Chapter 10: Photosynthesis Flashcards
Photosynthesis
- Conversion of light energy to chemical energy that is stored in sugars or other organic compounds
- Occurs in plants, algae, and certain prokaryotes
Autotroph
- Organism that obtains organic food molecules without eating other organisms or substances derived from other organisms
- Use energy from the sun or from the oxidation of inorganic substances to make organic molecules from inorganic ones
Heterotroph
Organism that obtains organic food molecules by eating other organisms or substances derived from them
Mesophyll
- Leaf cells specialized for photosynthesis
- In C3 and CAM plants, located between the upper and lower epidermis
- In C4 plants, they are located between the bundle-sheath cells and the epidermis
Stomata
- Microscopic pores surrounded by guard cells
- In the epidermis of leaves and stems that allow gas exchange between the environment and the interior of the plant
Stroma
- Dense fluid within the chloroplast surrounding the thylakoid membrane
- Contains ribosomes and DNA
- Involved in the synthesis of organic molecules from carbon dioxide and water
Thylakoid
- Flattened membrane sac inside the chloroplast
- Used to convert light energy into chemical energy
Chlorophyll
Green pigment located in membranes within the chloroplasts of plants and algae and in the membranes of certain prokaryotes
Light Reactions
- First of two major stages in photosynthesis
- Comes before the Calvin Cycle
- Occur on the thylakoid membranes of the chloroplast or on membranes of certain prokaryotes
- Convert solar energy into the chemical energy of ATP and NADPH
- Releases oxygen
Calvin Cycle
- Second of two major stages in photosynthesis
- Involves the fixation of atmospheric carbon dioxide and the reduction of fixed carbon into carbohydrate
NADP+
- Nicotinamide adenine dinucleotide phosphate
- Electron acceptor
- As NADPH, temporarily stores energized electrons produced during the light reactions
Photophosphorylation
Process of generating ATP from ADP and phosphate by means of a proton-motive force generated by the thylakoid membrane of the chloroplast during the light reactions of photosynthesis
Carbon Fixation
Initial incorporation of carbon from carbon dioxide into an organic compound by an autotrophic organism (i.e. plant, other photosynthetic organism, chemoautotrophic prokaryote)
Wavelength
DIstance between crests of waves, such as those of the electromagnetic spectrum
Electromagnetic Spectrum
- Entire spectrum of electromagnetic radiation
- Ranges in wavelength from less than a nanometer to more than a kilometer