A thorough understanding of Kerala Syllabus 9th Standard Biology Textbook Solutions Chapter 4 Behind Movements Notes Questions and Answers English Medium can improve academic performance.
SCERT Class 9 Biology Chapter 4 Notes Questions and Answers Behind Movements
Std 9 Biology Chapter 4 Notes Pdf Kerala Syllabus English Medium Solutions Questions and Answers
Class 9 Biology Chapter 4 Let Us Assess Answers Behind Movements
Question 1.
Identify the plant movement mentioned in each of those given below.
(a) The pea plant twines around a support
(b) The coconut tree near the bank of a river grows leaning towards the river.
(c) The pollen tube grows towards the ovary.
(d) The leaf of Touch-me-not plant folds while touching.
Answer:
(a) Haptotropism
(b) Phototropism (Sunlight as stimulus promotes the growth of coconut tree towards river)
(c) Chemotropism
(d) Nastic Movement
Question 2.
Identify the disease mentioned in the statement given below.
In some people certain cells of the immune system may destroy the cartilages and synovial membrane.
Answer:
Rheumatoid arthritis
Question 3.
Identify the muscle from the peculiarities given below.
- Cells with single nucleus.
- Spindle shaped cells
Answer:
Smooth Muscle
Question 4.
Observe the joints denoted as X, Y, Z and choose the one which comes in the correct order.
Answer:
c) X-Gliding Joint, Y-Hinge joint, Z-Pivot joint
Question 5.
Disorders of the bones and muscles are given in column 1, and their causes are given in column 2. Analyse them and choose the option including the correct pairs.
| Column I | Column II |
| P) Sprain | i. Destruction of cartilage by certain defense cells |
| Q) Osteoporosis | ii. Changes that occur in genes |
| R) Rheumatoid arthritis | iii. Stretching or breaking of ligaments |
| S) Muscular dystrophy | iv. Deficiency of protein, calcium and Vitamin D |
(a) P – ii, Q – iv, R – i, S – iii
(b) P – iv, Q – iii, R – ii, S – i
(c) P – i, Q – ii, R – iii, S – iv
(d) P – iii, Q – iv, R – i, S – ii
Answer:
(d) P – iii, Q – iv, R – i, S – ii
Question 6.
Re-draw the diagram and answer the following questions.
(a) Identify the parts mentioned below and label them.
i) Fluid present between the bones
ii) The part seen at the tip of bones which reduces friction
(b) Identify the part labelled as ‘ X ‘ in the diagram and write its function.
Answer:
Extended Activities
Question 1.
Collect pictures and information related to the diversity of locomotion in the living world and display them in the class.
Answer:
Question 2.
Prepare posters indicating the importance of exercise using graphics software and display them in the notice board.
Answer:
Question 3.
Observe various organisms in your surroundings and record the diversity in their movements in your Science diary.
Answer:
Following examples illustrate the diverse ways in which organisms move, each adapted to their environment for survival:
- Sparrow: A sparrow flies by flapping its wings rapidly and then gliding before landing on a branch. This movement helps it travel from tree to tree with ease.
- Ants: Ants move in a line using their six legs, walking in a coordinated manner. They can often be seen carrying food back to their nest.
- Dog: A dog moves smoothly on all four legs, walking or running in short bursts when excited or chasing something. This movement allows it to cover ground quickly.
- Fish: Fish swim by moving their tails from side to side. This allows them to navigate smoothly through the water, adjusting speed and direction as needed.
- Touch-me-not Plant (Mimosa pudica): When touched, the leaves of the Touch-me-not plant close rapidly. This movement is a response to touch, helping the plant protect itself.
Behind Movements Class 9 Notes Questions and Answers Kerala Syllabus
Question 1.
What all types of movements can be observed in the organisms in the picture?
Answer:
Prey capturing by birds, Honey capturing and pollination by bees and butterflies, Snakes move by dragging their bodies along the ground, plant leaves move in response to the wind in a variety of ways, including bending, twisting, and vibrating, plant parts grow towards the light, roots grow towards water, etc.
Question 2.
