Photosynthesis
Autotrophs vs. Heterotrophs Autotrophs “self-feeders” – make own food from inorganic nutrients
Autotrophs vs. Heterotrophs
Heterotrophs “other-feeders” – cannot make food from inorganic nutrients
How Cells Gain Energy From Food
Animal & Plant Cells
The Importance of PhotosynthesisOnly three plants stand between humanity and starvation.
Photosynthesis
Process that transforms simple molecules (CO2) into more complex molecules (carbs) using H2O, minerals & sunlight
Watch Amoeba Sisters Photosynthesis and the Teeny Tiny Pigment Pancakes
Photosynthesis
CO2 and H2O are the end products of what process?
Where did the hydrogens (electrons) in water go?
How is energy being transformed?
What is the fate of glucose?
What do plants need in order to photosynthesize?
Photosynthesis is driven by visible light
What colors are absorbed?
What color is reflected?
Why are plants green?
Chloroplasts – where photosynthesis occurs
Contain pigments that absorb light
Chloroplasts – where photosynthesis occurs
Thylakoids –inner network of membranes
Stroma – liquid material inside chloroplast
What part of a plant contains the most chloroplasts?
Leaves!
LeafStomata – pores on leaf that let CO2 in & oxygen and water vapor out
Where are stomata located? On the top or underside of the leaf? Why?
2 Stages of Photosynthesis
Light Reactions
Where does this step occur in a chloroplast?
INPUTS?
OUTPUTS?
H2O + light energy O2 + NADPH + ATP
Solar energy to chemical energy!
Calvin Cycle
Where does this step occur in a chloroplast?
INPUTS?
OUTPUTS?
Does this step need light?
NADPH + ATP + CO2 glucose
What happens to glucose now?
Cellular resp.
Starch
Cellulose
Fate of Glucose?
Photosynthesis produces our planet’s oxygen as well as 155 billion tons of biomass each year (about 25 tons for every person on earth)!
View this Bioflix animation on Photosynthesis
Variations of Photosynthesis (C3, C4, and CAM) in Different Climates
Plants must open their stomata in order to take in _____________ for photosynthesis.
When plants do this, _____________ escapes.
If a plant lives in a hot, dry environment, it must conserve its water by_______________________.
So how will it take in carbon dioxide?
Variations of Photosynthesis (C3, C4, and CAM) in Different Climates
Visit the website http://wc.pima.edu/~bfiero/tucsonecology/plants/plants_photosynthesis.htm
Using Photosynthesis to Fight Climate Change?
http://instruction2.mtsac.edu/jkido/Biology%201/Lec%20Handouts%20&%20Articles/Exam%202/The%20Ocean's%20Invisible%20Forest.pdf
Watch the video “Capturing Carbon”(After clicking on the “play” button, scroll forward to time stamp 27:53 in order to watch this video)
An 8th-grader's science project prompts her scientist dad to develop a new way to pull excess CO2 out of the atmosphere.
Watch the video “Algae Fuel”
In the search for alternatives to gasoline, are algae the answer?
How is Climate Change Affecting Life?
https://www.arborday.org/media/zones.cfm
Read the online article “Spring Forward”
The Big Picture: Energy flow in living things