Photoperiodism, Biology

Assignment Help:

Photoperiodism

Activity like breeding and migration in animals; flowering, seed germination in plants are regulated by the length of daily period of light and darkness. This behavioural phenomenon is known as photoperiodism. For example, plants such as radish, potatoes and spinach bloom when the light duration is more than 12 hours/day. Such plants are called long day plants. Cereal, tobacco, dahelia and many other plants bloom when light duration is less than 12 hrs/day. These are called short day plants. Such responses show that plants have built-in mechanisms for measuring the duration of illumination and darkness and hence flower in a specific seasons.

Similar photoperiodic responses are observed in animals. These may be diurnal, lunar or annual. Reproduction and migration in birds are such annual photoperiodic responses. From such responses it seems that distribution of some plants and animals may be restricted because the necessary photoperiodic stimulus is available only at certain latitudes.


Related Discussions:- Photoperiodism

Difference between eye and camera, Difference between Eye and Camera - ...

Difference between Eye and Camera -   Camera   Ey e 1. Box.   2. Black inner paint   3. Shutter   4. Diaph

To which direction does the growth of one side of a stem, To which directio...

To which direction does the growth of one side of a stem, branch or root induce the structure to curve? While one side of a stem, branch or root grows more than the other side

Azotobacter, Azotobacter Azotobacter is known to possess the following...

Azotobacter Azotobacter is known to possess the following two mechanisms to protect its nitrogenase from oxygen inhibition. Respiratory protection and Confor

Explain procambium in primary growing shoot, Explain Procambium in primary ...

Explain Procambium in primary growth in shoot ? The vascular tissue in the shoot is produced from a primary tissue called the procambium, located in the apical meristem. New vas

Differnces, difference between protonephridia and metanephridia

difference between protonephridia and metanephridia

Define counter stain - staining technique, Define Counter Stain - Staining ...

Define Counter Stain - Staining Technique? Finally, the smear is counter stained with a simple basic dye different in colour from crystal violet. Safranin is the most commonly

Which is the first heart chamber into which blood enters, Q. Which is the f...

Q. Which is the first (human) heart chamber into which blood enters? Where does the blood go after passing that chamber? What is the name of the valve that separates the compartmen

Radiography, RADIOGRAPHY You  have read  in GNM courses about radiographi...

RADIOGRAPHY You  have read  in GNM courses about radiographical examination. In this text the discussion will be on the following radiographical tests.   Chest Roentgenogram

Discuss the concept of alpha-islet cells of the pancreas, Glycogen A. p...

Glycogen A. production in the liver increases in response to an increase in blood plasma levels of glucagon. B. is secreted by alpha-islet cells of the pancreas. C. bindi

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