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 are the bacteria, Q. What are the bacteria? Bacteria are unicellul...

Q. What are the bacteria? Bacteria are unicellular and prokaryotic beings. Bacteria have simple organization they present an exterior cell wall, plasma membrane, circular DNA w

Temperature - seed dormancy, Temperature - Seed Dormancy Low temperatu...

Temperature - Seed Dormancy Low temperature treatment is an essential prelude to germination in many seeds, and high temperature may be inhibitory at the time of germination.

The reproductive system of house fly, The reproductive system of house fly:...

The reproductive system of house fly: In houseflies seperate male and female organisms are present. Male housefly reproductive system. The male hothe reproductive syste

#white blood cell, #White blood cell has mainly 5 types right? which is Neu...

#White blood cell has mainly 5 types right? which is Neutrophil,Monocytes,lymphocytes, basophil and Eosinophil? I wwanted to know is phagocytes a white blood cell, if yes then why

Types of gonads, Types of Gonads The gonads of vertebrates can be clas...

Types of Gonads The gonads of vertebrates can be classified into the following two types Mammalian type and Non-mammalian type. They differ from

Fluoride - mineral elements, FLUORIDE It is mostly available in drin...

FLUORIDE It is mostly available in drinking water. Fluoride is essential for the formation of enamel of the teeth. Deficiency of fluoride causes weakness of enamel.

Heat exchangers-type of oxygenators , Heat Exchangers :  This is an integr...

Heat Exchangers :  This is an integral part of cardio pulmonary bypass and is designed to cool and warm the perfusate. non-sterile water from ice bath or warm water passed through

How much time is required for a single cell, How much time is required for ...

How much time is required for a single cell of Detoxivicatium completeium to grown into a population large enough to fill the volume of the earth?

Evolution of culture, A general agreerncnt anlong nll the human evolutionis...

A general agreerncnt anlong nll the human evolutionists who may have a very radical philosophical hackground and convictions is that man is the result of an extraordinary evolution

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