Advertisements
Advertisements
प्रश्न
Answer the following question:
What is a reflex action? Explain it with two examples.
उत्तर
Reflex action.
Any sudden action in response to some happening in the environment, without thinking about it or without feeling in control of our reactions is called reflex action.
1. Reflex action
- The sudden action in response to some happenings in the environment is called reflex action.
- It is an involuntary action that we perform automatically.
- The pathway has taken by nerve impulses in a reflex action is called reflex arcs. Reflex arcs allow a rapid response.
- A nerve from all over the body meet in a bundle in such a connection is commonly called as the spinal cord, before impulses are sent to the brain.
- Hence, reflex arcs are formed in the spinal cord, although the messages reach the brain.
Pulling away from our hands-on touching a hot object, narrowing of the eyes in the sunlight, watering of the mouth on smelling something delicious, etc. are examples of reflex action.
APPEARS IN
संबंधित प्रश्न
What is the function of receptors in our body?
Write the names of the indicated parts 1 to 6 in the following diagram:
Fill in the following blank with suitable word :
The neuron which carries a message for action to a muscle or gland is known as a......... neuron.
How does the human nervous system work? Explain.
How are the messages carried across a synapse? Explain with the help of a labelled diagram.
Multiple choice question. Tick (✓) the correct choice:
Nervous system in humans consists of
- brain and nerves
- brain and spinal cord
- brain, spinal cord and nerves
- none of the above
Write one word in the space provided to complete the second pair of the related words pertaining to the nervous system.
Memory: cerebrum:: breathing:
Balance: cerebellum:: reasoning:
Briefly describe the structure of the cerebrum in the human brain, and mention its functions.
Name the following:
The biological term given to the protective membranes of the brain.
Name the parts (a) to (e) in the following diagram.
What is the term given to the sequence of events occurring in the diagram?
Explain the Term: Ganglion
Name the following:
Unit of the nervous system is
Give Technical Term:
The structure which joins the two cerebral hemispheres in man.
The third ventricle of brain is connected to the fourth ventricle of brain through ______.
List out the functions of Endocrine system and Nervous system.
Hypothalamus is the thermoregulatory centre of the human body.
How many pairs of cervical spinal nerves are present in humans?
Identify the match that pairs the nerve correctly with its type.
How many spinal nerves are there, and to which groups they belong?
Think of situations where receptors do not work properly. What problems are likely to arise?