Advertisements
Advertisements
Questions
What is a reflex action?
What is meant by Reflex action?
Advertisements
Solution 1
Reflex action is a sudden, spontaneous, automatic, involuntary response to a stimulus.
Solution 2
Reflex action is an autonomic, quick and involuntary action in the body brought about by a stimulus.
APPEARS IN
RELATED QUESTIONS
How do we detect the smell of an agarbatti (incense stick)?
With the help of a neat and labelled diagram, describe reflex arc.
Name the function of cerebrum.
The contraction of pupil of the eye in the presence of bright light is an example of :
(a) Voluntary reflex
(b) Spinal reflex
(c) Cerebral reflex
(d) Adrenal reflex
A cylindrical structure P in our body begins in continuation with medulla and extends downwards. It is enclosed in a bony cage Q and surrounded by membranes R. As many as x pairs of nerves arise from the structure P. The structure P is involved in the reflex actions of our body and conduction of nerve impulses to and from another organ S of our body with which it forms CNS.
(a) Name the structure P.
(b) Name (i) bony cage Q, and (ii) membranes R.
(c) How much is x?
(d) Name the organs S.
(e) What are the reflexes involving structure P only known as?
Differentiate between the following pair of terms:
Stimulus and impulse
Multiple choice question. Tick (✓) the correct choice:
Reflex actions occur under the control of
- brain
- medulla oblongata
- spinal cord
- cerebrum
what do we refer to in the nervous system when we say:
Natural and conditioned …………………
State whether the following is simple reflex, conditioned reflex or neither of the two:
Sneezing: …………….
State whether the following is simple reflex, conditioned reflex or neither of the two.
Blushing
State whether the following is
Cleaning
State whether the following is
Playing on the Keyboard
State whether the following is
Salivation when food is put in the mouth.
What type of reflex is the following?
Sweating in summer
Give Technical Term:
The scientist, who conducted experiment on a dog to show conditioned reflex
Reflex actions are mediated through ____________.
The given diagrammatic representation of reflex action shows knee jerk reflex.

Identify the parts labeled as A to E and select the correct option.
Why have reflex arcs evolved in animals?
The diagram given below shows the internal structure of a spinal cord depicting a phenomenon. Study the diagram and answer the following questions.
![]() |
- Name the phenomenon shown in the figure and define the same.
- Identify the parts labelled as 1 and 2. Write one functional difference between these two.
- Name the bony protective covering and the membranous protective covering of the spinal cord.
- Label the guidelines 3 and 4.
- How is the labelled part 3 different from part 4 with respect to its composition (part of neuron)?
- Give the technical term for the point of contact between the two nerve cells.
- Name the fluid filled inside the central canal of spinal cord.
- Name the term used for a small gap between two neurons.
- Give one example of a neurotransmitter.
- Draw a neat diagram of a nerve cell and label the parts: Perikaryon, Node of Ranvier, Myelin sheath and Axon terminals.

