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

What is the phase of the menstrual cycle, In general what is the phase of t...

In general what is the phase of the menstrual cycle when copulation may lead to fecundation? Although this is not a rule, to be effective fecundation in general must happen wit

Biodeterioration, is paper broken down by microorganisms

is paper broken down by microorganisms

Aortic and pulmonary orifices, These circular orifices are located at the u...

These circular orifices are located at the upper ends of the outflow parts of the left and right ventricles respectively. The pulmonary orifice which is 3 cms, is 0.5 cm larger tha

Define functions of calcium in human body, Define Functions of Calcium in H...

Define Functions of Calcium in Human Body? Calcium salts provide rigidity to the skeleton and calcium ions play a role in many if not most, metabolic processes. In the vertebra

What is hypertrichosis of the ear, In humans, attached earlobes are a domin...

In humans, attached earlobes are a dominant feature over free earlobes while hypertrichosis of the ear is a holandric (Y-linked) feature. A person with attached earlobes and extens

Determine the urine analysis, Determine the Urine analysis Urine consti...

Determine the Urine analysis Urine constituent may be altered in urinary tract infection, systemic disease. However it is not routinely prescribed for most of the potential imp

Define percentages of body fat values for athletes, Define Percentages of b...

Define Percentages of body fat values for athletes? Percentages of body fat values for athletes vary depending on the sex of the athlete and the sport itself. Male athletes par

Heat production, Heat Production In the Homeotherms heat production m...

Heat Production In the Homeotherms heat production must be elevated if the ambient temperature falls below the critical temperature. Although all metabolic processes result i

Introduction to locomotion, LOCOMOTIO N - Displacement of body. Mos...

LOCOMOTIO N - Displacement of body. Mostly animals show locomotion except porifera, urochordata, corals, obelia thier larva may show locomotion. Its importance is -

Ability of mammalian kidney, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

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