Questions & Answers
521 answers across all subjects
What is spinning?
Spinning is the process of making yarn from fibres. During spinning, fibres such as cotton, wool, or silk are drawn out and twisted together to form a continuous thread called yarn. The twisting of fibres helps them hold together firmly and increases the strength of the yarn. Spinning can be done using traditional tools such as the spindle and charkha, or with modern spinning machines used in textile factories. Once the yarn is produced, it can be used to make fabrics through weaving or knitting.
Where and when is jute cultivated?
Jute is mainly cultivated in alluvial soils found in the delta regions of large rivers such as the Ganga and Brahmaputra. These regions have fertile soil and plenty of water, which are suitable conditions for growing jute plants. In India, jute is mainly grown in states such as West Bengal, Bihar, and Assam. Jute is usually cultivated during the rainy season, as it requires warm and humid climate with adequate rainfall for proper growth.
Mention two uses of nylon and two uses of coconut fibres.
Uses of nylon: Making ropes Making fishing nets Nylon is strong, flexible, and resistant to water, which makes it suitable for these uses. Uses of coconut fibres: Making doormats Making ropes Coconut fibres are strong and rough, making them useful for household and industrial products.
Why are coconut fibres used for making ropes?
Coconut fibres, also called coir fibres, are obtained from the outer covering or husk of coconut. These fibres are very strong, rough, and durable. Because of their strength and toughness, coconut fibres are suitable for making items that require strong material. They are widely used for making ropes, mats, brushes, and doormats. Their rough texture makes them less suitable for making clothes but ideal for products that require durability and strength.
Which parts of plants give us cotton and jute?
Different plant fibres are obtained from different parts of plants. Cotton fibres are obtained from the cotton bolls, which grow around the seeds of the cotton plant. When the cotton fruit ripens, it bursts open and the soft cotton fibres become visible. Jute fibres are obtained from the stem of the jute plant. The stem contains long, strong fibres that are separated and processed to make products such as ropes, sacks, and carpets.
What is weaving?
Weaving is the process of arranging two sets of yarns together to form a fabric. One set of yarns runs lengthwise, while the other set runs crosswise. These yarns are interlaced with each other in a particular pattern to produce cloth. Weaving is done on machines called looms. Looms may be hand-operated or power-operated. Handlooms are traditionally used by skilled weavers, while power looms use electricity and machines to produce large quantities of fabric quickly. Weaving is one of the oldest methods of making cloth and is widely used in the textile industry to produce fabrics such as cotton cloth, silk cloth, and woollen fabrics.
How are fabrics made from yarn?
Fabrics are made from yarn through different processes. The two main methods are weaving and knitting. In the weaving process, two sets of yarns are arranged together in a particular pattern to form a fabric. In knitting, a single yarn is used to make loops that are interlocked with each other to create fabric. These processes convert yarn into different types of cloth used for making garments, bedsheets, curtains, and other textile products. The type of fabric produced depends on the method used and the type of yarn.
What is ginning?
Ginning is the process of separating cotton fibres from the cotton seeds. After cotton is harvested from the cotton plant, the fibres are still attached to the seeds. These seeds must be removed before the fibres can be used to make yarn and fabric. In earlier times, ginning was done by hand, where workers separated the seeds from the cotton fibres manually. Today, machines called ginning machines are used to perform this process more quickly and efficiently. Once the seeds are removed, the clean cotton fibres are collected and compressed into bales. These bales are then sent to textile factories where the fibres are processed further to produce yarn and fabric.
. What are synthetic fibres?
Synthetic fibres are man-made fibres produced from chemical substances in factories. Unlike natural fibres, they are not obtained from plants or animals. Scientists develop synthetic fibres using chemical processes to produce fibres with special qualities such as strength, elasticity, and durability. Examples of synthetic fibres include nylon, rayon, polyester, and acrylic. These fibres are widely used in the textile industry because they are strong, lightweight, and easy to maintain. Clothes made from synthetic fibres dry quickly, resist wrinkles, and are often cheaper than natural fibres. Synthetic fibres are used for making clothes, ropes, fishing nets, parachutes, carpets, and many other products. However, unlike natural fibres, most synthetic fibres are not biodegradable, which means they do not decompose easily in nature and may cause environmental pollution.
