how does a seed grow into a tree? where does all the mass come from???
TRANSCRIPT
![Page 1: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/1.jpg)
How does a seed grow into a tree? Where does all the mass come
from???
![Page 2: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/2.jpg)
Photosynthesis
![Page 3: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/3.jpg)
• Plants convert the energy of sunlight into the energy of chemical bonds of carbohydrates
![Page 4: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/4.jpg)
Importance of Photosynthesis
![Page 5: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/5.jpg)
But that’s not all..
![Page 6: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/6.jpg)
![Page 7: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/7.jpg)
But wait, there’s more..
![Page 8: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/8.jpg)
Photosynthesis:
6 CO2 + 6 H2O C6 H12 O6 + 6 O2
carbon dioxide + water = sugar + oxygen
STARCH
photosynthetic products often stored as starch
•Starch = glucose polymer
![Page 9: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/9.jpg)
CO2+H20 C(H2O)+ O2
Photosynthesis
Respiration
Sun
The BIG Picture
![Page 10: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/10.jpg)
Leaf Structurecuticle - waxy, water resistant
layer on the surface of the leaf
Epidermis - transparent, colourless cell layer below the cuticle
mesophyll cells - pallisade: are elongated cells located just below the epidermal tissue
- spongy mesophyll consists of loosely packed cells where gas exchange takes place
![Page 11: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/11.jpg)
Fig. 10.2a
![Page 12: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/12.jpg)
Leaf structure
![Page 13: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/13.jpg)
Chloroplasts
![Page 14: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/14.jpg)
Fig. 10.2b
![Page 15: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/15.jpg)
Chloroplasts• plant cell organelles where
photosynthesis takes place, found mainly in mesophyll layers in leaves
• have an inner and outer membrane
• the liquid material in the chloroplast is called the stroma
• Stroma contains a series of membrane bound sacs called thylakoids which are stacked on top of one another to form grana
• adjacent grana are linked together by lamellae
![Page 16: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/16.jpg)
• Photosynthesis occurs partly within the stroma and partly within the thylakoid membrane
• The thylakoid membrane contains light-gathering pigments and an electron transport chain
• Thylakoid membranes enclose an interior space called the thylakoid lumen
![Page 17: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/17.jpg)
Overview of Photosynthesis
1. Light reactions2. Dark reactions – Calvin Cycle
![Page 18: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/18.jpg)
![Page 19: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/19.jpg)
The light reaction
• Light energy is being converted to chemical energy in the form of ATP and a reduced electron carrier (NADPH + H+)
![Page 20: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/20.jpg)
Light Reactions
![Page 21: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/21.jpg)
![Page 22: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/22.jpg)
Fig. 10.4
![Page 23: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/23.jpg)
• When light strikes an object it can be:1) Reflected2) Transmitted3) Absorbed
• Substances that absorb light are called pigments
• Different pigments absorb at different wavelengths
![Page 24: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/24.jpg)
![Page 25: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/25.jpg)
Pigments
![Page 26: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/26.jpg)
Chlorophyll
• Chlorophyll is a pigment that absorbs in the red and blue regions of the visible spectrum
• Most of the green wavelengths are reflected so a sample of chlorophyll appears green
![Page 27: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/27.jpg)
Chlorophyll
•Absorbs red & blue light
•Reflects green light
![Page 28: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/28.jpg)
Fig. 10.8
![Page 29: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/29.jpg)
![Page 30: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/30.jpg)
(A) When a molecule absorbs the energy of a photon, it is raised from a ground state to an excited state. (B) In the excited state, an electron is boosted to a more distant shell, where it is held less firmly.
![Page 31: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/31.jpg)
Fig. 10.6
![Page 32: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/32.jpg)
![Page 33: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/33.jpg)
Energy Transfer and Electron Transport - Rather than being lost as fluorescence, energy from a photon may be transferred from one pigment molecule to another. In an antenna system, an excited pigment molecule can transfer energy through a series of other pigment molecules to a pigment molecule in the reaction center. That molecule may become sufficiently excited that it gives up its excited electron, which can then be passed on to an electron acceptor.
![Page 34: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/34.jpg)
Chlorophyll
• Absorbs light and excites electrons• Passes those electrons to an
electron acceptor: NADP+ (nicotinamide adenine dinucleotide phosphate)
NADP+ + e− → NADPH + H+
![Page 35: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/35.jpg)
![Page 36: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/36.jpg)
Energy Storing Compounds
Energy trapped by molecules can be used to lift electrons to a higher energy level.
From that higher energy level the electrons can fall down to their original energy level and do work along the way.
Example – a solar cell that powers a calculator
![Page 37: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/37.jpg)
Or…
The high-energy electrons can be bound to an electron carrier.
Nicotinamide Adenine Dinucleotide Phosphate
NADP+ accepts a pair of high energy electrons and a Hydrogen ion to become NADPH
![Page 38: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/38.jpg)
• light-independent reactions do not use light directly, but instead use ATP, NADPH + H+ (made by the light reactions), and CO2 to produce sugars. There are three different forms of the light-independent pathway that reduces CO2: the Calvin cycle, C4 photosynthesis, and crassulacean acid metabolism.
![Page 39: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/39.jpg)
Calvin CycleProducts from the light reactions
and CO2 from the atmosphere are used to produce carbohydrates
![Page 40: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/40.jpg)
![Page 41: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/41.jpg)
![Page 42: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/42.jpg)
![Page 43: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/43.jpg)
Autotrophs• Self-feeders:
– sustain themselves without eating or decomposing other organisms
• Plants are photoautotrophs– They use light
• Some bacteria are chemoautotrophs– Produce organic
compounds without light from substances such as S or NH3
![Page 44: How does a seed grow into a tree? Where does all the mass come from???](https://reader035.vdocuments.net/reader035/viewer/2022062410/56649ed05503460f94bddd86/html5/thumbnails/44.jpg)
Heterotrophs
• Live on compounds produced by other organisms
• Eat other plants or animals or are decomposers (bacteria or fungi) that eat fallen leaves, feces, dead animals