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Effect of co2 on photosynthesis
Effect of co2 on photosynthesis
The effect of co2 concentration on photosynthesis
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The leguminosae family, more commonly known as the legume, pea, or bean family; contain most of the plant species that form a symbiotic relationship with nitrogen fixing bacteria. About 20,000 species of legumes form their symbiosis with rhizobia; a nodule-inducing bacteria. Legumes have emerged as a very valuable resource for many countries for various reasons. The seeds of legumes are very high in protein, and some can also be rich in oil. Some countries donate up to 60% of their arable land in order to plant various types of this plant family. This family of plants is also used to enhance soil fertility and is a valuable source of wood. In various agricultural systems, the need for chemical fertilizer is greatly reduced due to the nitrogen fixation of the symbiotic bacteria that is hosted by the legumes. In some areas, almost 50% of the nitrogen added to the soil is due to this symbiotic relationship (3). Although an exact estimate of this symbiosis is hard to determine, legume-rhizobia relationships remain important to the function and composition of many natural ecosystems throughout the world (2). The basis for the symbiotic relationship in these species is complex. The infection of the host cell by rhizobia occurs within the plant’s root nodules. Bacteroides, gram-negative anaerobic bacteria, are isolated from the host cell by a peribacteroid membrane; the membrane between the plasma membrane of the cell and the membrane of the bacteroid. The bacteroid contains differentiated rhizobia, which are able to fix nitrogen due to the supply of carbon from the host plant. Sucrose is delivered to the nodules of the root via the phloem, where it is cleaved by suc synthase, and enters the Krebs cycle. The product of glyco... ... middle of paper ... ...ion amplifies the benefits of nitrogen fixation in legumes (2). These studies have helped to further the understanding of how legumes respond in elevated carbon dioxide. Researchers have determined that growth at elevated carbon dioxide concentrations stimulates photosynthesis and the increase of carbon to the plant. However this increase requires a higher nutrient supply to account for the increase in photosynthetic output. Based on these findings, legumes have a competitive advantage over nonleguminous plants when grown at elevated level of carbon dioxide. In natural settings however, nutrient availability greatly affects the response of these legumes (2). Legumes are dependent on their symbiotic relationship to nitrogen fixing bacteria, and this relationship and its response to elevated concentrations of carbon dioxide will continue to be studied for years.
One of the main questions addressed is; why do plants choose rhizobia with nitrogen fixing strains (as nitrogen is metabolically costly) over plants with non-fixing strains that can also lead to nodulated plant (Gubry-Rangin et al, 2010). It should be noted that strains with different fixing levels have been reported in populations of rhizobia and when picking a rhizobium a plant must take into consideration its symbiotic efficacy, as rhizobia cannot be vertically transmitted.
As a result of these factors, the flora has adapted to these conditions in a variety of ways including their shape, leaf type, root system, and color. One of the most prominent adapt...
(ii) Motility and chemotaxis. In addition to their role in the attachment of microorganisms to plant roots, functional flagella are important for bacterial motility. The crucial role of motility for successful rhizosphere colonization is somewhat controversial because some studies have indicated that motility of Pseudomonas is not required for root colonization in wheat and soybean (Howie et al. 1987). However, flagella were shown to be essential for colonization of potato roots (de Weger et al. 1987). Studies confirming the role of motility in the colonization process were performed in the absence of percolating water, and it was assumed that motile or non-motile introduced bacterial strains were transported by the growing roots. However, under more natural conditions the presence of percolating water will affect the dispersal of bacterial strains regardless of their ability to swim.
Schumann, Gail L., and Cleora J. D'Arcy. Hungry Planet: Stories of Plant Diseases. St. Paul: American Phytopathological Society, 2012. Print.
2. (2 pts) Contrast the potential contributions of Azotobacter versus Rhizobia/Bradyzhizobia to the nitrogen budget in soils. Discuss why they are so different.
Syphilis is a sexually transmitted disease (STD) caused by Treponema pallidum pallidum. Syphilis can also be passed from mother to infant during pregnancy. Syphilis can cause massive damage to body if left untreated. Known as “the great imitator” because several of the symptoms of syphilis are similar to other diseases, making it hard to pinpoint Syphilis’ origin (what is syphilis). Scientists and other professionals have come up with multiple hypotheses for the suggested origin of syphilis. There are three hypotheses currently being discussed. The first hypothesis states that syphilis was always in the Old World and syphilis probably evolved during the early Paleolithic in Africa or the Near East. According to this hypothesis, syphilis was transported to the New World by Columbus. This hypothesis is known as the “Pre-Columbus” hypothesis. The second hypothesis states syphilis was only in the New World. Syphilis was brought back to the Old World by Columbus and his crew. Columbus and crew returned to Europe, and shortly after, there was an epidemic of syphilis. This hypothesis is known as the “Columbus” hypothesis. The third hypothesis states that syphilis was present in both the Old World and the New World. This hypothesis is known as the “Unitarian” hypothesis. Evidence for these hypotheses have been collected and will be used to decide which hypothesis is more likely true or if more than one hypothesis is needed to explain the origin of syphilis. It is very likely that syphilis, when it was not viral, travelled from the Old World to the New World with Natives of the Americas during the mass migration around 16-14 thousand years ago and later on, the syphilis bacteria became viral. Also, syphilis could have been present in the O...
