Transcript File - Mrs. V. Murphy`s Science Class

Photosynthesis,
Transpiration & Respiration
What is Photosynthesis?
The process of photosynthesis is a
chemical reaction.
It is the most important chemical reaction
on our planet.
What is the Equation for the
Chemical Reaction of
Photosynthesis?
EQUATION FOR
PHOTOSYNTHESIS
WATER
6CO2 + 6H2O +ENERGY
CARBON
DIOXIDE
OXYGEN
C6H12O6 + 6O2
GLUCOSE
Six molecules of carbon dioxide react with
six molecules of water to form 1 molecule of
glucose and six molecules of oxygen.
Describe Photosynthesis
Describe Photosynthesis
• The process of changing light energy to
chemical energy
• Energy stored as sugar (glucose)
• Occurs in plants and some algae
• Plants need light energy, CO2, and H2O
• Takes place in the chloroplasts, using
chlorophyll, the green pigment in plants
Chloroplast
Chlorophyll
What happens during
photosynthesis?
What happens during
photosynthesis?
• Plants capture light energy and use that
energy to make glucose
• Sunlight provides the energy needed by
chlorophyll to change molecules of carbon
dioxide and water into glucose
• Oxygen is also released in this reaction
What happens during
photosynthesis?
• Carbon dioxide enters the leaf through holes
called stomata
• CO2 combines with the stored energy in the
chloroplasts through a chemical reaction to
make glucose
• The sugar is moved through tubes in the leaf to
the roots, stems and fruits of the plants
• Some of the sugar is used right away by the
plant for energy; some is stored as starch; and
some is built into plant tissue
• Photosynthesis Video Clip
Why is this important to us?
TRANSPIRATION
• The process by which liquid water
changes into water vapor.
• Transpiration is essentially evaporation
of water from plant leaves.
Studies have revealed that about 10
percent of the moisture found in the
atmosphere is released by plants through
transpiration.
l
http://ga.water.usgs.gov/edu/watercycletranspiration.htm
Why is this important to us?
• We cannot make our own food (glucose,
energy), we must get our food from plants.
• Plants are the first step in the food chain.
• The oxygen released during photosynthesis
is necessary for all living things.
Learn more about
photosynthesis at:
http://www.ftexploring.com/me/photosyn1.html
What is Cellular Respiration?
What is Cellular Respiration?
The release of chemical energy for use by
cells.
What is Cellular Respiration?
Once the energy that was in sunlight is
changed into chemical energy by
photosynthesis, an organism has to
transform the chemical energy into a form
that can be used by the organism.
This process is cellular respiration.
Describe Cellular Respiration
Describe Cellular Respiration
• The breakdown of glucose molecules to
release energy
• Takes place in all living things
• Is a step by step process
Cellular Respiration takes
place in the Mitochondria
What is the chemical equation
for cellular respiration?
EQUATION FOR
RESPIRATION
CARBON
DIOXIDE
GLUCOSE
C6H12O6 + 6O2
OXYGEN
ATP
6CO2 + 6H2O + ENERGY
WATER
Cellular Respiration Song
and
• Cellular Respiration Song.htm
Read more about
respiration:
http://www.ftexploring.com/links/respiration.
html
Photosynthesis vs. Cellular
Respiration
Photosynthesis
Cellular Respiration
Occurs in the presence of
Occurs at all times in cells
light (and chlorophyll in plant
cells)
Requires energy (light) to
make glucose (sugar)
Releases energy from
glucose (sugar)
Carbon dioxide and water
are needed.
Carbon dioxide and water
are the waste products.
Oxygen is given out
Oxygen is taken in
Transpiration
• Transpiration is the flow of water through a plant.
• Transpiration is essentially evaporation of water from plant
leaves.
• Studies have revealed that about 10 percent of the
moisture found in the atmosphere is released by plants
through transpiration.
l
http://ga.water.usgs.gov/edu/watercycletranspiration.htm
• An acre of corn gives off about 3,000-4,000 gallons
(11,400-15,100 liters) of water each day, and a large oak
tree can transpire 40,000 gallons (151,000 liters) per year.
http://ga.water.usgs.gov/edu/watercycletranspiration.html
Process for Transpiration
1. Plants absorb water from the soil.
2. The water moves from the roots to the
stems through the xylem vessels to the
leaves.
3. Once the water reaches the leaves, some of
it evaporates from the leaves through the
stoma. Which adds water vapor into the air.
http://www.youtube.com/watch?v=At1BJJDcXh
k
Questions to Consider:
1. Would plants and animals be able to survive if
photosynthesis did not occur? Why or Why not.
2. Would plants and animals be able to survive if
respiration did not occur? Why or Why not.
3. How do the processes of respiration, photosynthesis,
and transpiration allow organisms to survive?