These NCERT Solutions for Class 7 Science Chapter 11 Transportation in Animals and Plants Questions and Answers are prepared by our highly skilled subject experts to help students while preparing for their exams.
Transportation in Animals and Plants NCERT Solutions for Class 7 Science Chapter 11
Class 7 Science Chapter 11 Transportation in Animals and Plants Textbook Exercise Questions and Answers
Match structures given in Column I with functions given in Column II.
|Column I||Column II|
|l. Stomata||(a) Absorption of water|
|2. Xylem||(b) Transpiration|
|3. Root hair||(c) Transport of food|
|4. Phloem||(d) Transport of water|
|(e) Synthesis of carbohydrates|
Fill in the blanks.
a. The blood from the heart is transported to all parts of the body by the ……………….
b. Haemoglobin is present in ………………. cells.
c. Arteries and veins are joined by a network of ……………….
d. The rhythmic expansion and contraction of the heart is called ……………….
e. The main excretory product in human beings is ……………….
f. Sweat contains water and ……………….
g. Kidneys eliminate the waste materials in the liquid form called ……………….
h. Water reaches great heights in the trees because of suction pull caused by ……………….
b. red blood,
Choose the correct options:
a. In plants, water is transported through
(iv) root hair
b. Water absorption through roots can be increased by keeping the plants
(i) in the shade
(ii) in dim light
(iii) under the fan
(iv) covered with a polythene bag
(iii) under the fan
Why is transport of materials necessary in a plant or in an animal? Explain.
Every cell of plants and animals needs nutrients and oxygen for performing various metabolic activities. Different types of waste products are created during these metabolic activities. Transport of materials is necessary to supply the required substances and to remove the waste products from the cells.
What will happen if there are no platelets in the blood?
The blood platelets are responsible for clotting of blood in case of an injury or a scratch. As we know, when an injury occurs the blood starts flowing for a while and then it clots on its own. If in any case, there are no platelets, the blood will not be able to clot and keeps on flowing. Huge loss of blood will ultimately lead to death.
What are stomata? Give two functions of stomata.
The lower surface of the leaves have small openings. These openings or pores are called stomata. These pores are surrounded by guard cells.
Functions of stomata:
- It helps to eliminate excess water from the plant, i.e, transpiration.
- The process of loss of water from stomata will cause an upward pull, i.e., suction pull which in turn helps in absorption of water from the roots.
- They are responsible for the exchange of gases for respiration.
Does transpiration serve any useful function in the plants? Explain.
- By creating a suction pull, it enhances the absorption of dissolved minerals and water in the plants.
- It helps in getting rid of the excess water in plants.
- It transports minerals and water to the leaves. The leaves use the water to carry out photosynthesis.
- It creates a cooling effect in plants.
What are the components of blood?
Blood is composed of four main components:
- Plasma: It is the liquid part of the blood which is yellowish in colour and contains 90% water. It also contains enzymes, food, proteins and other wastes.
- Red Blood Cells: They are disc-shaped cells containing a red-coloured pigment called haemoglobin in it. Haemoglobin helps in transportation of oxygen.
- White Blood Cells: These are the fighting cells and are also called as warrior cells which protect us from infections caused by bacteria and foreign materials.
- Platelets: The platelets help in clotting of the blood.
Why is blood needed by all the parts of a body?
All the parts of the body need food and oxygen, which is carried to them by blood. They also release their wastes into the blood which is then transported to those parts from where they can easily be removed. Hence, blood is needed by all parts of the body.
What makes the blood look red?
Haemoglobin present in blood is a red pigment. This pigment is responsible for carrying oxygen to various parts of the body through blood and makes it appear red.
Describe the function of the heart.
The human heart is divided into four chambers. The upper two chambers are called right and left atria and the lower two chambers are called the right and left ventricles. Right atrium receives carbon dioxide-rich blood from the body. Blood from right atrium enters the right ventricle, which contracts and pumps the blood to the lungs for purification.
