- Plants remove oxygen as a waste product during photosynthesis and get rid of excess water through transpiration.
- Some wastes are stored in vacuoles, old leaves, or shed parts like leaves and bark.
- Plants also store waste as resins and gums in old xylem or release waste into the soil through roots.
Topics
Chemical Reactions and Equations
- Chemical Reactions in Daily Life
- Chemical Equations
- Balancing Chemical Equation
- Types of Chemical Reactions > Combination Reaction
- Types of Chemical Reactions > Decomposition Reaction
- Types of Chemical Reactions > Single Displacement Reaction
- Types of Chemical Reactions > Double Displacement Reaction
- Chemical Properties of Carbon Compounds > Oxidation
- The Effects of Oxidation Reactions in Everyday Life
Acids, Bases and Salts
- Acids and Bases in Daily Life
- Acids and Bases in the Laboratory
- Acids and Bases React with Metals
- Reaction of Metal Carbonates with Acids
- Acids and Bases Reaction with each other
- Reaction of Metallic Oxides with Acids
- Reaction of a Non-metallic Oxide with Base
- Common Properties of Acids and Bases
- The pH Scale
- Importance of pH in Everyday Life
- Salts > Family of Salts
- Salts > pH of Salts
- Salts > Chemicals from Common Salt
- Salts > Water in Salt Crystals
Metals and Non-metals
Carbon and its Compounds
- Importance of Carbon
- The Covalent Bond
- Allotropes of Carbon > Diamond
- Allotropes of Carbon > Graphite
- Allotropes of Carbon > Fullerene
- Carbon: A Versatile Element
- Organic Compounds
- Classification of Hydrocarbons
- Carbon Compounds: Chains, Branches, Rings
- Homologous Series
- Nomenclature
- Chemical Properties of Carbon Compounds > Combustion
- Ethanol
- Ethanoic Acid
- Soaps and Detergents
Life Processes
- Life Processes in Living Organisms
- Nutrition
- Autotrophic Nutrition
- Heterotrophic Nutrition
- Nutrition in Human Beings
- Dental Caries
- Cellular Respiration
- Human Respiratory System
- Production of ATP
- Blood Circulatory System
- Human Heart
- Blood Vessels Entering and Leaving The Heart
- Valves of the Heart
- Blood Pressure (B.P.)
- Blood Vessels
- Composition of Blood > Cellular Elements: Blood Platelets (Thrombocytes)
- Tissue Fluid (Or Intercellular Fluid)
- Lymph and Lymphatic System
- Transportation in Plants
- Transportation of Water
- Transportation of Food and Other Substances
- Excretion
- Excretion in Human Beings
- Kidney and Its Internal Structure
- Structure of a Kidney Tubule (Nephrons)
- Dialysis and Artificial Kidney
- Excretion in Plants
- Organ and Body Donation
Control and Co-ordination
- Human Nervous System
- Neuron (Or Nerve Cell)
- Synapse
- Nerves
- Reflex Action
- Reflex Arc
- The Human Brain
- The Spinal Cord
- Mechanism of Muscle Action Under Nervous Control
- Coordination and Response to Stimuli in Plants
- Tropic Movements in Plants
- Phototropism
- Geotropism
- Hydrotropism
- Thigmotropism
- Chemotropism
- Hormonal Regulation in Animals
How do Organisms Reproduce?
Heredity
Light – Reflection and Refraction
- Light and Its Straight-Line Propagation
- Reflection of Light
- Spherical Mirrors
- Image Formation by Spherical Mirrors
- Representation of Images Formed by Spherical Mirrors
- Image Formation by Concave Mirror
- Image Formation by a Convex Mirror
- Sign Convention for Reflection by Spherical Mirrors
- Ray Optics - Mirror Formula
- Refraction of Light
- Refraction through a Rectangular Glass Slab
- The Refractive Index
- Refraction by Spherical Lenses
- Image Formation by Lenses
- Image Formation in Lenses Using Ray Diagrams
- Sign Convention for Spherical Lenses
- Lens Formula
- Power of a Lens
The Human Eye and the Colourful World
- The Human Eye
- Defects of Vision and Their Correction
- Defects of Vision and Their Corrections > Myopia
- Defects of Vision and Their Corrections > Hypermetropia
- Defects of Vision and Their Corrections > Presbyopia
- Refraction of Light Through a Prism
- Dispersion of Light
- Atmosphere Refraction
- Scattering of Light
Electricity
Magnetic Effects of Electric Current
- Magnetic Effect of Electric Current
- Applications of Biot-Savart's Law > Magnetic Field due to a Finite Straight Current-Carrying Wire
- Magnetic Field Due to a Current-Carrying Conductor
- Right-hand Thumb Rule
- Applications of Biot-Savart's Law > Magnetic Field at the Centre of a Circular Loop
- Applications of Ampere’s Circuital Law > Magnetic Field of a Long Straight Solenoid
- Force on a Current Carrying Conductor in a Magnetic Field
- Fleming’s Left Hand Rule
- Magnetism in Medicine
- Domestic Electric Circuits
Our Environment
- Introduction
- Excretory Products in Plants
- Key Points: Excretion in Plants
Maharashtra State Board: Class 9
Introduction:
Excretion is the process by which living organisms remove toxic and waste products generated through metabolic activities. While animals have specialised systems for excretion, plants lack such systems. Instead, they use simpler mechanisms to eliminate their waste. Most of the waste substances of plants are stored in vacuoles of leaf cells and in flowers, fruits, and the bark of the stem. After some time, these parts fall off. Some other waste materials are stored in old and worn xylem in the form of resin and gum. Some waste materials are also given out through roots into the surrounding soil.

Leaf fall
Examples of Plant Waste:
- Oils: Found in orange, eucalyptus, and jasmine plants.
- Latex: From rubber and papaya trees.
- Gums: From acacia trees.

Gum and latex
Maharashtra State Board: Class 9
Excretory Products in Plants:
- Gaseous Wastes: Plants produce oxygen during photosynthesis and carbon dioxide during respiration. These gases are released through stomatal pores on leaves. Oxygen is used for respiration, while carbon dioxide is reused in photosynthesis.
- Water: Excess water is released through transpiration, which occurs via stomata, lenticels, and surfaces of stems and fruits.
- Organic By-Products: Plants also produce organic wastes such as gums, resins, oils, and latex during metabolic activities. These are stored in parts like bark, stems, and leaves. Over time, plants shed these parts, removing the stored waste.
- Aquatic Plants: Aquatic plants excrete waste directly into the surrounding water through diffusion. Terrestrial plants can excrete some waste into the soil.
CBSE: Class 10
