Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials (Water, Carbon dioxide and sunlight) must reach there. Water and minerals are transported to the leaves by the vessels which run like pipes throughout the root, the stem, the bRead more
Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials (Water, Carbon dioxide and sunlight) must reach there. Water and minerals are transported to the leaves by the vessels which run like pipes throughout the root, the stem, the branches and the leaves. The leaves have a green pigment called chlorophyll which helps leaves to capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water.
• Take a potted plant with variegated leaves – for example, money plant or crotons. • Keep the plant in a dark room for three days so that all the starch gets used up. • Now select a leaf cover its portion with a black strip paper and keep the plant in sunlight for about six hours. • Pluck the leafRead more
• Take a potted plant with variegated leaves – for example, money plant or crotons.
• Keep the plant in a dark room for three days so that all the starch gets used up.
• Now select a leaf cover its portion with a black strip paper and keep the plant in sunlight for about six hours.
• Pluck the leaf from the plant. Mark the uncovered area in it and trace them on a sheet of paper.
• Dip the leaf in boiling water for a few minutes.
• After this, immerse it in a beaker containing alcohol.
• Carefully place the above beaker in a water-bath and heat till the alcohol begins to boil.
• Now dip the leaf in a dilute solution of iodine for a few minutes.
• Take out the leaf and rinse off the iodine solution.
• You observe that the presence of starch in various areas of the leaf which was uncovered.
All organisms need to take food to get energy for the growth, development and maintenance of their bodies. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
All organisms need to take food to get energy for the growth, development and maintenance of their bodies.
Fill in the blanks: Green plants are called _________________ since they synthesise their own food.
Green plants are called autotrophs since they synthesise their own food. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
Green plants are called autotrophs since they synthesise their own food.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
See lessGive a brief description of the process of synthesis of food in green plants.
Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials (Water, Carbon dioxide and sunlight) must reach there. Water and minerals are transported to the leaves by the vessels which run like pipes throughout the root, the stem, the bRead more
Leaves are the food factories of plants. The synthesis of food in plants occurs in leaves. Therefore, all the raw materials (Water, Carbon dioxide and sunlight) must reach there. Water and minerals are transported to the leaves by the vessels which run like pipes throughout the root, the stem, the branches and the leaves. The leaves have a green pigment called chlorophyll which helps leaves to capture the energy of the sunlight. This energy is used to synthesise (prepare) food from carbon dioxide and water.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
See lessHow would you test the presence of starch in leaves?
• Take a potted plant with variegated leaves – for example, money plant or crotons. • Keep the plant in a dark room for three days so that all the starch gets used up. • Now select a leaf cover its portion with a black strip paper and keep the plant in sunlight for about six hours. • Pluck the leafRead more
• Take a potted plant with variegated leaves – for example, money plant or crotons.
• Keep the plant in a dark room for three days so that all the starch gets used up.
• Now select a leaf cover its portion with a black strip paper and keep the plant in sunlight for about six hours.
• Pluck the leaf from the plant. Mark the uncovered area in it and trace them on a sheet of paper.
• Dip the leaf in boiling water for a few minutes.
• After this, immerse it in a beaker containing alcohol.
• Carefully place the above beaker in a water-bath and heat till the alcohol begins to boil.
• Now dip the leaf in a dilute solution of iodine for a few minutes.
• Take out the leaf and rinse off the iodine solution.
• You observe that the presence of starch in various areas of the leaf which was uncovered.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
See lessWhy do organisms need to take food?
All organisms need to take food to get energy for the growth, development and maintenance of their bodies. https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
All organisms need to take food to get energy for the growth, development and maintenance of their bodies.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-1/
See less