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!
Symbiotic Nitrogen Fixers - Nutrient Cycles
Of the symbiotic nitrogen fixing bacteria, species of Rhizobium form root nodules in legumes and are the most studied nitrogen fixers and the best understood. Species of Rhizobium are most specific to particular species of legumes. The rhizobia penetrate the root hair and once inside the root, the bacteria rapidly multiply and form swollen, irregular - shaped bodies in roots of legumes. Some non-legume w6ody plants also have root nodules and fix nitrogen symbiotically.
The organisms that cause the formation of nodule and fixation of nitrogen are actinomycetes (a kind of primitive fungus). Some examples of non-legumes are species of Alnus, Elaeagnus Myrica, Araucaria, Ginkgo, and Casuarina. Unlike legumes, which are largely tropical in origin, these nitrogen fixers originate in the temperate zone. Nitrogen fixation by blue green algae or cyanobacteria may take place in free living forms or in symbiosis with fungi as in certain lichens, mosses ferns and at least one seed plant. The fronds of the small free floating aquatic fern Azolla contain small pores filled with symbiotic blue green algae Anabaena that actively fix nitrogen. For centuries this fern has played an important role in the rice fields of China. Before the rice fields are planted the water filled paddy fields are covered with the aquatic fern which fixes enough nitrogen for the crop as it matures. This practice permits rice to be grown without further addition of nitrogen fertilisers. Symbiotic nitrogen fixers are more efficient than free living ones.
What are the noteworthy features of the nervous system of arthropods? In arthropods the nervous system has more complicated sensory receptors with well-advanced cephalization.
Q. Defense mechanisms used in Diabetes Mellitus? Defense mechanisms are the strategies to cope with the real situation and to maintain self-image. Healthy persons normally use
Q. What is tuberculosis? How is the disease transmitted? Is there treatment for tuberculosis? The Tuberculosis is a disease caused by the Mycobacterium tuberculosis bacteria wh
Explain the Objectives of Taxonomy Let us summarise the objectives of taxonomy: 1. To inventory the world flora and fauna 2. To provide a method for identification and co
Q. List the stages of process of behaviour change? Stages of behaviour change process: · Unawareness · Awareness · Acquiring knowledge · Motivation · Trial
What is lamarckism? The Lamarckism is the theory that unites the law of use and disuse with the law of the transmission of acquired characteristics that is that asserted that a
what is biological sickness of soil and its management
Optic vesicle We have explained earlier that the presumptive material for the optic vesicles lies in qe eye field in the anterior region of the early neural plate. Experiments
What is Ground Meristem in primary growing shoot? The ground meristem produces new cells which ultimately develop into parenchyma cells. The central portion of the primary shoo
Define Economic Evaluation of Malnutrition? You must be familiar with a proverb frequently used in the field of economics, which says - "resources are limited and wants are unl
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