What are natural fibres?
Natural fibres are fibres that are obtained from plants or animals and are used to make yarn and fabrics. These fibres occur naturally in nature and are not made by humans in factories. Natural fibres have been used by humans since ancient times to make clothes, ropes, carpets, and other useful items. Plant fibres are obtained from different parts of plants. For example, cotton is obtained from the cotton plant, jute is obtained from the stem of the jute plant, and coir (coconut fibre) is obtained from the husk of coconut. These plant fibres are widely used to make cloth, ropes, mats, and bags. Animal fibres are obtained from animals. Wool is obtained from the hair of sheep and some other animals, while silk is obtained from the cocoon of silkworms. Animal fibres are usually soft and warm, which makes them suitable for making winter clothes. Natural fibres are comfortable to wear, biodegradable, and environmentally friendly. Some common examples of natural fibres are cotton, jute, wool, silk, and coir.
Name the organ used by: (a) Fish during swimming (b) Earthworms during moving
(a) Fish use their muscular tail and fins for swimming. (b) Earthworms move by contracting and expanding their body muscles, helping them crawl forward.
Give one location for each of the following in our body. (i) Hinge joint (ii) Gliding joint
(i) A hinge joint is found in the knee and elbow. (ii) A gliding joint is found between the bones of the backbone.
Describe the skeletal system. Write any two functions of it.
The skeletal system is the framework of bones and cartilage that supports and gives shape to the body. In humans, it consists of 206 bones along with cartilage. It includes parts such as the skull, backbone, ribs, breastbone, arms, legs, shoulder bones, and hip bones. Functions of the skeletal system: It provides structure and shape to the body. It protects delicate internal organs like the brain, heart, and lungs.
How does a fish swim?
A fish swims with the help of its streamlined body, which reduces resistance while moving in water. Its body is shaped like a spindle, allowing it to glide easily. Fish use their muscular tail to push themselves forward, while their fins help in balancing and changing direction. The coordinated movement of tail and fins enables smooth swimming.
What is a backbone?
The backbone, also known as the vertebral column, is a long structure that extends from the skull to the hip. It is made up of 33 small bones called vertebrae, which are joined together in a chain-like manner. The backbone supports the body, helps us stand upright, and protects the spinal cord, which is an important part of the nervous system.
What are joints? Name them.
Joints are the places in the body where two or more bones meet. They allow movement and flexibility. At the joints, bones are held together by strong tissues called ligaments. There are different types of joints in the human body, including: Fixed joints (do not allow movement, e.g., skull) Ball and socket joints (allow movement in all directions) Hinge joints (allow movement in one direction, like knees and elbows) Pivotal joints (allow rotation, like neck) Gliding joints (allow bones to slide over each other)
Define cartilage. Where is it found in the body?
Cartilage is a soft and flexible connective tissue that is not as hard as bone. It can be bent easily without breaking. Cartilage is present in various parts of the body such as the joints, where it helps reduce friction between bones, and in the ear, where it provides shape and support. It is also found in the nose and other parts of the body.
Describe the snail.
A snail is a small, soft-bodied animal that has a hard outer shell covering its body. This shell protects the snail from danger but does not help in its movement. The snail can come out of an opening in the shell when needed. It moves using a muscular structure called the foot, which is located on the underside of its body (belly). The snail moves very slowly in a wavy motion by contracting and relaxing its muscles.
What is an organ?
An organ is a group of different tissues that work together to perform a specific function in the body. Each organ has a particular role. For example, the stomach helps in digestion of food, and the heart pumps blood throughout the body. Several organs working together form an organ system, such as the digestive system or circulatory system.
Which of the skull bones is movable?
The lower jaw, also known as the mandible, is the only movable bone in the skull. This movable bone allows us to open and close our mouth. Because of this movement, we can chew food, speak, laugh, and sing. All other bones in the skull are fixed and joined together to protect the brain.