Ecosystem, Photosynthesis, Cellular Respiration

1. MODULE 4 - ECOSYSTEM:
LIFE ENERGY
JANET BRIGIDA A. CATIPON
MAE-CHEMISTRY, SST II-MHS

2. WHAT’S ALL ABOUT?

3. THE CYCLE : WHY ORGANISMS NEED EACH
OTHER?

4. THE PRODUCER AND ITS ROLE IN THE
ECOSYSTEM

5. WHY PLANTs ???
Directly from plants: Indirectly from plants:
For example, apples come
from an apple tree. The
flour used to make bread
comes from a wheat plant.
Steak comes from a cow,
and we all know that cows
are animals, not plants,
right? But what does the
cow eat? It eats grass and
grains—PLANTS!
Plants are very important to us. All food people eat comes directly or indirectly from
plants.
So all the foods we eat come from plants. But what do plants eat?
They make their own food!

6. PLANTS MAKING FOOD AND WHAT DO
THEY NEED FOR IT?
Plants need several things to make their own food. They need:
• Chlorophyll, a green pigment found in the leaves of plants (see the layer of
chlorophyll in the cross-section of a leaf below)

7. PLANTS MAKING FOOD AND WHAT DO
THEY NEED FOR IT?
• LIGHT (either natural sunlight or artificial
light, like from a light bulb)
• CARBON DIOXIDE (CO2)(a gas found in the
air; one of the gases people and animals
breathe out when they exhale)
• WATER (which the plant collects through
its roots)
• NUTRIENTS AND MINERALS (which the plant
collects from the soil through its roots)

8. THE PROCESS OF MAKING FOOD OF
PLANTS
Plants make food in their leaves. The
leaves contain a pigment called
chlorophyll, which colors the leaves
green. Chlorophyll can make food the
plant can use from carbon dioxide, water,
nutrients, and energy from sunlight. This
process is called
PHOTOSYNTHESIS.

9. WHAT ARE THE STRUCTURES INVOLVED IN THE FOOD
MAKING PROCESS OF PLANTS

10. WHAT ARE THE STRUCTURES INVOLVED IN THE FOOD
MAKING PROCESS OF PLANTS

11. THERE ARE 2 STAGES OF
PHOTOSYNTHESIS, NAMELY:
1) LIGHT-DEPENDENT REACTION
occurs in the thylakoid
membrane in the chloroplast
and converts light energy to
chemical energy. The water,
one of the raw materials is
utilized during this stage and
facilitates the formation of the
free electrons and oxygen.The
energy harvested during this
stage is stored in the form of
ATP ( Adenine Triphosphate) and
NADPH ( Nicotinamide Adenine
Dinucleotide Phosphate
Hydrogen), which are needed in
the next stage to complete the
photosynthesis process.
WHAT’S HAPPENING DURING THE
PHOTOSYNTHESIS PROCESS?

12. 2) LIGHT-INDEPENDENT REACTION
(The Calvin Cycle) takes place in
the Stroma of Chloroplast and
converts carbon dioxide (CO2) into
sugar. This stage does not directly
need light but needs the products
of light reaction (ATP and NADPH).
WHAT’S HAPPENING DURING THE
PHOTOSYNTHESIS PROCESS?

13. WHAT’S HAPPENING DURING THE
PHOTOSYNTHESIS PROCESS?

14. INVESTIGATING THE LEAF STOMATA

15. PARTS OF THE STOMA (SINGULAR)

16. THE ROLE OF STOMATA
Take a deep breath in and then let it out. Breathing to
you is a very natural function that you usually do without
even thinking about it. When you breathe, you are taking in
oxygen and releasing carbon dioxide. Taking in oxygen is very
important, because it allows your cells to do things like
make energy from the food you eat.
Plants 'breathe' too, but they do it through tiny
openings in leaves called stomata (singular: stoma). Stomata
open and close to allow the intake of carbon dioxide and the
release of oxygen. It's very important that they do this,
because this is the very oxygen that we ourselves need to
breathe!

17. THE ROLE OF STOMATA
The gas exchange that occurs when stomata are open
facilitates photosynthesis. Photosynthesis is the process by which
plants convert sunlight into usable energy. During photosynthesis,
carbon dioxide is taken in from the atmosphere through the
stomata and oxygen is released as a waste product. Both
photosynthesis and the gas exchange that powers it are essential
to the plant's survival.
An unfortunate side effect of the stomata opening is that it
allows for water loss. Unlike you and me, plants do not need to
sweat to cool off and prefer to keep their water inside; however,
because the gas exchange of photosynthesis is so vital, some water
loss through stomata is necessary. This process of plant water loss
is called TRANSPIRATION.