Chapter 11: Photosynthesis Flashcards
What is the balanced equation for photosynthesis?
6CO2 + 6H2O —— C6H12O6 + 6O2
What is photosynthesis?
The production of glucose and oxygen using carbon dioxide and water using light energy trapped by chlorophyll
What are 4 benefits of photosynthesis?
Plants use it to make food
Animals get food from plants
Oxygen is produced
Removes carbon dioxide from the air
What are the sources of carbon dioxide?
Atmosphere- stomata in leaves
Respiration - mitochondria
What is the source of water?
Roots - xylem
What is the source of chlorophyll?
Chloroplasts
What happens to glucose once is it made?
Used to get energy
Stored as starch for winter
Turns to cellulose for cell wall
Turned to sugar and travels through xylem (sap)
What happens to oxygen once it is made?
Used in respiration
Released to atmosphere
What are the five main events in photosynthesis?
- Light is trapped - chlorophyll
- Water is split - photolisis
- Fate of Products of split water
- Light energized electrons
- Glucose is formed
What are 4 difference between photosynthesis and respiration?
Photosynthesis: occurs in chloroplasts Uses ATP to make glucose Products are glucose and oxygen Happens in plants and some bacteria
Respiration: Occurs in mitochondria Used glucose to make ATP Products are ATP, CO2, H2O All organisms use it
What are the products of photolysis?
4 low energy electrons
4 hydrogens
Oxygen
What is the fate of the products of photolysis?
Electrons pass to chlorophyll to be energized
Protons (hydrogen ions) are stored in chloroplasts used to convert NADP+ to NADPH
Oxygen is released
What makes glucose?
High energy electrons
Stored protons
Carbon dioxide
What is the stroma?
The empty space around the chloroplasts
What is the grand?
The discs of chlorophyll
What is a thylakoids?
Collection of discs of chlorophyll
What is the light stage?
Occurs in grana
Not controlled by enzymes
Light absorbed by pigment clusters in chloroplasts
Light energy passed to electrons
Energized electron passed to electron acceptor which sends it down one of two pathways
What is the dark stage?
Occurs in stroma
CO2 reduced to glucose
Used energy from breaking down ATP to ADP +P
Uses hyrdrogen and electrons from breaking down NADPH to NADP+ + 2electrons + Hydrogen
ADP and NADP+ returns to light stage to be reused
What is reduction?
Adding electrons to something
What are the two pathways in the light stage?
Pathway 1 - cyclic electron flow
Pathway 2 - non cyclic electron flow
What is pathway 1?
High energy electrons pass from the first electron acceptor to a series of others and back again to the chlorophyll to be energized
As they move around they lose energy to add P to ADP
What is pathway 2?
2 high energy electrons are added from chlorophyll to electron acceptor and then along a series of acceptors
They lose energy to make ATP
eventually the two electrons are passed to combine with NADP+ to form NADP-
Chlorophyll is now short of electron
It gains them through photolysis
The protons stored in the proton pool are attracted to NADP- and combine to form NADPH
What does the light stage include?
Phosphorylation
Photolysis
What does the dark stage include?
CO2 reduced Oxygen removed Hydrogen ions added Electrons added Glucose formed
What are the end products of
The light stage?
ATP - both pathways
NADPH - pathway 2
OXYGEN - pathway 2
What plant is used in the experiment?
Elodea
How is the rate of photosynthesis measured?
Counting bubbles
What gas is produced through experiment?
Oxygen
What is the alternative test for this gas in experiment?!
Light it with a splint hear a pop
How can the temperature be kept the same?
A water bath
How can the carbon dioxide concentration be kept the same?
Excess sodium hydrogen carbonate
2 ways humans intervene in photosynthesis?
Artificial light sources
Artificial carbon dioxide concentration
