NCERT Solutions for Class 9th Science Chapter 3 Project work — The Journey Beyond

Book page 47 Updated on2026-09-08

Q1.

Visit a doctor and find out what happens in ligament rupture, cartilage rupture and fracture of bones. How can we reduce the risk by changing our lifestyle and nutritional balance?

Answer

How to do it: carry a written list of questions, note the doctor's answers in your own words, and ask for one example each of an injury they commonly treat in young people. Record the tissue involved, the symptom, the usual treatment and the recovery time.

Sample answer:

Injury	Tissue involved	What happens	Why recovery is slow or fast
Ligament rupture	Ligament — bone to bone	The tough band tears, so the joint loses stability and can move beyond its safe limit; there is pain, swelling and a feeling that the joint gives way	Ligaments have a poor blood supply, so healing is slow; a badly torn one may need surgery
Cartilage rupture	Cartilage — cushion at bone ends and between vertebrae	The soft, jelly-matrix pad tears; the bone ends grind together, causing pain and stiffness on movement	Cartilage has almost no blood supply of its own, so it heals very poorly and damage is often permanent
Fracture of bone	Bone — rigid matrix of calcium and phosphorus compounds	The bone cracks or breaks; severe pain, swelling and inability to bear weight	Bone is richly supplied with blood, so it heals comparatively well once set — usually in 6 to 8 weeks

Reducing the risk:

Nutrition — calcium and phosphorus for the bone matrix (milk, curd, ragi, sesame, green leafy vegetables), vitamin D from sunlight to absorb that calcium, and protein for muscle and for the connective tissue of tendons and ligaments.
Regular exercise — loading a bone makes it lay down more matrix, and strong muscles around a joint take load off the ligaments.
Warm up and stretch before games; most ligament tears happen on a cold, sudden twist.
Correct posture while sitting, studying and lifting; lift with the knees bent, not with a bent back.
Yoga — research shows it improves flexibility, posture and breathing, reduces stress and helps prevent lifestyle diseases. 21 June is observed every year as International Yoga Day.
Proper footwear, safe playing surfaces, and enough rest between hard sessions.

Q2.

Perform the following activity. (i) Sit with your feet flat on the floor. (ii) Place your fingers on the back of your ankle just above the heel (Fig. 3.24). (iii) Point your toes down and up, and you will feel the tendon moving. Tendons are designed to withstand huge pulling forces. Try exploring other tendons in your body around the different joints.

Answer

What you will feel: a thick, firm cord under the skin just above the heel that tightens and slides when you point your toes down, and slackens when you pull them up. That is the tendon joining your calf muscle to the heel bone.

Other tendons you can find on yourself:

Where to press	What to do	Tendon connecting
Back of the ankle, above the heel	Point the toes down and up	Calf muscle → heel bone
Back of the wrist	Straighten and bend the fingers	Forearm muscles → finger bones
Front of the elbow	Bend the elbow against resistance	Biceps → forearm bone
Just below the kneecap	Straighten the knee while seated	Thigh muscle → shin bone
Back of the knee, on either side	Bend the knee	Hamstring muscles → leg bones

Why tendons can take such large forces: a tendon is dense connective tissue whose fibres all run in the same direction — the direction of the pull. Fibres lined up along the line of force share the load evenly, which is exactly how a rope is made strong. The heel tendon in particular has to carry several times your body weight every time you push off to run or jump, so it is the thickest tendon in the body.

Check it yourself: notice that the muscle that moves your fingers is in the forearm, not in the hand. Keeping the bulky muscle far away and transmitting its pull through long tendons is what makes the hand slim enough for fine work — writing, playing an instrument, holding a dance mudra.

Q3.

Reflect on any of the physical practices you are familiar with, such as yoga, kabaddi, etc. How would it support bone and muscle health?

Answer

How to answer: pick one practice you actually do, describe what the body does in it, and then connect each movement to a tissue in this chapter — bone, muscle, tendon, ligament, cartilage.