On the other hand, oxygen rich blood from the lungs returns to the left atrium. From the left atrium, blood enters left ventricle. Left ventricle contracts and pumps the blood to all parts of the body. Hence, the rhythmic contraction and expansion of various chambers of the heart maintains the transport of blood and oxygen to all parts of the body.
Why is it necessary to excrete waste products?
All cells of our body produce waste products. These waste products are toxic to the body and therefore need to be excreted out. This process of removing waste products produced in the cells of living organisms is called excretion.
Draw a diagram of the human excretory system and label the various parts.
NCERT Extended Learning Activities And Projects
Find out about blood groups and their importance.
The best-known way of grouping of blood types is the ABO system, although there are other groups too. Within the ABO group, four major categories are divided into eight common blood types: A, B, O and AB. Here, alphabets A and B refer to certain substances which are present in the Red Blood Cells. The blood group AB contains both A and B substances in the RBCs whereas, both these substances are absent in the blood group O.
The grouping is very important when it comes to having a blood transfusion. If blood is given to a patient that has a blood type that is incompatible with the blood type of the blood that the patient receives, it can cause intravenous clumping in the patient’s blood which can be fatal.
When a person suffers from chest pain, the doctor immediately takes an ECG. Visit a doctor and get information about ECG. You may even look up an encyclopaedia or the internet.
An electrocardiogram (ECG) is a medical test that detects cardiac (heart) abnormalities by measuring the electrical activity generated by the heart as it contracts. The machine that records the patient’s ECG is called an electrocardiograph. The electrocardiograph records the electrical activity of the heart muscle and displays this data as a trace on a screen or on paper. This data is then interpreted by a medical practitioner. ECGs from healthy hearts have a characteristic shape. Any irregularity in the heart rhythm or damage to the heart muscle can change the electrical activity of the heart so that the shape of the ECG is changed.
A doctor may recommend an ECG for people who may be at risk of a heart disease because there is a family history of heart disease or because they smoke, are overweight, or have diabetes, high cholesterol or high blood pressure.
Objective: To prepare a simple stethoscope of your own.
Materials Required: A glass funnel, rubber tubes and a piece of rubber sheet
- Take a small funnel of 6-7 cm in diameter.
- Fix a rubber tube (50 cm long) tightly on the stem of the funnel.
- Stretch a rubber sheet or a balloon on the mouth of the funnel and fix it tightly with a rubber band.
- Put the open end of the tube on one of your ears.
- Place the mouth of the funnel on your chest near the heart.
- Listen carefully to the thumping sound. The thumping sound is the heart beat.
- Count the heartbeats per minute.
- Now run for 4-5 minutes and again count your heart beats.
- Your stethoscope is ready.
Observations: It can be observed that the heartbeat increases after running. Also, at rest, heartbeats around 72 times per minute.
Conclusion: The pulse rate of an adult person while resting is 72 to 80 beats per minute. A physical activity demands more oxygen, hence, heart beats faster.
Excretion: As our body carries out its daily activities it produces waste materials. These waste materials have to be removed from the body, otherwise they become harmful. The process by which the organisms remove waste products from their body is called excretion. The organ system involved in this process constitutes the excretory system.
Human Excretory System: It consists of kidneys, ureters, urinary bladder and urethra.
i. Kidneys: Kidneys are bean-shaped. They work like filters. They filter only unwanted substances from the blood. There are two kidneys in the human body, one each on the right and left side of the abdomen. These are located on either side of the vertebral column, just below the level of the stomach. They filter the blood and the useful substances are absorbed back into the blood white unwanted waste is dissolved in water and removed as urine.
ii. Ureter: The tube through which urine travels through the kidneys and get stored in the bladder is called ureter Human body has a pair of ureters, one attached to each kidney.
iii. Urinary bladder: The two ureters carry urine from both the kidneys to a bladder called the urinary bladder. In the urinary bladder, urine is temporarily stored.
iv. urethra. Finally, the urine is ejected through a urinary passage called urethra. It is a muscular tube with urinary opening at the end.
