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

Lamellar models, LAMELLA R MODELS According to James Danielly & Hu...

LAMELLA R MODELS According to James Danielly & Hugh Davson (1935) cell membrane consists of 4 layers P-L-L-P. Molecules of phospholipid has amphipathic nature, i.e. it

Seed, Seed A seed is a mature ovule enclosing an embryonic plant, stor...

Seed A seed is a mature ovule enclosing an embryonic plant, stored food material (in endosperm, persistent nucellus or embryo itself) and a seed coat formed by one or two inte

Heredity, in humans, maleness of is determined by a pair of sex chromosomes...

in humans, maleness of is determined by a pair of sex chromosomes called X and Y. (a)what is the genotype for males? (b)what is the genotype for females?

Essay, Need an essay for my biology class. Need to know if you can do it. ...

Need an essay for my biology class. Need to know if you can do it. Thank you Instructions. Essay Assignment: Experimental Design Now that you have completed several hands-on la

Zoonoses disease- colibacillosis, Colibacillosis Colibacillosis is caused ...

Colibacillosis Colibacillosis is caused by different strains of Escherichia coli. The disease mainly affects children and travelers. Organisms grow in gut and produce toxin. It ma

Explain thalamus and hypothalamus, Q. Explain Thalamus and Hypothalamus ? ...

Q. Explain Thalamus and Hypothalamus ? Thalamus and Hypothalamus: The thalamus is situated in the forebrain at the uppermost part of the diencephalon (posterior part of the for

Flowering and endogenous rhythms, Flowering and Endogenous Rhythms Th...

Flowering and Endogenous Rhythms The last four decades of studies in animals and plant physiology have clearly established the existence of a biological clock mechanism to me

Define health and feeding problems among elderly, Define Health and Feeding...

Define Health and Feeding Problems among Elderly? Malnutrition, both obesity and under nutrition, are common problems linked with elderly.  Some of the common disorders such as

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