Photosynthesis & Cellular
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?
What is the equation for the chemical
reaction of photosynthesis?
Six molecules of carbon dioxide react with
six molecules of water to form 1 molecule of
glucose and six molecules of oxygen.
Describe Photosynthesis
The process of changing light energy to
chemical energy
Energy stored as sugar
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
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
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.
Photosynthesis in Action
Let's Look a Photosynthesis in Action
Learn more about
photosynthesis at:
http://www.ftexploring.com/me/photosyn1.html
What is Cellular Respiration?
The release of chemical energy for use by animal or
plant cells to create Biomass (tissue) for growth.
How Does Cellular Respiration
Work?
Once the energy that was in sunlight is changed
into chemical energy (sugar) 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
The breakdown of glucose molecules to release
energy
Takes place in all living things
Is a step by step process
What is the chemical equation for
cellular respiration?
+energy
Cellular Respiration in Action
An analogy can be drawn between the process
of cellular respiration in our cells and a car. The
mitochondria are the engines of our cells where
sugar is burned for fuel and the exhaust is CO2
and H2O. Note that in a car that burned fuel
perfectly, the only exhaust should theoretically
be CO2 and H2O also.
There are three steps in the process of cellular
respiration: glycolysis, the Krebs cycle, and
the electron transport chain.
So why is Photosynthesis and Cellular
Respiration important to me?
Plants play the most important part in the cycle of nature. Without plants,
there could be no life on Earth. They are the primary producers that sustain all
other life forms. This is so because plants are the only organisms that can make
their own food. Animals, incapable of making their own food, depend directly or
indirectly on plants for their supply of food. All animals and the foods they eat
can be traced back to plants.
The oxygen we breathe comes from plants. Through photosynthesis, plants
take energy from the sun, carbon dioxide from the air, and water and minerals
from the soil. They then give off water and oxygen. Animals and other nonproducers take part in this cycle through respiration. Respiration is the process
where oxygen is used by organisms to release energy from food, and carbon
dioxide is given off. The cycles of photosynthesis and respiration help maintain
the earth's natural balance of oxygen, carbon dioxide, and water.
Read how photosynthesis &
Respiration are related:
http://www.usoe.k12.ut.us/curr/science/sciber00/8th/e
nergy/sciber/photosyn.htm