Phototropism Geotropism Hydrotropism Thigmotropism_Unsolved paper
Chapter: Control and Coordination | Topic: Phototropism Geotropism Hydrotropism Thigmotropism
PHOTOTROPISM GEOTROPISM HYDROTROPISM THIGMOTROPISM_UNSOLVED PAPER
Topic: Phototropism Geotropism Hydrotropism Thigmotropism
Q1. The growth of a plant shoot towards sunlight is called:
- Geotropism
- Hydrotropism
- Phototropism
- Thigmotropism
Q2.Roots growing downward into the soil mainly show:
- Positive geotropism
- Negative geotropism
- Positive phototropism
- Negative hydrotropism
Q3.The movement of roots towards a source of water is known as:
- Chemotropism
- Phototropism
- Hydrotropism
- Thigmotropism
Q4.Which type of tropic movement helps pea plants and grapevines climb around a support?
- Phototropism
- Hydrotropism
- Geotropism
- Thigmotropism
Q5.A potted plant kept near a classroom window bends towards the incoming sunlight after a few days. This is an example of:
- Geotropism
- Hydrotropism
- Phototropism
- Thigmotropism
Q6.Which plant hormone mainly helps in bringing about tropic movements?
- Ethylene
- Ethylene
- Cytokinin
- Abscisic acid
Short questions
Q1. Define phototropism. Give one example from everyday life.
Q2. Differentiate between positive geotropism and negative geotropism.
Q3. Explain hydrotropism with the help of a suitable example.
Q4. What is thigmotropism? Why is it beneficial for climbing plants?
Q5. A farmer notices that plant roots spread towards a moist area after irrigation. Identify the type of tropic movement involved and explain the observation.
Q6. How does auxin help plant shoots bend towards sunlight?
Q1. Describe phototropism, geotropism, hydrotropism, and thigmotropism. Give one suitable example of each and explain their importance in plant survival.
Q2.Draw a neat and labelled diagram showing a plant exhibiting phototropism. Explain how unequal distribution of auxin causes the shoot to bend toward light.
Q3.A gardener plants money plants near a wall and places flowering plants close to a sunny window. Explain how different tropic movements help these plants grow successfully. Mention the role of at least three different tropic responses.
Q1. A biology teacher observed the growth direction of 50 seedlings in a classroom experiment.
Answer the following:
How many seedlings showed phototropism and geotropism together?
Calculate the percentage of seedlings showing hydrotropism.
Which tropic movement was observed in the least number of seedlings?
Suggest one reason why phototropism was observed more frequently in this experiment.
Q2. A student measured the length of a plant shoot placed near a window for five consecutive days.
Answer the following:
Calculate the total increase in shoot length.
Calculate the average daily increase in length.
On which day was the maximum height recorded?
Explain one environmental factor responsible for the direction of growth.
Q3.Read the following situation carefully:
A science club conducted an experiment using four identical potted plants.
Plant A was kept near a sunny window.
Plant B was placed horizontally on the ground.
Plant C was kept in soil where water was supplied from only one side.
Plant D was provided with a vertical stick for support.
Based on the observations, answer the following:
Identify the type of tropic movement expected in Plant A.
Which plant is likely to show hydrotropism?
Which plant is expected to show thigmotropism?
Which plant demonstrates geotropism most clearly?
Explain how these responses help plants survive in natural conditions.