Excretion of Urine: Urine contains 95% water, 2.5% urea and 2.5% other wastes. Protein is made up of nitrogen. Metabolism of proteins creates nitrogenous wastes in the body. The nitrogenous wastes are formed by the breakdown of proteins into products such as ammonia. Ammonia is later on converted into urea. In this process, a small amount of uric acid is also formed. Urea is less harmful as compared to ammonia. Accumulation of urea in blood may even cause death. This urea is removed from the blood by filtration through kidneys in the form of urine. Urine is expelled out from time to time. An adult human being normally passes 1-1.8 L of urine in 24 hours.
Sweat: It is the moisture exuded through the pores of the skin. Sweat is produced by sweat glands in the skin. It removes water and salts from the body. When we sweat, it helps to cool our body. It is also an excretory mechanism to get rid of unwanted wastes such as excess water and some salts.
Dialysis: Sometimes a person’s kidneys may stop working due to infection or injury. As a result of kidney failure, waste products start accumulating in the blood. Such persons cannot survive unless their blood is filtered periodically through an artificial kidney. This process is called dialysis.
Mode of Excretion in Other Animals: The way in which waste chemicals are removed from the body of the animal depends on the availability of water.
- Aquatic animals like fishes, excrete cell waste as ammonia which directly dissolves in water.
- Some land animals like birds, lizards, snakes excrete a semi-solid, white coloured compound (uric acid).
- The major excretory product in humans is urea.
- In unicellular organisms like Amoeba and Paramecium, excretory products are removed by diffusion from the body of the organism into the surrounding water.
Transportation is Plants: In plants, water and minerals are absorbed by the roots. Roots have hair, known as root hair which increase the surface area of root for the absorption of water and mineral nutrients dissolved in water. This needs to be transported to the leaves so that they can prepare food. Also, the food prepared by leaves needs to be transported to rest parts of the plant.
Vascular Tissues: Plants have pipe-like vessels to transport water, nutrients and foods which are called vascular tissues. A tissue is a group of cells that perform specialised functions in an organism. They can be seen forming a fine network in a leaf. This network in a leaf is called venation. Plants have two main types of vascular tissues:
- Xylem: It is the vascular tissue for the transport of water and minerals. The xylem forms a continuous network of channels that connects roots to the leaves through the stem and branches and thus transports water to the entire plant.
- Phloem: The phloem consists of vessels, called sieve tubes. It is the vascular tissue that transports the food synthesised in the leaves to all parts of the plant.
Objective: To demonstrate transportation of water through the cells.
Materials Required: A large potato, sugar solution, pin, a petri dish and water.
- Take a large raw potato and cut it into two halves.
- Now take one cut potato piece and peel off its outer skin.
- Cut its round end slightly to make its base flat.
- Make a deep cavity in the centre of the potato piece.
- Fill half of the cavity of potato piece with sugar solution and mark the level of sugar solution in it by inserting a pin through the potato wall as shown the figure.
- Place this potato piece (with sugar solution in it) in a petri-dish containing small amount of pure water.
- The level of water in the petri-dish should be below the level of pin inserted in the potato.
- Allow the apparatus to stand for a few hours.
Observation: After a few hours, the level of sugar solution in the potato piece rises above the level of pin marks. This means that there is an increase in the level of sugar solution inside the potato cavity.
Conclusion: Water can move from cell to cell in the potato wall and reach inside the cavity. In the same way, water reaches xylem vessels of the root from the soil.
Transpiration: In plants, the excess water evaporates through the stomata present on the surface of the leaves by the process of transpiration. The evaporation of water from leaves generates a suction pull (the same that you produce when you suck water through a straw) which can pull water to great heights in the tall trees.
Benefits of Transpiration: It helps in the transport of water and minerals from the soil to the leaves. Also, the water evaporated due to transpiration produces a cooling effect which helps to protect delicate cells of plants from being destroyed by the sunlight.
Class 7 Science Chapter 11 Transportation in Animals and Plants Additional Important Questions and Answers
Very Short Answer Type Questions
What is removed along with water as sweat?
