What is the difference between a reflex action and walking?
Reflex action:- reflex action is a involuntary mechanism, spontaneous, automatic, rapid and mechanical response to the external stimuli on specific receptor without the will of an organism. eg. beating of heart, blinking of eyes, upward and downward movement of diaphragm during respiration.
Walking:- walking is a voluntary mechanism, slower than involuntary mechanism, occurs with the will of an organism. It requires brain involvement which sends the electrical signals to various body parts for the movement.
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?
How does our body respond when adrenaline is secreted into the blood?
Which part of the brain maintains posture and equilibrium of the body?
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 criteria do we use to decide whether something is alive?
Explain the following terms with one example each.
(a) Corrosion
(b) Rancidity
Define the unit of current.
Why do ionic compounds have high melting points?
Name a device that helps to maintain a potential difference across a conductor.
What are the differences between the transport of materials in xylem and phloem?
Can the wing of a butterfly and the wing of a bat be considered homologous organs? Why or why not?
Why is sodium kept immersed in kerosene oil?
What are the different methods of contraception?
Define the principal focus of a concave mirror.