5.6 Photosynthesis Flashcards
What type of nutrition is photosynthesis known as?
autotrophic nutrition
What are plants that photosynthesize known as?
photoautotrophs
What is it called when carbon dioxide is converted into sugars?
carbon fixation
Why is carbon fixation endothermic?
requires energy and additional electrons
What does respiration do in plants?
oxidize organic molecules to release chemical energy
Why is respiration exothermic?
releases chemical energy
What is it called when there is no net gain or loss of carbohydrate?
compensation point
What is the time taken to reach the compensation point called?
compensation period
Do shade plants have a longer or shorter compensation period?
shorter - can get minimal light easier
How long is a chloroplast?
2-10 um
What are the 2 distinct regions of a chloroplast?
stroma and grana
What are the bridges between grana called?
intergranal lamellae
What is each individual part of the grana called?
thylakoid
What is the funnel shaped structure within a thylakoid membrane called?
A photosystem
What are the pigments on the wall of the photosystem called?
Accessory pigments
What primary pigment does photosystem 1 have?
P700
What primary pigment does photosystem 2 have?
P680
What are the 2 pigments within chlorophyll a?
P700 and P680
What wavelgnth does chlorophyll b absorb?
400-500nm, and 640nm
what wavelenght do cartenoids absorb?
400-500nm
what wavelength do xanthophylls absorb?
375-550nm
What is it called when ATP is produced in the presence of light?
photophosphorylation
What happens to water in PS2?
2H2O = 4H+ + 4e- + O2
aka photolysis
what does water do?
- source of protons (hydrogen) used in photophosphorylation
- donates electrons to chlorophyll
- source of a by product of oxygen
- keeps plant turgid
What are the two types photophosphorylation?
non-cyclic (PS1 and PS2 that produces ATP and NADPH)
cyclic (PS1 only producing ATP)
What is an electron carier?
a protein with iron at its core
