Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are...
-
Upload
stephen-harrell -
Category
Documents
-
view
220 -
download
0
Transcript of Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are...
![Page 1: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/1.jpg)
Photosynthesis
Chapter 7
![Page 2: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/2.jpg)
Photosynthesis
Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic matter through photosynthesis
Photosynthesis Occurs in chloroplasts Energized electrons are added to carbon dioxide to make
sugar Converts solar energy into the chemical energy of a
carbohydrate Sunlight provides the energy
![Page 3: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/3.jpg)
Anatomy of a Plant
Carried out by the green portions of plants
Leaves contain mesophyll tissue specialized for photosynthesis
Water taken up by roots and transported to leaves by veins
![Page 4: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/4.jpg)
Anatomy of a Plant
Carbon dioxide enters through openings in the leaves called stomata
Light energy absorbed by chlorophyll and other pigments in thylakoids of chloroplasts Main organelle that
carries out photosynthesis!!!!
![Page 5: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/5.jpg)
Chloroplasts Are found in the interior cells of leaves Contain stroma, a thick fluid Contain thylakoids, membranous sacs
![Page 6: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/6.jpg)
Photosynthetic Reaction
Glucose and oxygen are the products of photosynthesis Oxygen given off comes from water
CO2 gains hydrogen atoms and becomes a carbohydrate Reaction written as:
![Page 7: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/7.jpg)
Two Steps…..
1. Light reactions convert solar energy to chemical energy Light-dependent
reactions take place only in presence
of light produce ATP and NADPH
2. Calvin cycle makes sugar from carbon dioxide Light-independent
reactions do not need light to occur result in the formation of
organic molecules
![Page 8: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/8.jpg)
Light Reactions
![Page 9: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/9.jpg)
An Overview of Photosynthesis
Photosystem Starting point of photosynthesis Network of pigments in the membrane of the
thylakoid molecules that absorb light energy primary pigment of a photosystem is chlorophyll pigments act as an antenna to capture energy from
sunlight individual chlorophyll pigments pass the captured energy
between them
![Page 10: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/10.jpg)
How Plants Capture Energy from Sunlight
Light comprised of packets of energy called photons Sunlight has photons of varying energy levels
possible range of energy levels is represented by an electromagnetic spectrum
![Page 11: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/11.jpg)
Human eyes only perceive photons of intermediate energy levels this range of the
spectrum is known as visible light
Chloroplasts absorb select wavelengths of light that drive photosynthesis
![Page 12: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/12.jpg)
The light reactions of photosynthesis Two types of photosystems
cooperate in the light reactions Photosystem II
captures a photon of light and releases an excited electron to the electron transport system (ETS)
Photosystem I absorbs another photon of
light and releases an excited electron to another ETS
![Page 13: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/13.jpg)
Electron transport chain
Connects the two photosystems Releases energy that the chloroplast uses to
make ATP
![Page 14: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/14.jpg)
Calvin Cycle
![Page 15: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/15.jpg)
Calvin Cycle
Light-independent These reactions are the second stage of
photosynthesis Functions like a sugar factory within a chloroplast Regenerates the starting material with each turn NADPH and ATP produced in light reactions used to
reduce carbon dioxide to a carbohydrate
![Page 16: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/16.jpg)
![Page 17: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/17.jpg)
Overview of Photosynthesis
![Page 18: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/18.jpg)
Photosynthesis Versus Cellular Respiration Both plant and animal cells carry out cell respiration
Only plant cells photosynthesize Both processes utilize an electron transport chain
and chemiosmosis for ATP production Photosynthesis reduces CO2 to carbohydrates and
releases O2
Respiration utilizes O2 and gives off CO2
![Page 19: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/19.jpg)
Photosynthesis and Respiration Compared
![Page 20: Photosynthesis Chapter 7. Photosynthesis Almost all plants are photosynthetic autotrophs As are some bacteria and protists Generate their own organic.](https://reader036.fdocuments.in/reader036/viewer/2022062718/56649ebd5503460f94bc5e88/html5/thumbnails/20.jpg)
Environmental Impacts Photosynthesis has an enormous
impact on atmosphere. swaps O2 for CO2
Greenhouses used to grow plant indoors Trap sunlight that warms the air
inside The greenhouse effect
Warms the atmosphere Caused by atmospheric CO2
Greenhouse gases are the most likely cause of global warming Slow but steady rise in the Earth’s
surface temperature Destruction of forests may be
increasing this effect