CBSE Class 7 Science Forests: Our Lifeline Worksheets with Answers - Chapter 17 - PDF

This chapter highlights the state of our country's woods, their importance, and the consequences of their depletion on the environment and people.

Short Notes on CBSE Class 7 Science  - Forests: Our Lifeline:

What Exactly is a Forest?

A forest is an area or a section of land that is densely forested and home to a diverse range of flora. Not only that, but forests are part of a larger ecosystem that includes trees, bushes, plants, microbes, wild animals, and birds. Non-living or abiotic components such as sunshine, air, nutrients, water, and rocks are also included.

What Exactly are a Crown and Canopy?

The crown of a tree refers to the topmost portion or top of the tree. Different trees grow tall together in the forest, and their branches appear like the woodland's ceiling because no sky is visible through these trees. This is known as Canopy.

Stratification in Forests: 

Stratification is the division of a natural ecosystem into various strata based on the heights of the plants or vegetation present. This reduces competition among animals and makes it easier for them to survive. Climate, temperature, light availability, soil type, and rainfall all influence the number of strata found in a forest. A forest's trees are classified into the following divisions in general: The Forest Floor, the Herb Layer, the Shrub Layer, the Understory, the Canopy, and the Emergent Layer are the several layers that make up the forest.

Forests - Dynamic Living Entity:

Forests are dynamic living entities in which all organisms, whether plants or animals, rely on and assist one another in order to exist. Plants are the only source of sustenance for herbivores. Carnivores rely on herbivores for survival. The decomposition of dead animals, plants, and their excreta allows more plants to thrive by providing them with appropriate nutrients. The decomposers help plants flourish by decomposing dead debris in the forest. As a result, forests are known as Dynamic Living Entities.

Importance of Forests:

Forests are important because they provide a natural habitat for a diverse range of animals and plants. They aid in the regulation of oxygen and carbon dioxide levels in the atmosphere. They help to prevent global warming by keeping the air pure by absorbing all of the CO₂. They control the earth's water cycle. They mitigate pollution of the air, water, land, and noise in some way.

They are a rich supply of various human-made products, including fruits and vegetables are a good source of vitamins and minerals. Wood, raw materials for various industries such as paper, wood, and so on, medical items, latex, gum, and resins, honey, and wax, spices, oils, and bones and fur.

How Can Woods Help To Maintain the Water Cycle?

We know that plants use the process of transpiration to get rid of surplus water. Water vapour is emitted into the atmosphere as a result of this process. As a result, trees increase the amount of water vapour in the atmosphere. This water vapour condenses into clouds, causing more rain to fall in the vicinity. This rainwater seeps into the ground, raising the level of subsurface water. As a result, forests help to maintain the water cycle.

Tips for Excelling in Exams:

• Seek Assistance From Your Teacher. If you're still perplexed by the matter, seek clarification. Look up your teacher's open office hours and make an appointment to see them. Bring a few questions regarding the issue and see if they can answer them.

• As Soon as You Learn About the Exam, Begin Studying. Early on, get a head start so you don't have to cram later. While it may be tempting to leave your study till the last minute, you will not remember as much when the exam time comes.

• Examine Your Notes on the Same Day That You Took Them. When you take notes while they're still fresh in your mind, you'll recall them better. Read through your notes again within 3–4 hours after taking them so you may review what your teacher covered.

• Remove Any Potential Sources of Distraction. Turn off your electronics so you can focus on your work. Wait till you've finished your studies to check your notifications, even if it's tempting. To avoid being seduced by social media, set your phone to "Do Not Disturb" mode, turn off the TV, and log out of it.