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

Determine the membrane voltage of neuron b, Consider Neuron B in the frog c...

Consider Neuron B in the frog central nervous system whose plasma membrane has a previously unknown channel that is selectively conductive to a newly discovered tetravalent anion n

Gonads, GONADS - They develop from the mesoderm of the embryo. The g...

GONADS - They develop from the mesoderm of the embryo. The gonads are the sex glands; the ovaries and the testes. They produce ova and sperms respectively i.e. cytogenic in

Munch pressure flow model, Munch Pressure Flow Model Munch, a German p...

Munch Pressure Flow Model Munch, a German plant physiologist, proposed in 1930, a simple physical model which can be tested in the laboratory for the mechanism of phloem trans

What is meant by the arch reflex, Q. What is meant by the arch reflex? ...

Q. What is meant by the arch reflex? In some situations the movement of the skeletal striated muscles does not depend upon commands of the superior motor neurons that it is not

Define meiosis, Give two examples in each case of organs or tissues in whic...

Give two examples in each case of organs or tissues in which you would expect  (a) meiosis,  (b) mitosis to be taking place   a) Meiosis is likely to

What is the phenomenon of apical dominance in plants, What is the phenomeno...

What is the phenomenon of apical dominance in plants? How can it be artificially eliminated? Apical dominance is the phenomenon by which high (over the positive range limit) au

Explain about the cheese making - methods of food processing, Explain about...

Explain about the Cheese Making - methods of food processing? Cheese is a way of preserving milk for long periods of time. In this process, the milk in cheese becomes something

Vertebrates, i need examples of animals that belongs to vertevrate pisces

i need examples of animals that belongs to vertevrate pisces

What do you mean by synapses, Q. What do you mean by synapses? Synapses...

Q. What do you mean by synapses? Synapses are the structures that transmit the neural impulse between two neurons. When the electric impulse arrives the presynaptic membrane

Bacteria and archea, Based on the scientific name. Streptococcus agalactia...

Based on the scientific name. Streptococcus agalactiae what morphology would you expect these cells to have?

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