Extra salts are removed along with water as sweat.
What is the function of stethoscope?
Stethoscope is used by doctors to amplify heartbeat so that it can be analysed properly.
What is pulse?
Throbbing sensation that occurs in arteries due to flowing of blood is called pulse.
How is a clot formed?
Clot is produced as an action of platelets during any external injury to prevent excessive loss of blood.
What is meant by excretion?
It is the process of removal of toxic substances from the body.
Name the two main types of blood vessels.
Arteries and veins.
Where is heart located in human body?
Heart is located in the chest cavity with its lower part slightly tilted towards the left.
What is heartbeat?
The muscles of the heart contract and relax, constituting a heartbeat.
Name the various waste products formed in the body.
Urea, uric acid and excess water.
Why is urine yellow in colour?
Urine is yellow-coloured due to the presence of urochrome pigment.
What is urine?
The mixture of various wastes with water filtered from the blood is called urine.
What is vascular tissue?
Plants have pipe-like cells to transport water, nutrients and food which are called vascular tissues.
What is Xylem?
The vascular tissue which is used to transport water and nutrients in the plants is called xylem.
What is Phloem?
The vascular tissue which is used to transport food to all parts of the plant is called phloem.
Why are valves present in veins?
Valves are present in veins to prevent backflow of blood in them.
What is sweat?
Salts and urea are removed along with water from the skin as sweat.
What are capillaries?
Arteries divide into smaller vessels. On reaching the tissues, they divide further into extremely thin tubes called capillaries.
Short Answer Type Questions
What is the main function of the kidneys?
The kidneys perform the essential function of removing waste products from the blood and produce urine which is composed of wastes and extra fluid. It helps in regulating the water-fluid levels in the body.
How do plant roots absorb water and minerals from the soil?
Plants absorb water and minerals by the roots. The roots have root hair, that increase the surface area of the root for the absorption of water and mineral nutrients dissolved in water. The root hair is in contact with the water present between the soil particles.
What is transpiration? How is it useful to the plants?
It is the process of removal of extra water in the form of water vapours through stomata in plants. This process helps in eliminating extra water from the plant body and keeping the plant cool.
What are the three types of cells present in the blood of humans?
The three types of cells present in human blood are:
- Red blood cells (RBCs) which contain a red pigment called haemoglobin.
- White blood cells (WBCs) which fight against germs that may enter our body.
- Platelet cells which helps in the clotting of the blood.
Write the functions of blood?
Functions of blood:
- It carries oxygen from lungs to body cells.
- It removes waste from the cells.
- It regulate body temperature.
- It protects the body against infections.
- It transports nutrients to all body cells.
What is meant by translocation? Where does it take place?
The transport of soluble products of photosynthesis from leaves (where they are formed) to other parts of the plant is called translocation. It occurs in the part of the vascular tissue known as phloem.
Write differences between arteries and veins.
|1. They carry blood away from the heart.||1. They carry blood towards the heart.|
|2. They carry oxygenated blood, except pulmonary artery.||2. They carry deoxygenated blood, except pulmonary vein.|
|3. They are thick-walled and deeply seated.||3. They are thin-walled and superficially located beneath the skin.|
|4. They lack valves.||4. They have valves to prevent backflow of blood.|
What is dialysis? Explain.
Dialysis is the artificial process of getting rid of waste and unwanted water from the blood by machines. Dialysis machines contain a tank with solution of water, glucose and salt. Patient’s blood is allowed to pass through the solution for the removal of waste. The cleaned blood is pumped back to a vein. The dialysis continues till entire blood has been purified.
Write the differences between RBCs and WBCs.
|1. They are red in colour.||1. They are colourless.|
|2. They have haemoglobin.||2. They lack haemoglobin.|
|3. They help in transport of gases.||3. They help in fighting against germs and infections.|
|4. They are disc-shaped.||4. They have an irregular shape.|
Why is heart known as the pumping organ of the human body?
Heart is the pumping organ of the human body as it continuously acts as a pump for transporting blood to all body parts. Heart pumps carbon dioxide-rich blood to lungs and oxygen-rich blood to the rest of the body.