Observe the illustration and note down the importance of movement in each organism.
Answer:
- Food acquisition in amoeba
- Respiration in human beings (Both Expiration and inspiration)
- Growth of plant stem towards light
- The tiger, as a predator, captures its prey (deer) for its survival.
Question 3.
List out other kinds of movements that you are familiar with.
Answer:
- Movement of an organism from one place to another. Examples include walking, running, swimming, flying, and crawling.
- The movement of cells within an organism, such as during development or immune response.
- The movement of an object around a fixed axis. Examples include the spinning of a top or the rotation of the Earth.
Question 4.
Analyse the illustration based on the indicators and note down the inferences regarding the diverse movements in the living world.
Indicators:
- Movements in plants
- Movements in animals
- Common movements
- Microscopic and macroscopic movements
Answer:
a) Movements in plants:
- Plants cannot move from place to place.
- E.g., Seed germination, Change in parts of the plants according to stimuli
b) Movements in animals:
- Animals can change in a part of the body or position of the body with respect to the surroundings.
- E.g., The movement of sperm, Peristalsis during digestion, heartbeat, blood circulation, walking, running, jumping, etc.
c) Common movements:
- Transport of substances through osmosis, diffusion, active transport, transport of gases and nutrients, expulsion of waste, etc.
d) Microscopic and macroscopic movements:
- Microorganisms also exhibit various kinds of movements.
- E.g., Body movement in bacteria using flagella, Pseudopodia (false feet) in amoeba for locomotion and engulfing food particles, and movement in paramecium using cilia.
There is a great diversity in movements among organisms.
Question 5.
Identify the means of movement of the organisms shown in the illustration and complete it.
Answer:
Organisms exhibit different kinds of movements for their survival. There are different means in organisms that support these movements.
| Organisms | Means of movements |
| Paramecium | Move using cilia, which are short, hair-like structures that cover their entire cell body. |
| Euglena | Move using a flagellum, a long, whip-like structure that acts as a motor. |
| Fishes | Possess a streamlined body that helps them to swim in the water. They swim with the help of their fins and their tails. |
| Frogs | Exhibit Toad movement. The hind limbs of frogs are muscular and strong and help in hopping long distances. And the webbed feet also help them in swimming. |
| Whale | Whales use their flippers and tail fin to move in water. |
| Birds | Birds use a variety of means of movement, including flight, walking, swimming, diving, jumping, etc. |
Question 6.
Expand the given table by including more organisms as given above.
| Organisms | Means of movement |
| Bacteria | |
| Amoeba | |
| Hydra | |
Answer:
| Organisms | Means of movement |
| Bacteria | Bacterial movement typically involves the use of flagella. |
| Amoeba | Move by using pseudopodia, or false feet, in a process called amoeboid movement. |
| Hydra | Somersaulting, Sliding, Amoeboid motion. Floating |
| Cockroach | Flying and Crawling |
| Snake | Slithering |
| Duck | Swimming and walking |
| Snail | Slithering |
Question 7.
Haven’t you understood the means of movement in different organisms? How does movement occur in humans? What are the means involved? Discuss, collect more information and complete the illustration.
Answer:
- Flagellar Movement: Sperm travels through the female reproductive tract to meet the ovum/egg by whipping its tail is an example of flagellar movement.
- Ciliary movement: Fertilised egg travels through the fallopian tube and reaches the uterus for implantation as a result of wave-like movement exhibited by fine hair present in the fallopian tube (cilia).
Question 8.
The discovery of movements and locomotion in humans is caused by the functioning of muscles. Which characteristics of muscles help in movement? Write the answer based on the indicators given below:
- Characteristics of muscle tissues
- Proteins in muscle cells and their importance
Answer:
Different body movements and locomotion are made possible by specialised tissue called muscles. They are formed of muscle cells. Unlike other cells, muscle cells contain more microfilaments made of proteins, such as Actin and Myosin. These filaments act together in the contraction and relaxation of muscles, which enables body movements.
