How is the movement of leaves of the sensitive plant different from the movement of a shoot towards light?
The movement of leaves of the sensitive plants shows the bending or drooping of leaves when they being touched by someone and they doesn't show any growth pattern in them.
On the other hand, the movement of shoot towards light shows the process of phototropism which is unidirectional & shows the growth pattern.
Draw the structure of a neuron and explain its function.
Which signals will get disrupted in case of a spinal cord injury?
How does chemical coordination take place in animals?
Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.
Why is the use of iodised salt advisable?
The brain is responsible for
(a) thinking.
(b) regulating the heart beat.
(c) balancing the body.
(d) all of the above.
How do we detect the smell of an agarbatti (incense stick)?
How do auxins promote the growth of a tendril around a support?
Which part of the brain maintains posture and equilibrium of the body?
How does our body respond when adrenaline is secreted into the blood?
Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
What is a good source of energy?
Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?
What are trophic levels? Give an example of a food chain and state the different trophic levels in it.
What changes can you make in your habits to become more environment-friendly?
What is the importance of DNA copying in reproduction?
If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?
Why should a magnesium ribbon be cleared before burning in air?
Define the principal focus of a concave mirror.
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
What could be the reasons for adopting contraceptive methods?
Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.
Compare the above system with the probable systems in hilly/mountainous areas or plains or plateau regions.
An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.
Name the type of mirror used in the following situations.
(a) Headlights of a car.
(b) Side/rear-view mirror of a vehicle.
(c) Solar furnace.
Support your answer with reason.
An electric oven of 2 kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.
Why are we looking at alternate sources of energy?
What is the far point and near point of the human eye with normal vision?
Why is the amount of gas collected in one of the test tubes in Activity 1.7 double of the amount collected in the other? Name this gas.
Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?