MODULE 4 - ECOSYSTEM: LIFE

ENERGY

JANET BRIGIDA A. CATIPON

MAE-CHEMISTRY, SST II-MHS

WHAT’S ALL ABOUT?

THE CYCLE : WHY ORGANISMS NEED EACH OTHER?

THE PRODUCER AND ITS ROLE IN THE ECOSYSTEM

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!

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)

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)

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.

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

WHAT ARE THE STRUCTURES INVOLVED IN THE FOOD MAKING

PROCESS OF PLANTS

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?

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?

WHAT’S HAPPENING DURING THE PHOTOSYNTHESIS PROCESS?

INVESTIGATING THE LEAF STOMATA

PARTS OF THE STOMA (SINGULAR)

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!

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.