Explore plant nutrition using Mind Maps. Learn how plants produce food through photosynthesis, using chlorophyll, water, and carbon dioxide. Understand nutrition modes like autotrophic, heterotrophic, parasitic, and saprotrophic. See the essential role plants play in supplying energy and oxygen for life.
Modes of Nutrition
- Plants and animals have different ways of obtaining nutrition.
Autotrophic Nutrition
- Some organisms, like plants, can make their own food.
- This is called autotrophic nutrition.
- Organisms that do this are called autotrophs.
- They use simple substances like water, carbon dioxide, and minerals.
- Photosynthesis is the process they use to make food. This process relies on chlorophyll.
Heterotrophic Nutrition
- Other organisms, like animals and humans, cannot make their own food.
- They depend on plants or other animals for food.
- This is called heterotrophic nutrition.
- Organisms that do this are called heterotrophs.
Other Modes of Nutrition in Plants
- Not all plants make their own food. Some have other ways to get nutrients.
Parasitic Plants
- Some plants don’t have chlorophyll.
- They can’t do photosynthesis.
- They live on other plants and take their food.
- These are called parasites.
- The plant they live on is called the host.
- Example: Cuscuta (Amarbel).
Saprotrophic Nutrition
- Some organisms get their food from dead and decaying things.
- This is called saprotrophic nutrition.
- Organisms that do this are called saprotrophs.
- Example: Fungi (mushrooms, molds).
Symbiotic Relationship
- Sometimes, two different organisms live together and help each other.
- This is called a symbiotic relationship.
- Example 1: Rhizobium bacteria live in the roots of some plants (legumes). They fix nitrogen from the air, which plants need. The plants give the bacteria food and shelter.
- Example 2: Lichens are a combination of algae and fungi. The algae make food, and the fungi provide shelter and absorb water and minerals.
Insectivorous Plants
- Some plants can trap and eat insects.
- They are insectivorous.
- They grow in places where the soil doesn’t have enough nutrients, especially nitrogen.
- They trap insects to get the nitrogen they need.
- Example: Pitcher plant, Venus flytrap.
Photosynthesis: The Food Making Process in Plants
- Photosynthesis is how plants make food.
Leaves as Food Factories
- Leaves are where most photosynthesis happens.
- They are like the plant’s food factories.
Raw Materials
- Plants need a few things for photosynthesis:
- Water: Taken up from the soil by roots.
- Carbon dioxide: Taken from the air through tiny holes called stomata.
- Sunlight: Captured by a green pigment called chlorophyll.
Chlorophyll
- Chlorophyll is what makes leaves green.
- It absorbs sunlight.
The Process
- In photosynthesis, sunlight’s energy is used to change carbon dioxide and water into sugar (glucose).
- Oxygen is also made.
Equation
- Carbon dioxide + water + sunlight + chlorophyll → glucose + oxygen
Oxygen Release
- The oxygen we breathe comes from photosynthesis.
Starch as an Indicator
- Plants store glucose as starch.
- If a leaf has starch, it means photosynthesis happened.
Other Green Parts
- Photosynthesis can also happen in other green parts of the plant, like green stems.
Leaves of Different Colors
- Even leaves that aren’t green can do photosynthesis.
- They have chlorophyll, but other colors cover it up.
Importance
- Photosynthesis is very important for life on Earth.
- It’s how plants make food, which animals eat.
- It also makes the oxygen we need to breathe.
- The sun is the main source of energy for everything.
Synthesis of Plant Food Other Than Carbohydrates
- Plants use the sugar they make in photosynthesis to make other things they need.
Proteins
- Proteins are important for growth and repair.
- They contain nitrogen.
- Plants get nitrogen from the soil.
- Some bacteria help plants get nitrogen from the air (nitrogen fixation).
Fats
- Fats store energy.
Saprotrophs
- Saprotrophs get their food from dead and decaying things.
- They break down the dead material and absorb the nutrients.
- Fungi are important saprotrophs.
How Nutrients Are Replenished in the Soil
- Plants take nutrients from the soil.
- Over time, the soil can run out of nutrients.
- Farmers add manure and fertilizers to put nutrients back in the soil.
- These contain things like nitrogen, phosphorus, and potassium, which plants need.
- Crop rotation is another way to keep the soil healthy.
Q&A
Why do organisms take food?
- Organisms need food for energy, growth, and to stay healthy.
Distinguish between a parasite and a saprotroph.
- A parasite lives on or in another living organism (the host) and gets its food from the host, often harming it.
- A saprotroph gets its food from dead and decaying organic matter.
How would you test the presence of starch in leaves?
- You can use iodine solution. If starch is present, the iodine will turn dark blue or black.
Give a brief description of the process of synthesis of food in green plants.
- Green plants make food through photosynthesis. They use sunlight, water, and carbon dioxide (taken in through stomata) to make glucose (sugar) and oxygen. Chlorophyll in leaves captures the sunlight.
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