Activity To Show Hydrotropism In Plants' title='Activity To Show Hydrotropism In Plants' />Teachers notes FOURPAGE FORMAT continued Student page 3 The third student page provides a handson activity. It may be an experiment, art or craft activity. Lakhmir Singh Biology Class 1. Solutions Control and Coordination. Lakhmir Singh Biology Class 1. Solutions Page No 9. Question 1 What is the general name of chemical substances which bring about control and coordination in plants Solution Phytohormones. Question 2 Which plant hormone is responsible for the wilting and falling of leaves From the very beginnings, attempts to identify mechanisms underlying polar auxin transport in higher plants have been intimately linked to studies on the regulation. Solution Abscisic acid is responsible for the wilting and falling of leaves in plants. Question 3 Which plant hormone makes a stem or shoot bend towards light Solution Auxin. Question 4 Where is the auxin hormone made in a plant stem Solution Auxin is made at the tip of the plant stem. Question 5 What is the scientific name of sensitive plant Solution Mimosa pudica. Question 6 Name one plant hormone that promotes growth and another plant hormone which inhibits growth. Solution A plant hormone that promotes growth is Gibberellin and the hormone that inhibits growth is abscisic acid. Question 7 Name one example of the movement of a plant part which is very quick and can be observed easily. Solution Thigmonastic movement in the leaves of touch me not plant is very quick and can be observed easily. Question 8 Name the type of chemical substances that control the growth in plants. Solution Phytohormones. Question 9 What is the stimulus in a phototropism Solution a Light. Gravity. c Chemical. Water. e Touch. Question 1. Give the scientific terms used to represent the following a Bending of a shoot towards light. Growing of roots towards the earth. Growth of a pollen tube towards ovule. Bending of roots towards water. Winding of tendril around a support. Solution a Phototropism. Geotropism. c Chemotropism. Hydrotropism. e Thigmotropism. Lakhmir Singh Biology Class 1. Solutions Page No 9. Question 1. 1 Give one example of the movement of a plant part which is caused by the loss of water or migration of water. Solution Thigmonasty. Question 1. 2 Give one example each of a plant part a which is positively hydrotropic as well as positively geotropic. Solution a Root. b Stem. Question 1. 3 Which of the following is a growth movement and which is not a folding up of leaves of sensitive plant on touching with hand. Solution a is not growth movement whereasb is growth movement. Question 1. 4 Name the plant part a which bends in the direction of gravity but away from lightb which bends towards light but away from the force of gravity. Solution a Root. b Stem. Question 1. 5 To which directional stimuli do a roots respond b shoots respond Solution a Gravity. Light. Question 1. Fill in the following blanks a A plants response to light is called. A plants response to gravity is called. Plant shoot grows upward in response to. Plant roots grow downward in response to. Tendrils wind around a support in response tof Plant roots grow towards. A root of a plant grows downward. This is known as. The response of leaves to the sunlight is calledSolution a Phototropism. Geotropism. c Light. Gravity. e Touch. Earth, gravity. g Geotropism. Auxin. i Photonasty. Question 1. 7 Plant parts show two types of movements, one dependent on growth and the other independent of growth. Give one example of the movement in plant parts which depends on growthwhich does not depend on growth. Solution a Bending of stem towards light. Folding up of leaves of a sensitive plant on touching. Question 1. 8 What is a plant hormone Name four plant hormones. State one function of each. Solution The hormones that control and coordinate the activities in plants are called plant hormones. The four types of plant hormones are i Auxins It promotes cell enlargement and cell differentiation in plants. Gibberellines It helps in breaking the dormancy in seeds and buds. Cytokinins It promotes cell division in plants. Abscisic acid It promotes the dormancy in seeds and buds. Question 1. 9 a What does a root do in response to gravity What is this phenomenon known as b What does a stem or shoot do in response to light What is this phenomenon known as Solution a Root bends downwards in the direction of gravity positive geotropism. Stem bends towards the light positive phototropism. Question 2. 0 a What does a stem or shoot do in response to gravity What is this phenomenon known as b What does a root do in response to light What is this phenomenon known as Solution a Stem grows upward against the direction of gravity negative geotropism. Root bends away from light negative phototropism. Question 2. 1 a What does a Mimosa pudica plant do in response to touch What is this phenomenon known as b What happens to the dandelion flower z during daytime, and ii at night What is this phenomenon known as Solution a In Mimosa pudica plant, the leaves fold up in response to touch. This phenomenon is known as thigmonasty. A dandelion flower opens up in the morning in bright light. This phenomenon is known is positive photonasty. Chinese English Dictionary Online Free Download here. At night, the dandelion flower closes and this phenomenon is known as negative photonasty. Question 2. 2 a What does a plant root do in response to water What is this phenomenon known as b What happens to the moonflower i during daytime, and ii at night What is this phenomenon known as Solution a The plant root grows towards water and the phenomenon is known as the hydrotropism. During the daytime the petals of moon flower close when there is bright light. At night, when it is dark the petals of moon flower opens up. This phenomenon is known as photonasty. Question 2. 3 What is a tendril Name the two types of tendrils. What does a tendril do in response to the touch of a support What is this phenomenon known as Solution Tendrils are the thin, thread like growths on the stems or leaves of climbing plants. The two types of tendrils are stem tendrils and leaf tendrils. The tendrils grow towards the things they happen to touch. This phenomenon is known as thigmotropism. Question 2. 4 Name the five types of tropisms. How are tropic movements helpful to plants Explain with an example. Solution The five types of tropisms are Phototropism, Geotropism, Chemotropism, Hydrotropism and Thigmotropism. The various types of tropic movements help the plants to survive. Example even if a seed is planted upside down, its root will grow downwards into earth because it is positively geotropic. Question 2. 5 Define chemotropism. Give one example of chemotropism. State whether this example is of positive chemotropism or negative chemotropism. Solution The growth of a plant part due to chemical stimulus is known as chemotropism. For example the growth of pollen tube towards the ovule induced by a sugary substance as stimulus. This is an example of positive chemotropism. Question 2. 6 Distinguish between tropic movements and nastic movements in plants. Give examples to illustrate your answer. Solution Tropic movements. These movements are always in the direction of the stimulus. These movements are slow. These movements are exhibited by all parts of a plant. For example, movement of shoot towards the light and not towards gravity. Nastic movements. These movements are neither away nor towards the stimulus. These movements are fast. These movements are exhibited by the flat organs like leaves and petals of flowers of a plant. For example, the bending and drooping of leaves in Touch me not plant. Question 2. 7 a What is meant by nastic movements in plants Give one example of nastic movements in plants.