Class 7 Science – Chapter 1: Nutrition in Plants

Vocabulary flashcards covering key terms and definitions from Class 7 Science Chapter 1 – Nutrition in Plants.

Nutrition

The process of taking in food by an organism and using it for growth, energy and body maintenance.

Nutrients

Components of food—carbohydrates, proteins, fats, vitamins and minerals—essential for the body.

Autotrophs

Organisms (e.g., green plants) that make their own food from simple substances through photosynthesis.

Autotrophic Nutrition

Mode of nutrition in which an organism manufactures its own food using CO₂, H₂O and sunlight.

Heterotrophs

Organisms (e.g., humans, animals) that cannot make their own food and depend on plants or other organisms.

Heterotrophic Nutrition

Mode of nutrition in which an organism obtains ready-made food from other living things.

Photosynthesis

Process by which green plants synthesize food (glucose) from carbon dioxide and water in presence of sunlight and chlorophyll, releasing oxygen.

Chlorophyll

Green pigment in leaves that captures solar energy for photosynthesis.

Stomata

Tiny pores on leaf surfaces through which plants take in CO₂ and release O₂.

Vessels (xylem)

Tube-like structures that transport water and minerals from roots to leaves.

Leaf – Food Factory

Site where most photosynthesis occurs, making it the primary food-producing organ of a plant.

Glucose

Simple carbohydrate produced in photosynthesis; later converted to starch for storage.

Starch

Storage form of carbohydrate in plants; its presence indicates photosynthesis has occurred.

Sun – Ultimate Energy Source

All life relies on solar energy captured by plants during photosynthesis.

Cell

Basic structural and functional unit of all living organisms.

Cell Membrane

Thin outer boundary of a cell that controls movement of substances in and out.

Nucleus

Centrally located spherical structure in a cell containing genetic material and controlling activities.

Cytoplasm

Jelly-like substance surrounding the nucleus where many cellular processes occur.

Carbohydrates

Energy-providing nutrients composed of carbon, hydrogen and oxygen; include glucose and starch.

Proteins

Nitrogen-containing nutrients synthesized by plants from amino acids; essential for growth and repair.

Fats (Oils)

Energy-rich nutrients that some plants store in seeds (e.g., sunflower) instead of starch.

Parasitic Plant

Non-green plant that obtains food from a host organism; e.g., Cuscuta (amarbel).

Host

Living organism from which a parasite draws food and shelter.

Cuscuta (Amarbel)

Common parasitic plant that uses sucking roots to absorb nutrients from its host.

Insectivorous (Carnivorous) Plant

Green plant that traps and digests insects to obtain nitrogen; e.g., pitcher plant.

Pitcher Plant

Insectivorous plant whose modified leaf forms a pitcher with a lid and hairs to trap insects.

Saprotrophic Nutrition

Mode of nutrition in which organisms obtain nutrients from dead and decaying matter.

Saprotrophs

Plants or fungi (e.g., mushrooms, bread mould, yeast) that feed on decaying organic material.

Symbiosis

Close association between two different organisms in which both may benefit by sharing nutrients and shelter.

Lichen

Symbiotic partnership of an alga and a fungus; fungus provides water and minerals, alga supplies food.

Rhizobium

Nitrogen-fixing bacteria living in root nodules of leguminous plants, converting atmospheric nitrogen into usable compounds.

Leguminous Plants

Plants such as peas and beans that house Rhizobium bacteria and enrich soil nitrogen content.

Replenishment of Soil Nutrients

Process where nitrogen-fixing bacteria restore nitrogen to soil, reducing need for artificial fertilisers.