Sample answer — kabaddi. A kabaddi raid combines sprinting, sudden stops, low crouches, twisting escapes and grappling.

Bone. Running and jumping load the leg bones repeatedly. Bone responds to load by depositing more of its calcium-and-phosphorus matrix, so the bones become denser and stronger.
Muscle. Repeated powerful contraction thickens the skeletal muscle fibres, so the player produces more force and tires less quickly.
Joints and ligaments. Constant changes of direction train the ligaments and the muscles around the knee and ankle to hold the joint steady, which is the best protection against a sprain.
Cartilage. Movement circulates the fluid around the joint and keeps the cartilage nourished — it has no blood supply of its own.
Heart and lungs. Cardiac muscle works harder and the breathing rate rises, improving oxygen delivery to every tissue.

Sample answer — yoga. Yoga, described in ancient Indian texts, includes physical postures, breathing and meditation. Holding an asana keeps a muscle contracted without movement, which builds endurance; the stretches slowly increase the range of a joint; weight-bearing postures load the bones of the arms and spine; and the breathing practices improve the expansion of the rib cage, which the flexible cartilage joining the ribs to the sternum makes possible. Research shows yoga improves flexibility, posture and breathing, reduces stress and helps prevent lifestyle diseases.

Tip: whatever practice you choose, write your answer as “this movement → this tissue → this change”. That is what turns a description into a scientific explanation.

Q4.

Reflect on any gardening methods you know, such as pruning, grafting, irrigation or crop rotation. How does each practice support the healthy functioning of plant tissues like meristems, conducting tissues or supporting tissues?

Answer

Each garden practice works on a particular tissue. Match the practice to the tissue and the reason becomes obvious.

Practice	Tissue it acts on	How it helps
Pruning / trimming a hedge	Apical and intercalary meristem	Removing the shoot tip takes away the apical meristem, so the buds at the nodes are released and many side branches sprout — the plant becomes bushier and flowers more
Taking stem cuttings	Meristem at the node	Only a cutting that carries a node with a bud can regenerate — exactly the sugarcane result in Question 10
Grafting and budding	Lateral meristem (cambium) of stock and scion	The two cut surfaces are matched so their cambium layers touch; the dividing cells knit together and their xylem and phloem become continuous, so water and food flow across the join
Irrigation	Xylem, root hair and parenchyma	Keeps the soil moist so root hair can absorb water; maintains the unbroken water column in the xylem and the turgor of parenchyma that keeps soft stems upright. Over-watering, on the other hand, drives air out of the soil and suffocates the roots
Mulching	Root hair and epidermis	Slows evaporation from the soil, so absorption by root hair continues steadily and the plant is not forced to close its stomata
Crop rotation and manuring	All tissues — through mineral supply	Restores nitrogen and minerals that the xylem must carry up. Without nitrogen the plant cannot build protein for new meristematic cells; without calcium it cannot build cell walls
Staking a young plant	Collenchyma and sclerenchyma	Supports the stem while its own supporting tissues are still developing, so it does not break in wind

The common thread: gardening is applied plant anatomy. Every one of these practices either protects a meristem, keeps a conducting tissue supplied and unbroken, or takes some load off a supporting tissue.

Q5.

Turn a nature walk into a research project. (i) Observe different leaves and study their adaptations for various environments, such as desert, very moist or aquatic habitats. (ii) Consult an elder community resource persons about their knowledge on different plant leaves, such as leaves that remain fresh for a long time, repel water or deter insects. Find out their traditional uses, such as making plates, preparing cooling wraps or functioning as insect repellents.

Answer

How to run it as a project: choose 8 – 10 plants growing in different situations near you. For each, record the habitat, and note the thickness and feel of the leaf, how waxy the surface is, whether it is hairy, and whether it is thin and floating or thick and fleshy. Press one leaf of each as a specimen. Then interview an elder and record what the leaf is traditionally used for and why.