There are different types of muscles in the body. They are:
Skeletal Muscles: Cylindrical-shaped cells with striations, and they do not show branching (Unbranched). More number of nuclei are present in a single cell (Multinucleated). Movements of the skeletal muscles can be controlled by one’s will (Voluntary muscles). These muscles are found attached to the bones.
Smooth Muscles: Spindle-shaped cells with tapered ends present in internal organs like the stomach. They are non-striated, uni-nucleated (cells with a single nucleus) and involuntary muscles (movements that cannot be controlled by will).
Cardiac Muscles: Cardiac muscles are muscles of the heart. They are involuntary, multinucleated, striated, branched, cylindrical-shaped cells.
Question 9.
How does Actin and Myosin help in the contraction of muscles? Find out.
Answer:
Actin is a thin protein filament that provides sites where myosin can attach during contraction. Myosin is a thicker protein filament with heads that stick out. These heads bind to actin during muscle contraction. When a muscle gets a signal to contract, calcium ions are released, exposing the binding sites on Actin.
The Myosin heads then attach to these sites, forming a cross-bridge. After attaching, the Myosin heads pull the Actin filaments inward, making the muscle shorter, which causes the muscle to contract. After the pulling action, the cross-bridge is broken, releasing actin from myosin, and muscle cells regain their original size; thus, muscle relaxation occurs. This repeated cycle of Myosin pulling on actin makes muscles move in a body.
Question 10.
Analyse the illustration, do the given activity and complete the table.
Answer:
| Muscles attached to the bones | Muscles in the hollow internal organs | Muscles in the walls of the heart | |
| Name of the muscle | Skeletal Muscle | Smooth Muscle | Cardiac Muscle |
| Shape of the cell | Cylindrical | Spindle | Cylindrical |
| Presence of striations | Striated | Non-striated | Striated |
| Branches | Unbranched | Unbranched | Branched |
| Control of the muscles according to one’s will. | It can be controlled according to one’s will | It cannot be controlled according to one’s will | It cannot be controlled according to one’s will |
Question 11.
Some muscles in our body that can be controlled (voluntary muscles) and some others cannot be controlled (involuntary) according to our will. In which all parts of the body are each one of these found? Find out examples through discussion and note them down in the table provided.
Answer:
| Voluntary muscles | Involuntary muscles |
| Muscles in the hands Muscles in the legs Muscles found in the neck and back |
Muscles in the oesophagus Muscles in the stomach Muscles in the intestine |
Question 12.
By folding and stretching your hands and analysing the illustration, understand the contraction and relaxation of muscles. Discuss on the basis of indicators and prepare notes.
- The part that connects muscles to bones.
- Muscles involved in the movement of hands.
- The importance of connecting the two tips of the muscles to two bones.
- The change that should occur to the two muscles in order to fold the hands.
- The changes that should occur to the two muscles in order to stretch the hands.
Answer:
The contraction and relaxation of muscles in hand movements rely on tendons, which connect muscles to bones and allow the transfer of force to create movement. Muscles must be attached to two different bones so that when they contract, they can pull on the bones and create movement at the joint. This connection enables the hand to bend or stretch.
The main muscles involved are the biceps (Flexor muscle) and triceps (extensor muscle). To bend the arm, the biceps contracts and the triceps relaxes, pulling the hand upwards. In contrast, to straighten the arm, the triceps contracts while the biceps relaxes, allowing the arm to extend. This coordinated action of muscles attached to two different bones ensures smooth hand movements.
Question 13.
Analysing the given illustration and developing an understanding of the two divisions in the human skeletal system. Label the parts and complete the illustration.
Answer:
The human skeleton is divided into two divisions, namely, the Axial skeleton and the appendicular skeleton.
In human beings, muscles are connected with the help of either bones or cartilage. Diversity of movements are made possible due to the combined action of muscles and bones. The human skeleton is the internal framework of the human body. It is composed of around 270 bones at birth and this total decreases to around 206 bones by adulthood after some bones get fused together. It can be broadly divided into two types:
- Axial skeleton ( 80 bones): It consists of the bones seen in the central axis of the body.
- Appendicular skeleton (126 bones): It consists of the bones which are connected to the central axis.
