Reflex action, Biology

Assignment Help:

REFLEX ACTION -

  • Marshel Hall discovered reflex action. Best & Taylor defined it. Reflex action is functional unit of CNS.
  • It is sudden, immediate involuntary action against external stimuli. In man it is poly-synaptic.
  • If we prick needle on skin, somatic sensory nerves bring impulses to grey matter. Here these are analysed & order is given to muscle by motor nerve.
  • The path from which impulse is passed is reflex arch.
  • Minimum time is consumed in it. It is not under control of brain.

Some common reflex actions are -

1. Coughing

2. Yawning

3. Sneezing

4. Knee-jerk reflex

5. Bleenking of eyes

6. Scratch reflex

EXAMPLE -

1.       Cycling.

2.       Watering of mouth.

3.       Blinking of eyes in sharp light.

4.       Withdrawal of leg in pithed frog.

5.       Flow of bile from gall bladder.

6.       Peristalasis.

7.       Heart beat.

2243_reflex action.png

SIGNIFICANCE -

1. It enables animal to respond immediately to the harmful stimuli so that no harm is caused to it.

2. It gives more time to brain to work.


Related Discussions:- Reflex action

Explain the periapical surgery - endodontic surgery, Explain the Periapical...

Explain the Periapical surgery - Endodontic Surgery a) Curretage 1 b) Root-end ressection 2 c) Root-end preparation 3 d) Root-end filling 4

Ventricular septal defect (vsd), Ventricular Septal Defect (VSD)   In v...

Ventricular Septal Defect (VSD)   In ventricular septal defect there is abnormal communication between right and left ventricle. Anatomically 90 per cent of all VSD are located

Define national iodine deficiency disorder control programme, Define Nation...

Define National Iodine Deficiency Disorder Control Programme (NIDDCP)? The prevalence of iodine deficiency disorders (IDD) are seen more among adolescent's young adults and sc

Explain chlamydia, Explain Chlamydia  A single 1 g dose of azithromycin...

Explain Chlamydia  A single 1 g dose of azithromycin (Zithromax) or 7 days' treatment with a tetracycline are both effective for treatment of uncomplicated urethral or cervical

Comparison between regeneration and embryonic development, Comparison betwe...

Comparison between Regeneration and Embryonic Development By now you must have realized that the procedures of regeneration and embryonic development have several fundamental

Explain homologous and heterologous immunoglobulins, What is the difference...

What is the difference between homologous and heterologous immunoglobulins? Homologous immunoglobulin is the human (from the similar species) immunoglobulin. In case of inocula

Define role of thiamin in the conversion carbohydrate to fat, Define the Ro...

Define the Role of Thiamin in the conversion carbohydrate to fats? Thiamin helps in the initial steps of fatty acid and sterol production. In this way, thiamin also helps co

Coccidioidomycosis, Coccidioidomycosis Coccidioidomycosis is a soil-...

Coccidioidomycosis Coccidioidomycosis is a soil-borne infection of pet, domestic, wild animals and  man. The disease is caused by Coccidioides immitis, a dimorphic fungus wh

How is the lac operon regulated by the sigma factor, 1. Many bacterial gene...

1. Many bacterial genes show adaptive regulation of their transcription. a) How is the lac operon regulated by the sigma factor? b) How is the lac operon regulated by lactose

Classification of habituating drugs, CLASSIFICATION OF HABITUATING DRUGS - ...

CLASSIFICATION OF HABITUATING DRUGS - There are a large number of drugs on which people become dependent. These are classified into 2 main categories - (i) Psychotropic d

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd