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Nutrition in PlantsCLASS IV
Nutrition in Plants The components of food which are
necessary for our body are called nutrients
All living organisms require food.
Only green plants can make their food themselves. All other plants and animals including human beings are dependent on plants for their food.
Modes of Nutrition in PlantsPLANTS
AUTOTROPHIC HETEROTROPHIC
PARASITIC SAPROTROPHIC
SYMBIOTIC
INSECTIVOROUS PLANTS
Autotrophic Mode of Nutrition
Green plants can make their own food with the help of Carbon dioxide, Water, Sunlight and Chlorophyll. The process is called PHOTOSYNTHESIS.
Leaves are the food factories of plants. Water and minerals present in the soil are absorbed by the roots and transported to the leaves.
CO2 from air is taken through the tiny pores present on the surface of leaves. They are called STOMATA. Stomata is surrounded by “Guard cells”.
The leaves have a green pigment called Chlorophyll. It helps leaves to capture the energy of the Sunlight. The energy is used to synthesize food.
So, we can say that SUN is the ultimate source of energy for all living things.
The leaves other than green also have chlorophyll. The large amount of red, brown and other pigments mask the green colour.
STOMATA
STOMATA
STOMATA
Heterotrophic Mode of Nutrition1.PARASITIC PLANTS The mode of nutrition where an organism
absorb food from other growing green plant (called the host) is called Parasitic.
Parasitic plants develop special roots called HAUSTORIA which penetrate into the tissues of the host plant.
e.g. CUSCUTA (DODDER), MISTLETOES and APODANTHES.
Parasitic plants do cause harm to the host plant.
MISTLETOES
MISTLETOES
CASCUTA
INSECTIVOROUS PLANTS
They are the plants that derive some or most of its nutrients by trapping and consuming animals, mainly insects.
e.g. PITCHER PLANT
PITCHER PLANT The pitcher like structure is the
modified part of the leaf. The apex of the leaf forms a lid which can open and close the mouth of the pitcher.
Inside the pitcher there are hair which are directed downwards. When an insects land in the pitcher, the lid closes and the trapped insect gets entangled into the hair. The insect is digested by the digestive juices secreted in the pitcher.
Tropical Pitcher Plant
Western Australian Pitcher Plant
PITCHER PLANT
Sun Pitcher
Traps work in a variety of ways.Pitfall traps of pitcher plants are leaves folded
into deep, slippery pools filled with digestive enzymes.
Flypaper (or sticky or adhesive traps) of sundews and butterworts are leaves covered in stalked glands that exude sticky mucilage.
Snap traps (or steel traps) of the Venus flytrap and waterwheel plant are hinged leaves that snap shut when trigger hairs are touched.
Suction traps, unique to bladderworts, are highly modified leaves in the shape of a bladder with a hinged door lined with trigger hairs.
Lobster-pot traps of corkscrew plants are twisted tubular channels lined with hairs and glands.
VENUS FLY TRAP
The trap of the Venus fly trap is highly modified leaf. On the inner surface, there are short, stiff hair called trigger or sensitive hair. When anything touches these hair enough to bend them, the two lobes of the leaves snap shut in less than a second.
Venus Flytrap
SAPROTROPHS
In this mode of nutrition, organism take in nutrients in the solution form from dead and decaying matter.
e.g. Mushroom, Bread moulds, Indian Pipe.
symbiotic relationship
Some plants live with other plants and share their food resources. Both the types mutually gain from each other. Such a relation is called Symbiotic.
LICHENS are an association between a fungus and a green algea.
The fungus obtains nutrients from the algea, and the fungal tissue in turn provides shelter for the algea, allowing it to grow in harsh conditions such as rock surfaces where it would otherwise be destroyed.
LICHENS
LICHENS
LICHENS
LICHENS
Certain plants such as peas have a Symbiotic association with bacteria such as Rhizobium. Rhizobium coverts atmospheric nitrogen into plant usable forms e.g. ammonia. The plant in turn provide nutrients for the bacterium growth.
RHIZOBIUM
RHIZOBIUM
RHIZOBIUM