Structure Of Bone
About 18 % of the human body weight is constituted by bones. They provide structure, support and protection to the body. Each bone is covered by a membrane known as periosteum. Blood vessels, nerves and lymph vessels are also found in bones. The components that provide hardness and strength to the bones include calcium, phosphate, collagen proteins and salts. Osteoblast cells deposit minerals in the bones which makes them strong and firm and also helps in the growth and repair of the bones.
Cartilage
It is the connective tissue which is softer and more flexible than bones. Cartilage is present in elbows, knees, ankles, at the tip of ribs, between the vertebrae of the vertebral column, pinna of the ear, tip of the nose and also in the trachea. Cartilages present at the tip of the bones reduce friction in the joints. Blood vessels and nerves are absent in them. The growth of cartilage cells is slower than the rest of the cells because of the absence of blood vessels.
Diversity In Structural Framework
All organisms do not have a skeletal framework (endoskeleton) like that of human beings; it varies from organism to organism. Hydroskeleton, exoskeleton and endoskeleton are some of the types of structural frameworks of the body present in different organisms.
Structure Of Bone
About 18 % of the human body weight is constituted by bones. They provide structure, support and protection to the body. Each bone is covered by a membrane known as periosteum. Blood vessels, nerves and lymph vessels are also found in bones. The components that provide hardness and strength to the bones include calcium, phosphate, collagen proteins and salts. Osteoblast cells deposit minerals in the bones which makes them strong and firm and also helps in the growth and repair of the bones.
Cartilage
It is the connective tissue which is softer and more flexible than bones. Cartilage is present in elbows, knees, ankles, at the tip of ribs, between the vertebrae of the vertebral column, pinna of the ear, tip of the nose and also in the trachea. Cartilages present at the tip of the bones reduce friction in the joints. Blood vessels and nerves are absent in them. The growth of cartilage cells is slower than the rest of the cells because of the absence of blood vessels.
Diversity In Structural Framework
All organisms do not have a skeletal framework (endoskeleton) like that of human beings; it varies from organism to organism. Hydroskeleton, exoskeleton and endoskeleton are some of the types of structural frameworks of the body present in different organisms.
Hydroskeleton
- Fluid filled chambers are present in the body of the earth worm.
- Here, water is the means to maintain body structure and locomotion. This mechanism is commonly called hydroskeleton.
- Hydroskeleton helps in the movements of hydra and snail.
Exoskeleton
- They connect muscles in respective places and help in movement, locomotion and protection of the body.
- Hard shells present in crabs, mussels and oysters made up of calcium carbonate, outer covering of grasshoppers and cockroaches made up of chitin are examples of exoskeleton.
Endoskeleton
- It provides shape to the body, protects internal organs and helps in movement and locomotion.
- It is seen in vertebrates including human beings which is made up of a framework of cartilages and bones.
Joints
Joints are the connection between two or more bones. Connecting the bones with the help of joints makes movement easier. They help to rotate our shoulders, bend our knees and elbows, swivel our neck and more. Joints differ according to their functions.
Structure of a typical joint
A typical joint consists of the following parts:
- Ligaments – They are found connecting two bones.
- Capsule – It is seen inside the ligament which helps in the smooth movement of the bones.
- Cartilage – It is seen covering the tip of each bone, which reduces the friction between the bones.
- Synovial fluid – The fluid present between the two bones of a joint which also reduces the friction between the bones.
- Synovial cells – Synovial fluid is produced by these cells, which is present in the synovial membrane.
Different types of joints
Based on the functions, there are different types of joints:
- Ball and socket joint
- Hinge joint
- Pivot joint
- Gliding joint
| Name | Ball and Socket joint | Hinge joint | Pivot joint | Gliding joint |
| Peculiarities | The ball-shaped surface of one round bone fits into the cup-like depression of another bone, allowing greater freedom of movement | Allows movement only in one axis. | Enables movement in different directions | Allows movement only in two axes |
| Position | Shoulder joint. | Ankle joint | Between the atlas and axis | Wrist joint |
Body growth and Bone Development
Growth during childhood and adolescence is associated with the development of the skeletal system. Childhood and adolescence is a critical period for bone development. It is essential that calcium should deposit in the bones to ensure their hardness and strength. Calcium-rich foods (dairy, fish, leafy greens) and vitamin D (sunlight, eggs, fish) are essential. Protein (meat, beans) also supports bone growth. As age advances, the density of bones decreases, making them weaker and more prone to fracture. A balanced diet throughout life helps maintain bone density and reduce the risk of osteoporosis.