Sample answer — part (i):

Habitat	Example	What you observe	Tissue-level reason
Desert / dry	Aak, cactus, khejri, aloe	Thick, fleshy or reduced to spines; a shiny waxy surface; often hairy; few stomata, sunk into pits	Very thick cuticle over the epidermis cuts evaporation; water-storing parenchyma fills the fleshy leaf; hair traps still air and slows water loss
Very moist / shady	Colocasia (arbi), banana, ferns	Large, broad, thin, soft leaves	A thin cuticle and many stomata allow rapid transpiration; the large surface catches the little light available under a canopy
Aquatic — floating	Lotus, water hyacinth	Leaf floats, upper surface waxy and water-repellent, stalk spongy and light	Stomata on the upper surface only; specialised parenchyma with large air spaces gives buoyancy, which is exactly how the book explains floating
Aquatic — submerged	Hydrilla, Vallisneria	Thin, ribbon-like or finely divided leaves; no waxy shine	Almost no cuticle and usually no stomata, because gases and minerals are absorbed directly through the whole surface (see Pause and Ponder Q2)
Saline / coastal	Mangroves	Thick, leathery, often glossy leaves	Thick cuticle limits water loss even though water is all around, because the water is salty and hard to absorb

Sample answer — part (ii), traditional uses: banana and palash leaves are used as pattal (leaf plates) because they are large, waterproof and do not tear when hot food is served; banana leaves also stay fresh for days. Betel and banana leaves are used as cooling wraps for fevers. Neem and tulsi leaves are placed among stored grain and clothes as insect repellents. Turmeric and neem leaves are used on skin infections. Ask your elder why that particular leaf, and you will usually find the answer is the waxy cuticle, the leaf's size and toughness, or a chemical stored in its parenchyma.

Tip: record the local name, the botanical name if you can find it, the habitat and the use, and add your pressed leaf. That turns a walk into a proper piece of documented fieldwork.

Q6.

Study various dance forms of different tribal communities across the country. Each student learn and experience at least five steps. Observe the joint movements involved in performing these steps and then develop a dance or drama on the concept of joint movements. Perform this at the school’s annual function so that students from different grades can learn from it.

Answer

How to build it: divide the class into groups, each taking one dance form. Learn five steps, then write down for each step which joints move and what kind of joint each one is. Turn that table into the script of the performance.

Sample answer — a movement analysis you can start from:

Dance	Characteristic step	Joints in action	Type of joint
Bihu (Assam)	Quick bending at the waist with rapid hip sways	Hip, vertebral column	Ball and socket; the cartilage discs between the vertebrae allow bending and twisting
Ghoomar (Rajasthan)	Continuous spinning with the arms circling overhead	Shoulder, ankle, neck	Ball and socket; hinge; pivot
Santhal / Jhumar (Jharkhand)	Side-stepping in a line with linked arms and a swing of the body	Hip, knee, shoulder	Ball and socket and hinge
Bhangra (Punjab)	High jump with the arms thrown up	Hip, knee, ankle, shoulder	Ball and socket; hinge — the crouch-and-drive of Question 4
Cheraw / bamboo dance (Mizoram)	Stepping in and out between clapping bamboo poles	Ankle, knee, toe joints	Hinge — fast, precise, one plane

A workable script for the performance:

Open with a still tableau; a narrator names the four joint types.
Four short solos, one per joint type — a shoulder swing (ball and socket), an elbow-and-knee sequence (hinge), a head-turn sequence (pivot), and one dancer standing absolutely still with a hand on the head (fixed joints of the skull).
A group section in which each folk form is performed while a placard names the joints it uses.
Close with a short scene: muscles pull, tendons transmit the pull, ligaments hold the bones, and the brain sends the signal — with students labelled as each tissue.

Tip: keep one line on every placard, in both English and your own language, so that students of every grade in the audience can follow the science while they watch the dance.

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