energy in living systems
DESCRIPTION
Energy in Living Systems. CH 6 pg 112-118. Organisms classified on how they obtain energy. Autotrophs Make their own food from organic molecules Most convert light energy into chemical energy Carbon Dioxide (CO 2 ) and water (H 2 O) to organic compound Oxygen (O 2 ) released Heterotrophs - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/1.jpg)
Photosynthesis and Cellular Respiration Section 2
Energy in Living Systems
CH 6 pg 112-118
![Page 2: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/2.jpg)
Photosynthesis and Cellular Respiration Section 2
Organisms classified on how they obtain energy
• Autotrophs– Make their own food from organic molecules– Most convert light energy into chemical energy
• Carbon Dioxide (CO2) and water (H2O) to organic compound
• Oxygen (O2) released
• Heterotrophs– Cannot make their own food inorganic compounds– Eat autotrophs or other heterotrophs
![Page 3: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/3.jpg)
Photosynthesis and Cellular Respiration Section 2
Photosynthesis
![Page 4: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/4.jpg)
Photosynthesis and Cellular Respiration Section 2
Harvesting Light Energy
• Photosynthetic organisms have chloroplasts– Chloroplasts are the organelles that convert
light energy into chemical energy.• Contains flat, disc-like sacs called thylakoids.
• this is the first stage of photosynthesis.
![Page 5: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/5.jpg)
Photosynthesis and Cellular Respiration Section 2
Thylakoids
![Page 6: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/6.jpg)
Photosynthesis and Cellular Respiration Section 2
• Sunlight composed of ROY G BIV, different colors. (Lgth = Amt of Engy)
• Color observed when light strikes an object, waves are reflected, transmitted, or absorbed
• Colors react depending on the pigment present
Light Absorption in Chloroplast
![Page 7: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/7.jpg)
Photosynthesis and Cellular Respiration Section 2
Harvesting Light Energy, continued
• Chlorophyll (a and b) – Absorbs blue and red light and reflects green
and yellow light• Carotenoids
– help plants absorb additional light energy– absorb blue and green light, reflect red,
orange and yellow(fall colors)
![Page 8: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/8.jpg)
Photosynthesis and Cellular Respiration Section 2
Two Electron Transport Chains• First reaction in photosynthesis is the light reaction takes
place in the chlorophyll– Light hits a thylakoid– Energy is absorbed by the pigment molecules and are
directed to a special chlorophyll molecule that acts as a reaction center
– Electrons are excited and move to other molecules and the electron transport chain.
• One ETC makes ATP and Second makes NADPH
![Page 9: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/9.jpg)
Photosynthesis and Cellular Respiration Section 2
Producing ATP
Step 1:• An enzyme splits water
molecules , e- is released.
• H+ ions stay within the thylakoid
• e- is charged by pigment• Oxygen gas is released
into the atmosphere
1st Electron Transport Chain
![Page 10: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/10.jpg)
Photosynthesis and Cellular Respiration Section 2
Step 2: • Carrier Proteins (ATP
Synthase) in the membrane pump H+ ions into the thylakoid,
![Page 11: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/11.jpg)
Photosynthesis and Cellular Respiration Section 2
Step 3: • Energy diffusion of H+
ions through ATP synthase is used to make ATP
![Page 12: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/12.jpg)
Photosynthesis and Cellular Respiration Section 2
2nd Electron Transport Chain
Step 4: Producing NADPH• Renergizing, Light excites
electrons that are passed on to the second chain.
![Page 13: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/13.jpg)
Photosynthesis and Cellular Respiration Section 2
Step 5: Making NADPH• Excited electrons
combine with H+ ions and NADP+ to form NADPH.
• NADPH is used to store energy in organic molecules. (used later in dark reaction)
![Page 14: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/14.jpg)
Photosynthesis and Cellular Respiration Section 2
Electron Transport Chains of Photosynthesis
Click to animate the image.
![Page 15: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/15.jpg)
Photosynthesis and Cellular Respiration Section 2
Producing Sugar
• The first two stages of photosynthesis depend directly on light to make ATP and NADPH.
• In the final stage of photosynthesis, ATP and NADPH are used to produce energy-storing sugar molecules from the carbon in carbon dioxide.
• The use of carbon dioxide to make organic compounds is called carbon dioxide fixation, or carbon fixation. (Light Independent, Dark Reaction, or Calvin Cycle)
![Page 16: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/16.jpg)
Photosynthesis and Cellular Respiration Section 2
![Page 17: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/17.jpg)
Photosynthesis and Cellular Respiration Section 2
Calvin Cycle
• Carbon Fixation, an enzyme adds CO2 to a five carbon molecule (RuBP)
• Takes place outside of the Thylakoid in the stroma, solution surrounding the thylakoids
![Page 18: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/18.jpg)
Photosynthesis and Cellular Respiration Section 2
Calvin Cycle• CO2 diffuses into the stroma
• The enzyme (RuBP) adds CO2 to a five carbon molecule
• This occurs 3 times to make six carbon molecule
• 6 carbon molecule splits into 2 – 3 carbon molecules (3 – PGA)
![Page 19: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/19.jpg)
Photosynthesis and Cellular Respiration Section 2
G3P
GPAG3P
RuPB
G3P
![Page 20: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/20.jpg)
Photosynthesis and Cellular Respiration Section 2
• Each of 3 – PGA is converted into G3P– G3P is a molecule with additional phosphate and H+
that were donated by ATP and NADPH– ADP and NADP are then recycled to the ETC
• One G3P molecule leaves the Calvin Cycle to be used to make carbohydrates
• The remaining G3P molecules are recycled back to the enzyme RuBP and reenters the Calvin Cycle
![Page 21: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/21.jpg)
Photosynthesis and Cellular Respiration Section 2
G3P
GPAG3P
RuPB
G3P
![Page 22: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/22.jpg)
Photosynthesis and Cellular Respiration Section 2
![Page 23: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/23.jpg)
Photosynthesis and Cellular Respiration Section 2
Factors that Affect Photosynthesis
• Light intensity• Carbon dioxide concentration• Temperature
![Page 24: Energy in Living Systems](https://reader036.vdocuments.us/reader036/viewer/2022062423/5681453d550346895db20618/html5/thumbnails/24.jpg)
Photosynthesis and Cellular Respiration Section 2
Relationship