Muscle And Exercise
The active functioning of muscle cells can be ensured only through movement. Exercise helps to strengthen muscles and increase their efficiency.
| Part of the body | The benefits of exercise |
| Lungs | Vital capacity increases, gaseous exchange becomes efficient, strengthens respiratory muscles, improves oxygen utilization, reduces risk of respiratory diseases, promotes alveoli health. |
| Hands and legs | Improved muscle strength. enhanced flexibility and range of motion, reduces the risk of sprains, strains, increases oxygen and nutrients, increases bone density improvement. |
| Muscles, bones | Increased muscle strength, enhanced muscle coordination, increased bone density, enhanced joint function, improved posture and balance. |
| Heart and blood vessels | Strengthening the heart muscles. lo ers blood pressure, improves blood vessel health, lowers cholesterol levels, reduces risk of blood clots, helps in weight management |
Vital Capacity
The total volume of air exhaled forcefully after a deep inhalation is called vital capacity. It is the measurement of a person’s respiratory health. It’s typically 4.5 litres in men and 3 litres in women. A decrease in vital capacity may be an indication of pulmonary diseases.
Question 14.
Write the total number of bones in the human skeleton.
Answer:
206 bones
Question 15.
Mention the number of bones in the axial skeleton and appendicular skeleton in the human skeleton.
Answer:
Axial skeleton – 80 bones, Appendicular skeleton – 126 bones.
Question 16.
Is the number of bones same in children and adults? What is the reason? Find out.
Answer:
No, the number of bones is not the same in children and adults. Babies are born with approximately 300 bones while adults have only 206. The reason behind this is that the babies are born with bone made of cartilage which is flexible. As children grow, this cartilage gradually hardens and fuses together, forming the stronger, more rigid bones of adulthood.
Question 17.
Which substances are responsible for the hardness of bones?
Answer:
The hardness of bones is due to the presence of calcium, phosphate, collagen proteins and salts.
Question 18.
What is the function of osteoblast cells of bones?
Answer:
It helps to deposit minerals in the bones which makes them strong and firm and helps in growth and repair.
Question 19.
Muscles are connected either to bones or to cartilages. What is the difference between bones and cartilage?
Answer:
| Bones | Cartilages |
| It is very strong and firm when compared to cartilage. | It is softer and more flexible than bones. |
| Blood vessels, nerves and lymph vessels are present. | Blood vessels and nerves are absent. |
| They grow at a faster rate due to the presence of blood vessels. | Their growth is slower than the rest of the cells due to the absence of blood vessels. |
Question 20.
Do all living organisms have a skeletal framework like that of humans?
Answer:
No
Question 21.
Complete the given illustration regarding the diversity in the structural framework of organisms. (Fill the square boxes with their characteristics and pentagonal boxes with suitable examples).
Answer:
Question 22.
Are there parts of exoskeleton in organisms with endoskeleton? Discuss and find out.
Answer:
Yes, some organisms have both an endoskeleton and an exoskeleton, including tortoises and crocodiles.
Question 23.
Some organisms having exoskeleton shed their outer covering. Why? Find out.
Answer:
Organisms with exoskeletohs, such as insects, prawns and spiders, shed their outer covering because if the exoskeleton becomes damaged or injured, it provides an opportunity for the organism to repair the damage and regenerate lost parts. In some insects, they shed their outer covering to remove the parasites or other harmful organisms that have attached themselves to their exoskeleton.
Question 24.
Analyse the figure of the joints and complete the table.
