Q1. Why is color of blood red? A. Blood has a Pigment known as hemoglobin that gives red color to it.

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1 BAL BHARATI PUBLIC SCHOOL, PITAMPURA, DELHI CLASS 7 NOTES TRANSPORTATION IN PLANTS AND ANIMALS Q1. Why is color of blood red? A. Blood has a Pigment known as hemoglobin that gives red color to it. Q2. What does blood consist of? A. Blood consists of Red blood cells, white blood cells, platelets and plasma. Q3. What is removed along with water as sweat? A. Extra salts are removed along with water as sweat. Q4. What is the function of stethoscope? A. Stethoscope is used by doctors to amplify heart beat so that it can be analysed properly. Q5. What is pulse? A. Throbbing that occurs in arteries due to flowing of blood is called pulse. Q6. Why is transport of materials necessary in a plant or in an animal? A. All organisms need food, water and oxygen for survival. They need to transport all these to various parts of their body. Q7. What are the functions of white blood cells? A. White blood cells fight against the infection or germs in the body, thereby providing immunity. Q8. How is clot formed? A. Clot is produced as an action of platelets during any external injury to prevent excessive loss of blood. Q9.What is the main function of heart? A. Heart is the main pumping organ for blood to be circulated as blood is required to be sent to all the parts of the body so as carry on all the important functions of body. Q10. Why is it necessary to excrete waste products? A. During various activities which are performed within body, certain by products are produced. Some of these products are toxic and are required to be thrown out. Q11. What is transpiration? How is it useful to plants? A. 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 and keeping plant cooler. Q12. What is meant by excretion? A. It is the process of removal of toxic substances from the body. Q13. Why is blood needed by all the parts of the body?

2 A. Blood helps in transport of various material such as, digested food from the intestine, oxygen and carbon dioxide from their respective sites, watses material for excretion. These are to be transported to ensure proper functioning in the body. Q14. Why do plants absorb a large quantity of water from the soil? A. Plants remove lots of water by the process of transpiration. This is why plants require to absorb large quantity of water from the soil. Q15. Differentiate between: 1. arteries and veins Arteries They carry blood away from heart They carry oxygenated blood except pulmonary artery They are thick walled and deeply seated They lack valves Veins They carry blood towards heart. They carry deoxygenated blood except pulmonary vein They are thin walled and superficially located beneath skin They have valves to prevent backflow of blood. 2. atrium and ventricle Atrium They are the upper chambers of heart They receive blood from various body parts They are thin walled 3. RBC and WBC RBC They are red in colour They have hemoglobin They help in transport of gases Ventricle They are the lower chambers of heart. They distribute blood to various parts of the body They are thick walled WBC They are colourless They lack hemoglobin They help in fighting against germs and infection 4. xylem and phloem Xylem It transports water and minerals It has unidirectional movement. Phloem It transports food It has multidirectional movement.

3 Q16. Why do sponges and hydra not have blood? A. Animals such as sponges and hydra do not possess any circulatory system. The water in which they live brings food and oxygen as it enter their body the water carries away waste materials and carbon dioxide as it moves out. Q17. Why valves present in veins? A. Valves are present in veins to prevent backflow of blood in tissues. Q18. Draw the diagram of human heart and label all the parts. A..Q19. Enlist the functions of blood. A. It transports substances like digested food from the small intestine to the other parts. It carries oxygen and carbondioxide to their respective organs and tissues It transports wastes for removal from the body. Q20. Describe the circulation of blood through heart and body. A. The blood vessels (arteries, veins, and capillaries) are responsible for the delivery of oxygen and nutrients to the tissue. Oxygen-rich blood enters the blood vessels through the heart's main artery called the aorta. The forceful contraction of the heart's left ventricle forces the blood into the aorta which then branches into many smaller arteries which run throughout the body. The inside layer of an artery is very smooth, allowing the blood to flow quickly. The outside layer of an artery is very strong, allowing the blood to flow forcefully. The oxygen-rich blood enters the capillaries where the oxygen and nutrients are released. The waste products are collected and the waste-rich blood flows into the veins in order to circulate back to the heart which further goes to lungs for purification.

4 Q21. Name the types of blood vessels and their functions. A. There are three varieties of blood vessels: arteries, veins, and capillaries. During blood circulation, the arteries carry blood away from the heart. The capillaries connect the arteries to veins. Finally, the veins carry the blood back to the heart. Q22. Explain the process of urine formation in man. A. During circulation, blood passes through the kidneys in order to deposit used and unwanted water, minerals, and a nitrogen-rich molecule called urea. The kidneys filter the wastes from the blood, forming a liquid called urine. The kidneys funnel the urine into the bladder along two separate tubes called ureters. The bladder stores the urine until muscular contractions force the urine out of the body through the urethra. Each day, your kidneys produce about 1.5 liters of urine. All of it needs to be removed from your system. This occurs through urination. Q23. Draw a well labeled diagram of human excretory system and discuss the functions of all the parts. A. Q24. Discuss the flow of blood through heart.

5 A. The heart pumps oxygenated blood to the body and deoxygenated blood to the lungs. In the human heart there is one atrium and one ventricle for each circulation, and with both a systemic and a pulmonary circulation there are four chambers in total: left atrium, left ventricle, right atrium and right ventricle. The right atrium is the upper chamber of the right side of the heart. The blood that is returned to the right atrium is deoxygenated (poor in oxygen) and passed into the right ventricle to be pumped through the pulmonary artery to the lungs for re-oxygenation and removal of carbon dioxide. The left atrium receives newly oxygenated blood from the lungs as well as the pulmonary vein which is passed into the strong left ventricle to be pumped through the aorta to the different organs of the body.