In this lab, cellular respiration in germinating and dry peas at two different temperatures were explored. During cellular respiration, sugar and oxygen are taken in and broken down to create ATP, heat energy, and water. Aerobic respiration consists of three main stages: Glycolysis, Acetyl CoA formation, the Krebs cycle, and
The knots on the roots of leguminous plants (i.e., clover, beans, peas, alfalfa) contain bacteria belonging to the genus Rhizobium. While growing together with the plants, this genus Rhizobium gathers nitrogen from the air and combines it into substances essential for the growth of both the bacteria and the plants. The process is known as symbiotic nitrogen fixation
This finding led to conclude that the DMI3 gene may play an important role in the plant's response to calcium oscillations. It is necessary for Rhizobial and Mycorrhizal interactions and encodes a calcium and calmodulin-dependent kinase. In the process of working on nitrogen fixation, we have discovered a general method for identifying important plant genes that is fast and may be applicable to almost any plant species.
amount of carbon-dioxide (CO ) and the temperature that can be used by the plant. I
Whiting D., O’Meara C., Wilson C. 2013. Vegetable Garden: Soil Management and Fertilization. [Citing 2014 February 20]; Available from http://www.ext.colostate.edu/mg/gardennotes/711.html.
Organisms need their own set of nutrients. These nutrients are what help the cell survive so that the whole organism could survive. Organisms have their own set of nutrients. On earth there are three domains of life. These domains are the bacteria, Archaea, and eukarya (Brooker et al. 2013) most of the cells that are being researched and examined are cells in the domain Eukarya because cells in this domain usually exists in a multicellular complex. In the domain eukarya, the genus that was examined in this lab was Ceratopteris, which is also called c-fern; this plant is used in research to see how plant growth is affected by various changes that affect plant growth. (Lloyd, 1973) The reason that c-fern is used to do research is because of it’s developmental process. The reason why their life cycle is so unique is because it has a biphasic life cycle that has two independent diploid and haploid generations. (Hickok et al., 1995) This is useful because the haploid and the diploid can be isolated which will provide information on how each variable effect each different stage during each life cycle. (Hickok et al., 1995) another advantage of why c-ferns are used in research is because of their short life cycle. After inoculation, germination occurs in the following 3-4 days and full sexual maturity occurs between 6-8 days after germination. After one to two weeks, roots and leaves start to appear on the diploid sporophyte. (Hickok et al., 1995) these are the main reasons why c-ferns were chosen to see the effects of nitrogen on.
Nitrogen, Phosphorus and Potassium are the three most important nutrients required for a plant’s survival. Nitrogen, an element found in all cells, is a major part of all amino acids (Bozeman, 2004) and is essential for plant growth and fruit production (CS, Unknown). In a process called Nitrogen fixation, dinitrogen (N2) is converted into ammonia (NH3) by nodules formed by a symbiotic relationship between legumes and soil bacteria called Rhizobia. The ammonia is transported into plant tissues where it is transformed into amino acids that are used in various plant processes (Boundless.com, Unknown).
Although parasitology had its origins in the zoologic sciences, the more précising term "Medical parasitology" would refer to the study of a group of pathogens classified as eukaryotes, under the Knigdom of animalia, that cause a wide range of diseases in the human beings. Human parasites can be generally divided into three broad categories; parasitic protozoa, parasitic helminths (worms), and arthropods that either cause a disease directly or act as vectors or vehicles for transmission of various pathogens biologically and mechanically 1.
Nitrogen is essential for plants because it is an essential component of all proteins. A lack of nitrogen in a plant diet can result in slower growth, stunted growth, and even chlorosis (1). Plants affected by chlorosis produce insufficient amounts of chlorophyll, reducing its ability to make carbohydrates through photosynthesis. These plants become a yellowish or pale color and eventually die from the lack of chlorophyll. (2) All of the transformations that nitrogen goes under in and out of the soil are known as the nitrogen cycle. Plants lose nitrogen from their soil system through run-off, leaching, volatilization, and denitrification. Most of the nitrogen that plants uptake from the soil is in the forms of ammonium and nitrate. Proteins and amino acids can only be built from nitrate and ammonia and therefore must be reduced. Organic nitrogen, found in organic matter, is converted into ammonium in the process...