Answer:
Based on the functions, there are different types of joints:
- Ball and socket joint
- Hinge joint
- Pivot joint
- Gliding joint
| Name | Ball and Socket joint | Hinge joint | Pivot joint | Gliding joint |
| Peculiarities | The ball-shaped surface of one round bone fits into the cup-like depression of another bone, allowing greater freedom of movement | Allows movement only in one axis. | Enables movement in different directions | Allows movement only in two axes |
| Position | Shoulder joint. | Ankle joint | Between the atlas and axis | Wrist joint |
Question 25.
Collect more information about joints in different parts of the body. Prepare a chart and exhibit it in the class.
Answer:
| Types of joints | Location | Description |
| Immovable | Skull, Pelvis, Sternum | Bones are fused together and do not allow any movement |
| Slightly movable | Vertebral column | Bones are connected by cartilage and allow limited movement |
| Freely movable | Shoulders, Hips, Knees, Elbows, Wrists, Ankles |
Bones are separated by a synovial cavity, allowing for a wide range of movements. |
Question 26.
What are the other functions of bones? Discuss and expand the list.
Answer:
The following are the functions of bones:
- Formation of blood cells
- Enables body movement
- Bones protect vital organs, such as the brain, heart, lungs, and spinal cord.
- Bones help regulate the body’s pH balance by absorbing or releasing minerals.
- Provides a structural framework for the body, supporting organs and tissues.
- Bones can store heavy metals and other toxins, helping to remove them from the body.
Question 27.
How does the deficiency of vitamin D affect the body? Find out.
Answer:
Vitamin D is essential for calcium absorption which is vital for strong bones. A deficiency can lead to osteoporosis, a condition characterized by weak, brittle bones that are susceptible to fractures. In children, vitamin D deficiency can cause rickets, a disease characterized by soft, weak bones that can lead to bowed legs and other deformities.
Vitamin D plays a role in regulating the immune system. A deficiency can impair the immune response, making individuals more susceptible to infections. Vitamin D deficiency has been associated with an increased risk of heart disease, including high blood pressure and stroke.
Question 28.
Complete the following table on disorders of bones and muscles.
Answer:
| Disease | Causes | Symptoms |
| Osteoporosis | Deficiency of protein, calcium and vitamin D | Back pain, frequent bone fractures, etc. |
| Rheumatoid arthritis | The immune system destroys cartilage and synovial membrane. | Severe pain and swelling of joints |
| Muscular dystrophy | Changes in genes | Weakening and degeneration of muscles. |
| Muscular dystrophy | Injury caused by stretching or breaking of ligaments. | Pain, swelling, bruises, difficulty in moving joints. |
Question 29.
Why is rheumatoid arthritis more in women than men? Find out.
Answer:
Rheumatoid arthritis (RA) is more common in women largely due to hormonal factors. The hormone estrogen, which is present in higher levels in women, is thought to affect the immune system. Estrogen can influence how the immune system responds, and fluctuations in this hormone, especially during pregnancy or menopause, can increase the risk of developing RA or make the symptoms worse.
During pregnancy, estrogen levels rise, which may temporarily improve RA symptoms, but after childbirth, when estrogen levels drop, the symptoms can flare up. Similarly, during menopause, when estrogen levels decrease significantly, women are more likely to experience the onset or worsening of RA. These hormonal changes play a key role in why women are more affected by RA than men. Other than this, stronger immunity and genetic factors increase the risks of rheumatoid arthritis in women than in men.
Question 30.
Identify the situations in which the first aid measures shown in the pictures are used and complete the illustration.
Answer:
First aid measures are crucial in stabilising injuries before professional medical treatment.
Sling: A sling is used to support and immobilise an injured arm or shoulder. It is typically used when someone has a fracture, dislocation, or severe sprain in the arm, wrist, or shoulder area. The sling helps to keep the injured part stable and prevents further movement, reducing pain and promoting healing.
Splint: A splint is used to keep an injured limb, such as a leg or arm, immobile. It is commonly used in cases of a fracture, severe sprain, or dislocation to prevent further injury. The splint provides support and protection to the injured area, ensuring that it remains in a fixed position until professional medical help is available.
