Chemosynthesis
Objective: compare the features of photosynthesis and chemosynthesis
How various organisms living in the depth
ocean are able to produce a food?
• No light - ? How to get food?
Chemosynthesis
Bacteria live close to mussels,
they have symbiotic relationship
Mussels = молюски
Sugars are made
• Hydrogen sulfide
• Water
• CO2
Reduced Carbon
Compounds:
Example – (CH2O)
Compare
Chemosynthesis
Where does the energy to fuel this
process come from?
Where does it occur?
What kind of food is made?
What else is formed as a result of
the reaction?
Photosynthesis
Compare
Chemosynthesis
Photosynthesis
Where does the energy to fuel this
process come from?
Hydrogen sulfide from the
hydrothermal vents
Sunlight
Where does it occur?
Bacteria
Plants
What kind of food is made?
Sugars
Sugars
What else is formed as a result of
the reaction?
Sulfur and water (S and H2O)
Oxygen (O2)
Chemosynthesis
• Autotrophic nutrition
• Energy is stored in the form of ATP
• Energy source – redox chemical reactions
• Only some bacteria and archaea make chemosynthesis
• Cell do not contain chlorophyll
• Carbon source: CO (carbon monoxide), HCOOH (formic acid),
CH3OH (methanol), acetic acid (CH3COOH)
Iron-oxidizing bacteria
• Iron-oxidizing bacteria are chemotrophic bacteria that derive
the energy they need to live and multiply by oxidizing dissolved
ferrous iron.
• They live in fresh and marine water
Nitrifying bacteria
• Nitrifying bacteria convert the most reduced form of soil
nitrogen, ammonia, into its most oxidized form, nitrate and get
energy from it
Sulfur bacteria
• any of a diverse group of microorganisms capable of
metabolizing sulfur and its compounds to get their energy
Check yourself – Formative Assessment
• What is the main purpose of chemosynthesis?
A.
B.
C.
D.
To make chemicals
To make food
To make oxygen
To make sunlight
What are the reactants of chemosynthesis? Reactants
are the things needed for a process to occur. (Select
ALL that apply)
A.
B.
C.
D.
E.
sunlight
hydrogen sulfide
oxygen
carbon dioxide
water
What is chemosynthesis?
A. Where bacteria use light energy to make glucose.
B. Where plants use light energy to make glucose
C. Where bacteria use chemical reactions to make glucose
What is the source of energy for chemosynthesis?
A.Light energy
B.Chemical energy
C.Kinetic energy
Where are the places that sulfur bacteria live?
A. Near deep sea volcanic vents and inside tube worms.
B. In soil and roots of some plants
C. Near volcanic vents and in soil
What do we mean by a symbiotic or mutualistic
relationship?
A. Where 2 living organisms live close together and only 1 organism benefits,
the other is harmed.
B. Where 2 living organisms live close together and both organisms benefit.
C. Where 2 living organisms live close together and one organism benefits and
the other eventually dies.
Labwork page #39
• Materials
The Floating Leaf Disk Assay for Investigating
Photosynthesis
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