Photosynthesis Vocabulary
1. Autotrophs are organisms that can make food.
2. Heterotrophs are organisms that cannot make their own food.
3. Cyanobacteria (blue-green bacteria) are bacteria that can carry out photosynthesis.
4. Oxygen is the gas released during photosynthesis.
5. Light reactions are the photosynthetic reactions that convert light energy into
chemical energy.
6. ATP is the high-energy compound that is made in the light reactions of
photosynthesis.
7. NADP is the coenzyme that is reduced in the light reactions.
8. CO2 is the gas needed to carry out the dark reactions of photosynthesis.
9. H2O is the compound that generates H+/- for the light reactions. It also generates
oxygen.
10. Stomata are the openings on the leaf where transpiration and respiration takes place.
11. Guard cells are special cells that regulate the opening and closing of the openings.
12. Transpiration is the process whereby plants lose water through the leaves.
13. Vascular tissue refers to the conducting tissue.
14. Xylem is a type of conducting tissue that moves water and minerals in the plant.
15. Phloem is a type of conducting tissue that moves food in the plant.
16. Chloroplasts are organelles that are needed to carry out photosynthesis.
17. Leaf is the major organ of a plant that produces food.
18. Grana consists of thylakoids where the light reactions take place in chloroplasts.
19. Stroma is the region of the chloroplast where the C3 Cycle takes place.
20. Chlorophyll a is the major pigment of photosynthesis.
21. Photosystem consists of a reaction center, antennae complex, and a primary eacceptor that is required in the light reactions.
22. Reaction center is the location of the special chlorophyll a molecules that are oxidized
during the light reactions.
23. Antennae complex is the collection of pigments that helps to absorb light energy at
the reaction centers in each photosystem.
24. Electron transport chain is a series of proteins and lipids that are involved with the
transfer of e- from H2O to NADP during the light reactions and also in the generation
of ATP.
25. Mesophyll is the area of the leaf where most of the photosynthesis takes place.
26. Photolysis refers to H2O splitting releasing 2H+, 2e-, and ½ O2.
27. Ribulose BiPhosphate is the 5 carbon compound required to start the dark reactions.
28. PGAL (glyceraldehydes 3 phosphate) is the main produce (triose) of the dark
reactions.
29. Sucrose is the carbohydrate transported around in the vascular tissue of plants.
30. Anabolism refers to metabolic reactions that involves the synthesis of molecules.
31. Catabolism refers to metabolic reactions that involve the degradation of molecules.
32. Bundle Sheath Cells are special cells that surround the vascular tissue.
33. Cellulose is the major polysaccharide in plant cell walls.
34. Oxidation-Reduction are reactions that involves the loss and gain of electrons.
35. Chemiosmosis is the process by which ATP is synthesized when H+ diffuses down
the hydrophilic channel of ATP Synthase.
36. RuBP Carboxylase is the major enzyme that fixes CO2 into a carbohydrate in the C3
cycle of photosynthesis.
37. Xanthophyll is the yellow pigment (carotenoids).
38. Carotene is an orange pigment (carotenoids).
39. Oxygen is the gas that would inhibit the rate of photosynthesis.
40. Turgor pressure that builds up in guards cells to open the stomates.
41. Potassiums K+ is a cation tha tlowers the H2O potential in guard cells.
42. Source to sink describes the movement of sucrose in a plant from where it is made to
where it ends up.
43. Starch is the storage polysaccharide in plants.
44. Dark Reactions are reactions of photosynthesis that are light independent.
45. ATP Synthase Complex is the enzyme that makes ATP.
46. Photophosphorylation is the process in photosynthesis whereby ATP is made as the
result of light energy.
47. Circadian Rhythm refers to an internal 24-hour clock.
48. Visible light is the range in the electromagnetic spectrum that is used by plants for
photosynthesis.
49. Cycle Electron Flow is the part of the light reactions that involves only Photosystem I
and generates only ATP.
50. Non-Cyclic Electron Flow is part of the light reactions that involves photosystems I
and II and both ATP and NADPH are made.
51. Thylakoids are disk-shaped structures making up the grana where photosystems, etransport chains and ATP synthases are concentrated.
52. Photorespiration is a process that uses oxygen, generates carbon dioxide in the
mitochondria, and siphons off “C” sources in C3 plants.
53. PEP Carboxylase is the enzyme use to combine CO2 with PEP to form OAA in C4
plants.
54. C4 plants refer to plants that carry out the C3 cycle in the bundle sheath cells instead
of the mesophyll cells.
55. CAM refers to plants that normally close their stomates during the day and open them
at night to take on CO2.
56. Greenhouse effect is the direct result of an increase in CO2 in the atmosphere.
57. Photosynthesis is the process whereby autotrophs use a light energy source and an
inorganic carbon source (CO2) to make food and release O2.
58. Roots are plant organs that anchor the plant into the ground and function also to
absorb H2O and minerals.
59. Oxidative phosphorylation is a type of phosphorylation that occurs during cellular
respiration in which ATP is made by the catabolism of food by using O2.
60. Adenine is the nitrogenous base found in ATP.
61. Chromatography paper is the paper used to separate pigments by using an organic
solvent.
62. Pigments refers to a substance that absorbs and reflects light energy.
63. Glycolic Acic/Glycolate is the 2 carbon compound formed during photorespiration
when the unstable 5 C compound splits.
64. Calvin Cycle is another name for the C3 Cycle or the dark reactions of
photosynthesis.
65. 3.5 billion years refers to the number of years that photosynthesis has been evident in
fossil rock.