Bandage: A bandage is used to cover wounds, support injured limbs, or secure dressings in place. It is commonly applied in cases of cuts, scrapes, bleeding, or sprains to protect the injury, stop bleeding, and provide support. Bandages are also used to prevent infection in open wounds and keep dressings clean.
Question 31.
Organise an awareness class by a health expert about first aid measures in coordination with the Health Club. Get hands-on training on the first-aid measures given
- How to prepare a sling
- How to use a splint
- How to prevent blood loss when a wound occurs
- The use of bandage and band-aid
- First aid to be given when there is a spinal injury.
Answer:
First aid is the immediate help we can give to someone who is injured or sick before professional medical help arrives. Having basic first aid knowledge enables one to act quickly in emergencies and can make a big difference in someone’s life. Here are some general instructions to perform first aid in particular situations:
A sling is used to support an injured arm or shoulder. To make one, use a triangular cloth placed under the injured arm, with the ends tied around the neck. Ensure the elbow is well-supported and the arm is immobilised without cutting off circulation.
A splint is needed to stabilise a broken or injured limb. Place a firm object, like a stick, along the injured area and tie it in place with bandages or cloth strips. Ensure it immobilised the limb but isn’t too tight to affect circulation.
To stop bleeding, apply direct pressure on the wound with a clean cloth or bandage. If possible, elevate the injured area above heart level and continue applying pressure until the bleeding slows or stops.
Bandages and band-aids both protect wounds but differ in use. Bandages are larger cloth or gauze used to cover and support bigger injuries, like cuts or sprains, often with extra dressings. Bandaids are small adhesive strips for minor cuts or scrapes, covering the wound directly to prevent infection. Bandages provide more support, while band-aids are for quick use on smaller injuries.
For suspected spinal injuries, avoid moving the person. Keep the head, neck, and spine aligned, and stabilise them with rolled towels if possible. Call for emergency help and move the person only if necessary.
Question 32.
Analyse the figure, discuss and find out the various plant movements and the stimuli that cause movements in plants.
Answer:
| Type of movement | Stimuli | Directional/Non-directional |
| Curling of tendrils around a support | Touch | Directional |
| Bending of stern in the presence of light | Light | Directional |
| Folding of leaves of touch-me-not plant | Touch | Non-directional |
| Drooping of leaves after sunset | Light | Non-directional |
Question 33.
Are all the plant movements that you have listed related to the direction of stimulus? Discuss.
Answer:
No. All plant movements are not related to the direction of the stimulus. Based on the findings, plant movements can be classified into:
Question 34.
Analyse the illustration, identify how the movements of the shoot and root are related to the direction of stimulus and complete the table.
Answer:
| Plant movements | Stimulus | Direction of movement of the shoot | Direction of movement of the root |
| Phototropism | Light | Towards light | Away from light |
| Geotropism | Gravity | Away from gravity | Towards gravity |
| Hydrotropism | Water | Away from water | Towards water |
Question 35.
Two other tropic movements found in plants are given in illustration. Find out the characteristics of these and record them in ‘our science diary.
Answer:
Haptotropism: Directional movement of plant parts in response to stimulus touch or contact with a solid surface. E.g. Tendrils of climbers curl around the support they grow.
Chemotropism: Growth of plant parts towards or away from chemical stimulus. E.g. Germination and growth of pollen tube towards the egg/female gamete in flowering plants.
Question 36.
Have you ever touched a Touch-me-not plant? How is the movement of the leaves of a Touch-me-not plant? Which type of movement is this? What is the peculiarity of such movements?
Answer:
When we touch a touch-me-not plant, the leaves of the plant fold immediately in response to the stimulus touch. This type of plant movements are called nastic movements. They are non-directional. i.e., they do not depend on the direction of stimulus. It happens because of changes in water pressure inside the plant’s cells, helping the plant protect itself from possible harm, like being eaten by predators.
Question 37.
List out more examples of nastic movements
Answer:
Examples of nastic movements:
- Leaves of certain plants (prayer plant, oxalis) fold during the night and spread out during the daytime.
- Opening and closure of jasmine flowers during night and day, respectively.
- Leaves of Venus fly trap shut when an insect sits on it.