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

Principles of numerical taxonomy, Q. Principles of Numerical Taxonomy? ...

Q. Principles of Numerical Taxonomy? Numerical taxonomy is based on the following 7 principles. 1) The greater the content of information in the taxa of a classification is an

What are the main bryophyte groups, Q. What are the main bryophyte groups? ...

Q. What are the main bryophyte groups? The major bryophyte groups are the mosses, the hornworts and the liverworts.

Logistic equation, In order to define growth limit logistic equation was gi...

In order to define growth limit logistic equation was given by Verhulst. In a given ecosystem, the maximum population that can exit is called carrying capacity (k).  The factors wh

Theory of embryology - baer''s law, BAER' S LAW - It was given by K.E....

BAER' S LAW - It was given by K.E. Von Baer. Von Baer was the first scientist who studied the embryology systematically. According to it, in the embryonic development of an

Define methods used in combination with pasteurization, Define methods used...

Define methods used in combination with pasteurization? Typical other methods used in combination with pasteurization include: 1.  Refrigeration as in the case of   milk

Local control mechanism within the circulatory system, Which of the followi...

Which of the following is true for active hyperemia, a local control mechanism within the circulatory system? A. There will be an increase in force developed by smooth muscles

Pharmacological management, Once the decision to start drug treatment of hy...

Once the decision to start drug treatment of hypertension is made, the aim should be to provide 24 hour BP control, with agents that would encourage patient adherence. The patient

Five kingdom classification, discuss the merits nd demerits of five kingdom...

discuss the merits nd demerits of five kingdom classification.

Who were james watson, Q. Who were James Watson, Maurice Wilkins and Franci...

Q. Who were James Watson, Maurice Wilkins and Francis Crick? Watson (North American), Wilkins (New Zealander) and Crick (British) were the discoverers of the molecular structur

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