Every question from this NCERT chapter, with a detailed explanation.
With reference to the mode of nutrition in living organisms, consider the following statements: 1. Autotrophic nutrition is the mode where organisms take in food prepared by others. 2. Animals are classified as heterotrophs. 3. The term ‘heterotrophs’ refers to organisms that depend on others for nourishment. Which of the statements given above are correct?
With reference to the cell structure described in the text, consider the following statements: 1. The cell membrane encloses the cell and controls the movement of substances. 2. The nucleus is a jelly-like substance that fills the entire cell. 3. Cytoplasm is the hard outer covering found only in plant cells. Which of the statements given above is/are correct?
Consider the following statements about algae: 1. They are generally formed by the growth of organisms in stagnant water. 2. They appear green because they lack chlorophyll. 3. They are autotrophs and can prepare their own food. Which of the statements given above is/are correct?
Consider the following statements regarding insectivorous plants like the Pitcher plant: 1. They trap insects primarily to obtain carbohydrates. 2. They contain chlorophyll and can perform photosynthesis. 3. The pitcher-like structure is a modified part of the leaf. Which of the statements given above are correct?
With reference to saprotrophic nutrition, consider the following statements: 1. It is a mode of nutrition where organisms take in nutrients from dead and decaying matter. 2. Fungi ingest dead matter directly without secreting digestive juices. 3. All fungi are harmful and cause spoilage of food and diseases. Which of the statements given above is/are correct?
Which of the following pairs is correctly matched regarding the symbiotic relationship in Lichens?
Consider the following statements about the bacterium Rhizobium: 1. It can convert atmospheric nitrogen into a usable soluble form. 2. It can make its own food through photosynthesis. 3. It lives in the roots of leguminous plants like gram and peas. Which of the statements given above is/are correct?
What does the term 'Symbiosis' refer to in ecology?
With reference to the presence of starch in leaves, consider the following statements: 1. The presence of starch in leaves indicates the absence of photosynthesis. 2. Starch is a carbohydrate synthesized by plants. 3. Iodine solution is used to test for the presence of starch. Which of the statements given above are correct?
Consider the following statements regarding leaves with colours other than green (e.g., red, violet, brown): 1. These leaves contain chlorophyll despite their colour. 2. Photosynthesis cannot take place in these leaves. 3. The red and brown pigments destroy the chlorophyll. Which of the statements given above is/are correct?
Consider the following statements about fungal spores: 1. They are generally present in the air. 2. They require dry and cold conditions to germinate. 3. They are the reproductive units of the fungi. Which of the statements given above is/are correct?
Why is nitrogen supplementation often essential for agricultural soil?
Consider the following statements regarding the transport of materials in plants: 1. Water and minerals are primarily absorbed by the leaves. 2. They are transported to the leaves through a continuous path of vessels. 3. The vessels form a continuous path from the roots to the leaves. Which of the statements given above are correct?
With reference to the synthesis of proteins in plants, consider the following statements: 1. Proteins contain nitrogen. 2. Plants absorb nitrogen directly from the air through leaves. 3. Plants can synthesize proteins using only carbon dioxide and water. Which of the statements given above is/are correct?
Which one of the following characteristics describes the plant 'Cuscuta' (Amarbel)?
Consider the following statements regarding the relationship between legumes and Rhizobium: 1. It is an example of a symbiotic relationship. 2. The bacteria provide food and shelter to the plant. 3. The plant provides nitrogen to the bacteria. Which of the statements given above is/are correct?
Through which structure do plants primarily absorb carbon dioxide for photosynthesis?
Consider the following statements about the digestive process in saprotrophs: 1. They digest food externally before ingestion. 2. They secrete digestive juices inside their bodies. 3. They absorb nutrients in solution form. Which of the statements given above is/are correct?
With reference to the role of the sun in nutrition, consider the following statements: 1. Solar energy is primarily captured by the roots of the plant. 2. Solar energy is stored in the plant in the form of food. 3. Photosynthesis converts solar energy into chemical energy. Which of the statements given above is/are correct?
What is the fundamental difference between a parasitic and a saprotrophic mode of nutrition?
Consider the following statements regarding the iodine test on leaves: 1. It is primarily used to detect the presence of chlorophyll in leaves. 2. A blue-black colour indicates the presence of starch. 3. Leaves kept in the dark for a few days turn blue-black when tested. Which of the statements given above is/are correct?
Why do insectivorous plants, such as the Pitcher plant, trap and digest insects?
Consider the following statements about the structure of a cell: 1. The nucleus is usually spherical and located in the centre of the cell. 2. The cytoplasm is a hard, solid substance between the nucleus and membrane. 3. The cell membrane encloses the cell and regulates movement of substances. Which of the statements given above is/are correct?
Which group of organisms is primarily responsible for the mold growth observed on bread under humid conditions?
Which one of the following crops is a legume capable of symbiotic nitrogen fixation via Rhizobium?
Consider the following statements regarding the function of stomata: 1. They allow the direct intake of nitrogen from the atmosphere. 2. They are involved in the release of oxygen during photosynthesis. 3. They facilitate the loss of water in the form of vapour. Which of the statements given above is/are correct?
In the morphology of a Pitcher plant, what is the function of the leaf modification that forms a 'lid'?
Consider the following statements about nutrients: 1. Carbohydrates, proteins, fats, vitamins, and minerals are components of food. 2. These components are collectively known as roughage. 3. Only animals require these nutrients, while plants do not. Which of the statements given above is/are correct?
Match List I with List II and select the correct answer using the code given below: List I | List II A. Cuscuta | 1. Autotrophic B. Mushroom | 2. Saprotrophic C. Pitcher Plant | 3. Parasitic D. Algae | 4. Insectivorous
Consider the following statements about the transport system in plants: 1. Roots absorb water and minerals from the soil. 2. The transport vessels are restricted to the roots and do not reach the stem. 3. The vessels form a continuous network reaching the leaves. Which of the statements given above is/are correct?
Consider the following statements regarding the mode of nutrition in humans: 1. Humans are autotrophs capable of synthesizing their own food. 2. Humans depend on plants and and other animals for food. 3. Humans are classified as heterotrophs. Which of the statements given above is/are correct?
Which of the following pairs is correctly matched?
What is the primary function of 'guard cells' in plant physiology?
What accounts for the characteristic green colour of algae?