Chapter 7 Transportation in Animals and Plants
1. Match structures given in Column I with functions given in Column II.
Column I Column II
(i) Stomata (a) Absorption of water
(ii) Xylem (b) Transpiration
(iii) Root hairs (c) Transport of food
(iv) Phloem (d) Transport of water
(e) Synthesis of carbohydrates
Ans:
| Column I | Column II |
|---|---|
| (i) Stomata | (b) Transpiration |
| (ii) Xylem | (d) Transport of water |
| (iii) Root hairs | (a) Absorption of water |
| (iv) Phloem | (c) Transport of food |
| (e) Synthesis of carbohydrates | Not listed in Column II (primarily occurs in leaves) |
2. Fill in the blanks.
(i) The blood from the heart is transported to all parts of the body by
the ________________ .
Ans: arteries.
(ii) Haemoglobin is present in _______________ cells.
Ans : red blood cells.
(iii) Arteries and veins are joined by a network of __________________.
Ans: capillaries.
(iv) The rhythmic expansion and contraction of the heart is called_______________.
.Ans: cardiac cycle.
(v) The main excretory product in human beings is ________________ .
vi) Sweat contains water and ____________.
Ans: several other substances.
(vii) Kidneys eliminate the waste materials in the liquid form called_______________.
Ans: urine.
viii) Water reaches great heights in the trees because of suction pull
caused by ______________.
3. Choose the correct option:
(a) In plants, water is transported through
(i) xylem (ii) phloem
(iii) stomata (iv) root hair
Ans: (i) xylem
(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
Ans: (iii) under the fan
4. Why is transport of materials necessary in a plant or in an animal?
Explain.
Ans: Transport of materials is essential for both plants and animals because it allows them to carry out vital functions necessary for survival. Here's a breakdown of why it's crucial:
In Plants:
- Delivering Nutrients and Water: Plants absorb water and minerals through their roots. These materials need to be transported throughout the plant to reach all cells. Xylem, a specialized vascular tissue, transports water and dissolved minerals from the roots to the leaves and other parts of the plant.
- Distributing Food: Plants manufacture food (sugars) through photosynthesis, primarily in their leaves. This food needs to be transported to all parts of the plant for growth, energy production, and storage. Phloem, another vascular tissue, transports food (sugars) from the leaves to other parts of the plant.
- Maintaining Balance: Plants lose water vapor through transpiration, primarily from their leaves. To maintain water balance, they need to constantly take up water from the soil to replace what's lost.
In Animals:
- Supplying Cells with Oxygen: Animal cells require oxygen for cellular respiration, the process that generates energy. The respiratory system takes in oxygen from the environment, and the circulatory system (blood vessels and heart) transports oxygen to all the cells in the body.
- Delivering Nutrients: Animals obtain nutrients from the food they eat. The digestive system breaks down food into smaller molecules, and the circulatory system transports these absorbed nutrients to all the body's cells for various functions like growth, repair, and energy production.
- Removing Waste Products: Cellular activities produce waste products like carbon dioxide. The circulatory system transports these wastes to organs like the lungs and kidneys for elimination from the body.
Overall, the transport system in plants and animals is like a complex delivery network. It ensures that essential materials reach all parts of the organism, allowing them to function properly and survive.
5. What will happen if there are no platelets in the blood?
Ans: If there are no platelets in the blood, a serious condition called thrombocytopenia arises. Here's what would happen:
Uncontrolled Bleeding: Platelets are crucial for blood clotting. When there are none, even minor injuries will lead to prolonged bleeding because there wouldn't be any mechanism to form clots and seal the wound.
Excessive Blood Loss: This uncontrolled bleeding can lead to significant blood loss, which can deprive tissues and organs of oxygen and nutrients.
Complications: Depending on the severity of blood loss, complications like dizziness, weakness, fatigue, and even shock can occur. In extreme cases, uncontrolled bleeding can be life-threatening.
Internal Bleeding: The lack of platelets also increases the risk of internal bleeding, which can be harder to detect and even more dangerous.
Causes of No Platelets:
Several factors can lead to a low platelet count, including:
- Bone marrow problems: Diseases or conditions affecting bone marrow, the site of platelet production, can reduce platelet production.
- Increased Platelet Destruction: Certain medications, infections, or autoimmune diseases can destroy platelets faster than they're produced.
- Spleen Issues: An enlarged spleen can trap platelets, reducing their circulation in the bloodstream.