What is the significance of dividing heart into different chambers?
The division of heart into different chambers ensures that there is no intermixing of oxygenated and deoxygenated blood. This ensures a better efficiency of circulation and transportation of oxygen.
Why is haemoglobin important for the human body?
Haemoglobin binds with oxygen and transports it to all the parts of the body and ultimately to all the cells. It will be difficult to provide oxygen efficiently to all the cells of the body without haemoglobin.
Long Answer Type Questions
Describe the circulation of blood across the heart and the body.
a. Blood circulation starts when the heart relaxes between two heartbeats. Blood goes from both the atria into the ventricles which then expand. The following phase is called ejection period, which is when both ventricles pump the blood into the large arteries.
b. In the systemic circulation, the left ventricle pumps oxygen-rich blood into the main artery (aorta). The blood travels from the main artery to larger and smaller arteries and into the capillary networks. There the blood releases oxygen, nutrients and other important substances and takes up carbon dioxide and waste substances. The blood, which is now low in oxygen, is collected in veins and travels to the right atrium from where it goes into the right ventricle.
c. Now pulmonary circulation starts. The right ventricle pumps blood that carries little oxygen into the pulmonary artery, which transports this blood to the lungs. This is where carbon dioxide is released from the blood into the air contained in the lungs and fresh oxygen enters the bloodstream. When we breathe out, carbon dioxide leaves our body. Oxygen-rich blood travels through the pulmonary vein into the left atrium from where it goes into the left ventricle. The next heartbeat starts a new cycle of the systemic circulation.
Describe the structure of the human heart.
The human heart is of the size of a fist.
- Heart is a triangular shaped organ. It is made up of cardiac muscles and is located between the lungs inside chest cavity. Its lower tip is slightly tilted towards left.
- It beats 72 to 80 times per minute throughout life. It pumps blood to all parts of the body.
- The heart has four chambers. The upper chambers are called auricles (or atria) and the lower two chambers are called ventricles.
- The left chambers are completely separated from right side by a partition called septum to avoid mixing of pure and impure blood. The chambers contain valves which ensure the flow of blood in one direction only.
- The right auricle receives carbon-dioxide rich blood from various parts of the body. The right ventricle pumps the blood to the lungs. Inside lungs, carbon-dioxide is exchanged with oxygen.
- The left auricle receives oxygen-rich blood from the lungs. The left ventricle pumps this blood to the rest of the body.
Explain the excretory system in human beings.
The waste present in the blood has to be removed from the body. A system to filter the waste is required. This is done by the blood capillaries in the kidneys. When blood reaches the two kidneys, it contains both useful and harmful substances.
The useful substances are absorbed back into the blood after filtration in kidneys. The waste dissolved in water is removed as urine. From the kidneys, the urine goes into the urinary bladder through tubes called ureters. It is stored in the bladder and is passed out through the muscular tube called urethra. The kidneys, ureters, urinary bladder and urethra form the excretory system in humans.
What are the methods used by plants to get rid of excretory products?
To get rid of excretory products, plants use the following ways:
- Excess water is lost by transpiration.
- Many plants store waste products in vacuoles of the cells.
- Some waste products are stored in the leaves. They are removed as the leaves fall off.
- Some waste products such as resins and gums are stored, especially in non-functional old xylem.
- Some waste products such as tannins, resins, gums, etc., are stored in bark, thereby removed as it peels off.
- Plants also excrete some waste substances through roots into the soil around them.
- Oxygen is lost while the stomata open for taking in carbon-dioxide.
Sketch a human heart and label the pulmonary artery, right and left atria, right and left ventricles, septa, pulmonary vein and aorta.
Look at the figure given below and answer the following questions.
a. Name the process depicted.
b. Where is this process used in plants?
b. Osmosis is used by plant roots to absorb water and minerals from the soil.
Observe the given figure and write its use.
The above picture is of a stethoscope and it is used by a doctor as a device to amplify the sound of heartbeat.