A. Choose the correct option
- A. Choose the correct option
1. Which of these allow blood to flow through them?
a. Arteries
b. Veins
c. Capillaries
d. All of these
Answer: d. All of these
2. What are contractions and relaxations of heart muscles called?
a. Heart beat
b. Pulse
c. Capillaries
d. Ventricles
Answer: a. Heart beat
3. Which of these carries oxygenated blood from the lungs to the heart?
a. Pulmonary artery
b. All arteries
c. Pulmonary vein
d. All veins
Answer: c. Pulmonary vein
4. Which of these needs to get transported within a plant body?
a. Water and minerals
b. Wastes
c. Manufactured food
d. All of these
Answer: d. All of these
5. Which of these stores urine till it is released?
a. Kidneys
b. Urinary bladder
c. Urethra
d. None of these
Answer: b. Urinary bladder
B. Fill in the blanks with the correct words
- The circulatory (transport/excretory) system in humans is made up of blood, blood vessels, and heart.
- Wastes get removed from the cells and the body by a special process called excretion (respiration/excretion).
- A fluid called blood flows inside pipelines called blood vessels (blood vessels/blood cells).
- The pulmonary artery (artery/vein) carries blood from the heart to the lungs.
- Kidneys are made up of tiny filtering units called nephrons (capillaries/nephrons).
- Xylem (Xylem/Phloem) carries water and minerals from the root to the stem to the leaves.
C. Write T for True and F for False
- Many waste materials get produced as a result of various chemical reactions that take place within the living body. – True
- Capillaries are the thickest blood vessels and help to pump blood to all parts of the body. – False
- The blood vessels contract and relax to pump blood into the veins. – False
- The right ventricle opens into the left ventricle and the right auricle opens into the left auricle. – False
- Water gets continuously lost from the leaves by the process of transpiration. – True
- Carbon dioxide is formed as a result of photosynthesis in plants and gets released from the body through the stomata. – False
D. Answer the following questions
1. List the different kinds of substances that need to be transported within a living body.
In a living body, several important substances need to be transported. These include food, oxygen, water, and minerals that are required by cells for energy and growth. Waste materials like carbon dioxide and urea also need to be carried away for removal. This transportation ensures that every part of the body functions properly and remains healthy.
2. Name the three kinds of blood vessels found in humans.
There are three main kinds of blood vessels in the human body—arteries, veins, and capillaries. Arteries carry blood away from the heart to different body parts, while veins bring blood back to the heart. Capillaries are tiny, thin blood vessels that connect arteries and veins and help exchange oxygen, nutrients, and waste between the blood and body cells.
3. Differentiate between arteries and veins.
| S.No. | Arteries | Veins |
| 1. | Arteries carry blood away from the heart. | Veins carry blood toward the heart. |
| 2. | They carry oxygenated blood, except the pulmonary artery. | They carry deoxygenated blood, except the pulmonary vein. |
| 3. | The walls of arteries are thick and elastic to bear high pressure. | The walls of veins are thin and less elastic. |
| 4. | Arteries do not have valves. | Veins have valves to prevent the backflow of blood. |
| 5. | Blood in arteries flows with high pressure. | Blood in veins flows with low pressure. |
4. What is the circulatory system? Name the main organs of the human circulatory system.
The circulatory system is the network that transports blood, oxygen, and nutrients throughout the body. It also removes waste materials like carbon dioxide. The main organs of the circulatory system are the heart, blood, and blood vessels. The heart acts as a pump, blood carries substances, and blood vessels form pathways for blood to travel to and from different parts of the body.
5. What is blood? What is it made up of?
Blood is a red-colored fluid that circulates in our body and transports oxygen, nutrients, and wastes. It is made up of plasma, red blood cells (RBCs), white blood cells (WBCs), and platelets. Plasma is the liquid part, RBCs carry oxygen, WBCs fight diseases, and platelets help in clotting. Together, these components keep the body healthy and functioning properly.
6. What is pulse?
A pulse is the regular rhythmic beating felt in arteries when the heart pumps blood through them. It can be felt in places like the wrist or neck. The pulse rate tells how many times the heart beats per minute. It usually increases during exercise or excitement and decreases during rest. The pulse helps doctors check heart health and blood circulation.
7. Name the four chambers of the heart.
The human heart has four chambers—right auricle, right ventricle, left auricle, and left ventricle. The right auricle receives impure blood from the body and sends it to the right ventricle, which pumps it to the lungs for oxygen. The left auricle receives oxygenated blood from the lungs and passes it to the left ventricle, which pumps it to the rest of the body.
8. List the various things that need to be transported within a plant body.
In plants, several substances need to be transported. Water and minerals absorbed by roots are carried to the leaves, and the food prepared in leaves through photosynthesis is transported to other parts of the plant. This movement takes place through xylem and phloem tissues. Xylem carries water and minerals, while phloem carries food to all growing and storage parts.
9. Differentiate between xylem and phloem.
Xylem and phloem are plant tissues that help in transportation. Xylem carries water and minerals from the roots to the stem and leaves, while phloem carries prepared food from the leaves to other parts of the plant. Xylem moves materials in one direction (upward), but phloem can move food both upward and downward. Together, they maintain nourishment and growth in plants.
10. Define excretion. Name the main organs of the human excretory system.
Excretion is the process through which the body removes harmful waste materials produced by cells. The main organs of the human excretory system are the kidneys, ureters, urinary bladder, and urethra. Kidneys filter blood to remove waste and extra water, forming urine. The urine passes through the ureters to the urinary bladder, where it is stored before being released through the urethra.
11. What are the wastes that get created inside an animal body?
Inside an animal body, many wastes are produced during different life processes. The primary waste products are carbon dioxide, urea, sweat, and water. Carbon dioxide is formed during respiration, while the breakdown of proteins produces urea. Sweat removes extra water and salts. These wastes must be removed regularly to keep the body clean and prevent harmful effects on health.
12. How does the human body get rid of its wastes?
The human body removes wastes in several ways. Carbon dioxide is removed through breathing, while urea and extra water are excreted through urine by the kidneys. Sweat glands in the skin remove salts and water as sweat. The liver also helps in breaking down harmful substances. All these processes together help maintain balance and keep the body healthy and clean.
13. Name any three wastes excreted by plants.
Plants also produce wastes during their life processes. Some common wastes are oxygen, gums, and resins. Oxygen is released during photosynthesis through tiny pores called stomata. Gums and resins are stored in old parts of the plant like bark and help get rid of toxic substances. Some plants also release excess water through a process called transpiration.