Treatment:
Treatment for no platelets depends on the underlying cause. It may involve medications to stimulate platelet production, blood transfusions with platelets, or treatments to address the cause of platelet destruction.
In summary, having no platelets in the blood is a serious condition that can lead to uncontrolled bleeding, blood loss complications, and even death. Early diagnosis and treatment are crucial to prevent these risks.
6. What are stomata? Give two functions of stomata.
Ans: Stomata are tiny pores, usually located on the underside of leaves, that allow for gas exchange between the plant and the environment. They function like microscopic valves that open and close in response to various environmental factors. Here are two crucial functions of stomata:
Gas Exchange: Stomata allow plants to take in carbon dioxide (CO2) from the surrounding air, which is necessary for photosynthesis, the process by which plants produce their own food (glucose) using sunlight. At the same time, stomata allow oxygen (O2), a byproduct of photosynthesis, to be released into the atmosphere.
Water Regulation: Stomata also play a vital role in regulating water loss through transpiration, the process by which plants release water vapor into the atmosphere. By opening and closing stomata, plants can control the amount of water vapor released. When there's plenty of water available, stomata may stay open to allow for gas exchange. However, during dry periods or when water is scarce, stomata close to minimize water loss through transpiration.
In essence, stomata act as a delicate balancing act, allowing plants to take in the CO2 they need for food production while regulating water loss through transpiration.
7. Does transpiration serve any useful function in the plants? Explain.
Ans: Yes, transpiration, while involving water loss, serves several useful functions in plants:
Cooling Effect: Transpiration helps regulate plant temperature. As water evaporates from the surface of leaves through stomata, it absorbs heat from the surrounding plant tissue. This process helps prevent plants from overheating, especially in hot and dry environments. Imagine sweating in humans; it's a similar cooling mechanism.
Nutrient Uptake: The transpiration pull created by stomata opening creates a suction force that draws water and dissolved minerals from the roots up the xylem (vascular tissue) to the leaves. This constant water movement is essential for nutrient delivery throughout the plant.
Think of it like a straw pulling up a drink. As water evaporates from the top (leaves), it pulls more water up from the bottom (roots) through the straw (xylem).
- Structural Support: Transpiration also contributes to the structural support of plants, especially tall trees. The tension created by the water column within the xylem helps provide rigidity and keeps the plant upright.
Imagine a standing water hose; the water inside provides some structural support. In a similar way, the water column in the xylem helps support tall trees.
So, while water loss through transpiration might seem like a disadvantage, it's a necessary process for plant survival and function. The benefits of cooling, nutrient transport, and structural support outweigh the water loss. Plants have adapted mechanisms like stomatal control to regulate transpiration and minimize water loss when needed.
Blood Circulation: The heart's rhythmic contractions generate a force that pushes blood through a vast network of arteries, veins, and capillaries. This continuous flow ensures that all your organs and tissues receive the nourishment they need.
Oxygenated Blood Delivery: After picking up fresh oxygen from the lungs, blood travels to the left atrium of the heart. From there, it gets pumped to the left ventricle, the heart's strongest chamber, and then out to the body via the aorta, the largest artery.
Deoxygenated Blood Removal: Blood depleted of oxygen returns from the body to the right atrium of the heart. It then flows to the right ventricle and gets pumped back to the lungs for re-oxygenation, completing the cycle.
In essence, the heart works like a double pump, ensuring a constant supply of oxygen-rich blood reaches all parts of your body while removing waste products like carbon dioxide.
- Cellular Activities: Throughout the day, our cells are constantly working to keep us alive. This internal machinery produces byproducts we don't need, like carbon dioxide and urea.
- Toxic Build-up: If these waste products weren't removed, they would accumulate in our bodies. This build-up would be poisonous and damage our cells and organs.
- Excretion to the Rescue: Thankfully, our bodies have a sophisticated system to eliminate these harmful wastes. We excrete them through various organs like the lungs (carbon dioxide), kidneys (urea in urine), skin (sweat), and even the digestive system (feces).
By getting rid of these waste products, excretion helps maintain a healthy internal environment for our cells to function properly.
Ans:
1. Find out about blood groups and their importance.
Ans: There are 4 main blood groups defined by the ABO system: blood group A – has A antigens on the red blood cells with anti-B antibodies in the plasma. blood group B – has B antigens with anti-A antibodies in the plasma. blood group O – has no antigens, but both anti-A and anti-B antibodies in the plasma.
2. 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.
Ans:
