What happens at the synapse between two neurons?
Synapse is a point of connection where two neurons gets connected or communicated, where one neuron sends information to another target nerve cell. Synapses are electrical or chemical. Electrical is where flow or exchange if ions occurs and in chemical synapse, they communicate using chemical messengers called hormones, or neurotransmitters.
Sensory nerves carry nerve impulses to the axon terminal which releases chemical messengers called neurotransmitters, then they goes through the synapse to reach the dendrite part of another neuron. And, finally these neurotransmitters goes to muscles, glands etc. to carry forward their actions.
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?
How does the electronic configuration of an atom relate to its position in the Modern Periodic Table?
Element X forms a chloride with the formula XCl2, which is a solid with a high melting point. X would most likely be in the same group of the Periodic Table as
(a) Na (b) Mg (c) AI (d) Si
Describe double circulation of blood in human beings. Why is it necessary?
Draw a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 Ω resistor, an 8 Ω resistor, and a 12 Ω resistor, and a plug key, all connected in series.
On what factors does the resistance of a conductor depend?
Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
How is the small intestine designed to absorb digested food?
Why do stars twinkle?
What change will you observe if you test soap with litmus paper (red and blue)?
Explain the following.
(a) Why is the tungsten used almost exclusively for filament of electric lamps?
(b) Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
(c) Why is the series arrangement not used for domestic circuits?
(d) How does the resistance of a wire vary with its area of cross-section?
(e) Why are copper and aluminium wires usually employed for electricity transmission?