Senescence, Biology

Assignment Help:

Senescence

Plants begin their development after seed germination. They grow, flower and finally senesce and die. The period from the start to death is called the longevity or age or life span and this period varies from species to species. For example, some plants, like annuals, complete their life cycles within a few months whereas others live for a few centuries. For example, the life of Juniperus scopulorum is around 3,000 years. The period just before death is called the senescent period.

This may be compared to old age in animals. In this period deterioration occurs because there is a consistent decrease in viability and increase in vulnerability. This phase can be prolonged but cannot be reversed. Senescence may occur very quickly or may be a very slow process. In a plant sometimes the individual organs senesce while the whole plant may remain healthy. In annuals, the whole plant dies; in biennials, the plant dies only after two years, whereas in perennials, year after year the leaves and fruits are shed but the main plant survives.


Related Discussions:- Senescence

Explain chymotrypsin, Chymotrypsin Chymotrypsin  is secreted in an ina...

Chymotrypsin Chymotrypsin  is secreted in an inactive form  'chymotrypsinogen',  which  is activated by  trypsin. Chymotrypsin  is specific  for  peptide  bonds containing unc

Explain about the pickling - methods of food processing, Explain about the ...

Explain about the Pickling - methods of food processing? Pickling was widely used to preserve meats, fruits and vegetables in the past, but today it is used almost exclusively

Carbon filtration or activated carbon process, Activated carbon has a much ...

Activated carbon has a much higher adsorption capacity than other materials. Carbon adsorbs objectionable odours, flavours, organic compounds and many hazardous chemicals. There

Plantae, significance of amoebozoa

significance of amoebozoa

Describe the terms diffusion osmosis and filtration, Describe the terms dif...

Describe the terms diffusion, osmosis and filtration. Explain why each process is important for the human body.

Explain about human auditory sensitivity, What are the structures that part...

What are the structures that participate in the human auditory sensitivity? The structures of the human auditory sensitivity are the ears (external, middle and internal), the

What are catalysts, Catalysts are substances that decrease the activation e...

Catalysts are substances that decrease the activation energy of a chemical reaction, facilitating it or making it energetically viable. The catalyst enhances the speed of the chemi

Epidemiology, Epidemiology:   The study of disease in populations.  In...

Epidemiology:   The study of disease in populations.  Includes: The Aetiology of the disease Patterns of distribution of the disease How the disease spread

Dietary management of oesophagitis, Q. Dietary Management fo oesophagitis? ...

Q. Dietary Management fo oesophagitis? Providing adequate nutrition support may require emphasis of different aspects during acute and chronic oesophagitis. In acute phase,

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