CHAPTER 13 : PHOTOSYNTHESIS 🪴☀️
PHOTOSYNTHESIS
DEFINITION
-a process used by plants and other organisms to convert light into chemical and
released to fuel the organism's activities
STAGES
1) LIGHT DEPENDENT STAGE (sunlight needed)
-water broken down into hydrogen and oxygen using energy
2)LIGHT INDEPENDENT STAGE
-hydrogen reacts with co2 to form a carbohydrates
LIGHT
-photons oscillate along a path measured as wavelength, contain in electromagnetic
spectrum (visible light)
-plants have pigment that facilitate the capture of wavelengths of light
-color of pigment comes from the wavelengths of light reflected (green bc reflect
yellow and green wavelengths of light)
CHLOROPLAST
-site of photosynthesis
STRUCTURE
1)Double membrane with phospholipid inner and outer membrane and
intermembrane space
2)Contain aqueous fluid called stroma where the light independent reactions / Calvin
cycle take place. It contains enzymes of the Calvin cycle, sugars and organic acids.
3)Stroma contains stacks (grana) of thylakoids which is the site of photosynthesis
, 4)Grana consists of a stack of thylakoids to increase surface area for photosystems
for the absorption of light energy. It is also used for many ETC and ATP synthase for
light dependent stages.
5)Stromas contain organelles such as 70s ribosomes, circular DNA, lipids and
starch grain
PHOTOSYSTEM
-light absorbing unit of the chloroplast
-found in the thylakoid membranes of the chloroplast consists of antenna complex
and reaction center
Chlorophyll - absorbed photons of light
TYPES : Photosystem 1 and 2
STAGES OF PHOTOSYNTHESIS
1)LIGHT DEPENDENT STAGE
-occurs on the thylakoids membranes of the chloroplast
-light energy is required
-light energy and water are used to create ATP and reduced NADP which are needed
for the light independent stage
1. NON-CYCLIC PHOTOPHOSPHORYLATION (‘Z’ scheme)
-involves both photosystems
-key points : high energy electrons, photolysis, photophosphorylation, electron
acceptors (protein), electron transport chain, NADP , photosystems (PSII & PS1)
PHOTOSYNTHESIS
DEFINITION
-a process used by plants and other organisms to convert light into chemical and
released to fuel the organism's activities
STAGES
1) LIGHT DEPENDENT STAGE (sunlight needed)
-water broken down into hydrogen and oxygen using energy
2)LIGHT INDEPENDENT STAGE
-hydrogen reacts with co2 to form a carbohydrates
LIGHT
-photons oscillate along a path measured as wavelength, contain in electromagnetic
spectrum (visible light)
-plants have pigment that facilitate the capture of wavelengths of light
-color of pigment comes from the wavelengths of light reflected (green bc reflect
yellow and green wavelengths of light)
CHLOROPLAST
-site of photosynthesis
STRUCTURE
1)Double membrane with phospholipid inner and outer membrane and
intermembrane space
2)Contain aqueous fluid called stroma where the light independent reactions / Calvin
cycle take place. It contains enzymes of the Calvin cycle, sugars and organic acids.
3)Stroma contains stacks (grana) of thylakoids which is the site of photosynthesis
, 4)Grana consists of a stack of thylakoids to increase surface area for photosystems
for the absorption of light energy. It is also used for many ETC and ATP synthase for
light dependent stages.
5)Stromas contain organelles such as 70s ribosomes, circular DNA, lipids and
starch grain
PHOTOSYSTEM
-light absorbing unit of the chloroplast
-found in the thylakoid membranes of the chloroplast consists of antenna complex
and reaction center
Chlorophyll - absorbed photons of light
TYPES : Photosystem 1 and 2
STAGES OF PHOTOSYNTHESIS
1)LIGHT DEPENDENT STAGE
-occurs on the thylakoids membranes of the chloroplast
-light energy is required
-light energy and water are used to create ATP and reduced NADP which are needed
for the light independent stage
1. NON-CYCLIC PHOTOPHOSPHORYLATION (‘Z’ scheme)
-involves both photosystems
-key points : high energy electrons, photolysis, photophosphorylation, electron
acceptors (protein), electron transport chain, NADP , photosystems (PSII & PS1)
