Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Types of xerophytes
On the basis of their mbrphology, physiology and life cycle pattern, xerophytes are generally classified into the following three categories:
a) Ephemeral annuals also called drought evaders or drought escapers are common in arid zones. These annuals are able to complete their life cycle within a short period of 6-8 weeks during which moisture conditions are favourable. As the moisture gets depleted these annuals dry out leaving behind a crop of seeds to tide over the adverse dry period. They actually avoid the dry period and form seeds which are highly resistant to aridity. Argemone mexicana, Solanurn xanthouupum and Cassia tom are good examples of drought escapers.
b) Succulents: Plants adapted to hot and dry areas are called succulents. They have fleshy stem, leaves and roots which are swollen and serve as water storage organs. These plants are able to accumulate large amounts of water during the brief rainy season. To minimise water loss from the plants leaves either become very small or modify into thorns or are absent altogether to cut down water loss through transpiration. The root system is shallow, with wide horizontally spread stem and leaves are thick, swollen and leathery. Examples of succulents are Opuntia sp., Euphorbia splendens and various types of cacti, and Agave. In many cases stems become succulent as in Opuntia and Eupborbia splendens. They are also called fleshy xerophytes. In such xerophytes, cuticle is thick with a well developed two to three layered hypodermis.
c) Non-succulent perennials: These are actually the true xerophytes or drought resistants, because they possess a number of morphological, anatomical and physiological characteristics which enable them to withstand critical dry conditions. They exhibit rapid root growth and form an extensive root system to tap water from the soil in a most efficient manner. The leaf size is greatly reduced and in many xerophytic grasses, leaves roll on to reduce the leaf surface for restricting loss of water due to transpiration. Some of the examples are Calotropis procera, Acacia nelotica, Saccharurn munja In non-succulent xerophytes, root system is very extensive e.g. Calotropis.
Bacterial vaginosis The role of sexual transmission is unclear in bacterial vaginosis, in which normal H2O2-producing Lactobacillus species are replaced by overgrowth with G
Q. What is the glycolysis? And what are the products of this process? Glycolysis, the first stage of the aerobic cell respiration is a process in which glucose is degraded brok
Explain the Observation or Inference for seliwanoff's test? 1. Wine or cherry red colour seen. Wine red colour confirms the presence of a ketose sugar. Note: On overheating
Define Protective role and Metal chelating ability? Protective role: Nicotinic acid is vital to the normal functioning of the skin intestinal tract and nervous system. It p
Hydrarch - Ecology Its various stages are well studied in ecosystem like ponds, pools and lakes. Since pond is a fresh water ecosystem, the succession in it is also referred t
What is the main difference between a bird heart and a mammalian heart? The bird heart has a one aortic arch on the right side of its body while the mammalian heart has one on
What the difference is between type I diabetes mellitus and type II diabetes mellitus? Type I diabetes, also called as juvenile diabetes, or insulin-dependent diabetes (this na
Do plants placed under an environment drier than the habitat where they are used to living have a reduction or an increase in the time during which their stomata remain open? I
Setting priorities for action: It is not enough for our actions to be coordinated with events in the outside world; they must reflect our internal needs. Pain can flood conscious
Q. Effects of smoking on oesophagitis? 1. A decrease in pyloric sphincter pressure which may predispose an individual to duodenal ulcer. 2. An alteration in the nature of ga
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd