cycle Light – Independent reactions • The ‘synthesis’ part of photosynthesis • Takes place in the stroma of the chloroplast • Uses ATP and NADPH from light reactions • Enzymes combine CO2 with hydrogen (from NADPH) and energy from ATP

  12. Light Energy • Light energy has different wavelengths – we see them as different colors • Pigment – a protein that absorbs light • Chlorophyll – a pigment in the chloroplast • Absorbs red and blue light • Reflects green and yellow light – we see that reflected light. • Carotenoids – pigments that make plants yellow and red in the fall ROY G. BIV

  13. Chemosynthesis • Similar to Photosynthesis – but no light! • Inorganic compounds are used for energy to make sugars • Ex: bacteria can do this in the hydrothermal vents at the bottom of the ocean

  14. Chemosynthesis Video

More Related