Photosynthesis
How do we get our E? FOOD
How does food get E?
- from sunlight during photosynthesis
- E is extracted from food by cellular respiration
photosynthesis = solar E is converted to chemical E stored in
carbohydrate molecules
How does photosynthesis and cellular respiration form a cycle?
- products of one process is used to start the next one
CO2 + H2O → C6H12O6 + O2
C6H12O6 + O2 → CO2 + H2O
- products of photosynthesis (glucose and O2) are the starting
material for cellular respiration
- cellular respiration is opposite of photosynthesis since it uses C
from glucose (C6H12O6) to provide E for other activities
How do plants use sugar?
- plants use sugar to make other organic molecules (proteins, lipids)
by linking C-atoms together
- plants store E in the form of sugar (newly made)
- sugar can be transported to other parts of the plant that do not
photosynthesis (roots)
- plants are autotrophs (make their organic molecules from
inorganic molecules)
Does all the sugar that gets produced by photo. get used immediately?
No, produce more sugar than can be used.
- next day activity
- rapid growth in the spring
- turned into starch for short- and long-term storage
- converted into oils and stored in seeds
1
, Why do plants often serve as food for animals?
- rich organic molecules that store E
- 250,000+ species
- 150 plants are grown for mass consumption
- 3 major ones feed the world (rice, corn, wheat)
What specialized structures do plants have that allow for sunlight to
be captured?
chloroplasts = “green-molded”
- organelle used for photosynthesis
- tiny green organelle found only in eukaryotic cells that
contain chlorophyll
= pigment in plants that absorb light
6 CO2 + 6 H2O → C6H12O6 + 6 O2
(solar E and chlorophyll)
How are plants specialized to photosynthesize?
- leaves are complexly structured to photosynthesize
- occurs inside the chloroplasts
- thylakoid “sac-like” = flat membrane bound sacs found inside
chloroplasts - chlorophyll is found here
- grana = individual thylakoid stacks
- stroma “bed, mattress” = gel-like fluid in chloroplasts that
hold everything in suspension
How do plants absorb solar E?
- photosynthetic pigments absorb photons
- pigments = molecule that absorbs light to reflect color
Two main pigments:
1. chlorophyll = green pigment in plant that is responsible for
absorbing the solar E used in photosynthesis
chlorophyll a chlorophyll b (accessory pigment)
2
How do we get our E? FOOD
How does food get E?
- from sunlight during photosynthesis
- E is extracted from food by cellular respiration
photosynthesis = solar E is converted to chemical E stored in
carbohydrate molecules
How does photosynthesis and cellular respiration form a cycle?
- products of one process is used to start the next one
CO2 + H2O → C6H12O6 + O2
C6H12O6 + O2 → CO2 + H2O
- products of photosynthesis (glucose and O2) are the starting
material for cellular respiration
- cellular respiration is opposite of photosynthesis since it uses C
from glucose (C6H12O6) to provide E for other activities
How do plants use sugar?
- plants use sugar to make other organic molecules (proteins, lipids)
by linking C-atoms together
- plants store E in the form of sugar (newly made)
- sugar can be transported to other parts of the plant that do not
photosynthesis (roots)
- plants are autotrophs (make their organic molecules from
inorganic molecules)
Does all the sugar that gets produced by photo. get used immediately?
No, produce more sugar than can be used.
- next day activity
- rapid growth in the spring
- turned into starch for short- and long-term storage
- converted into oils and stored in seeds
1
, Why do plants often serve as food for animals?
- rich organic molecules that store E
- 250,000+ species
- 150 plants are grown for mass consumption
- 3 major ones feed the world (rice, corn, wheat)
What specialized structures do plants have that allow for sunlight to
be captured?
chloroplasts = “green-molded”
- organelle used for photosynthesis
- tiny green organelle found only in eukaryotic cells that
contain chlorophyll
= pigment in plants that absorb light
6 CO2 + 6 H2O → C6H12O6 + 6 O2
(solar E and chlorophyll)
How are plants specialized to photosynthesize?
- leaves are complexly structured to photosynthesize
- occurs inside the chloroplasts
- thylakoid “sac-like” = flat membrane bound sacs found inside
chloroplasts - chlorophyll is found here
- grana = individual thylakoid stacks
- stroma “bed, mattress” = gel-like fluid in chloroplasts that
hold everything in suspension
How do plants absorb solar E?
- photosynthetic pigments absorb photons
- pigments = molecule that absorbs light to reflect color
Two main pigments:
1. chlorophyll = green pigment in plant that is responsible for
absorbing the solar E used in photosynthesis
chlorophyll a chlorophyll b (accessory pigment)
2
