AQA Biology - synoptic essays - The Student Room.

The nitrogen cycle. The key role of microbes in nitrogen fixation. How overuse of nitrogen-containing fertilizers can cause algal blooms. Google Classroom Facebook Twitter. Email. Biogeochemical cycles. Intro to biogeochemical cycles. Biogeochemical cycles overview. The water cycle. The water cycle. The carbon cycle. The carbon cycle. The nitrogen cycle. This is the currently selected item.

Stage one of the nitrogen cycle Stage one - fixation. About 78 per cent of the air is nitrogen gas. However, nitrogen is too unreactive to be used directly by plants to make protein. It must be.

The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, terrestrial, and marine ecosystems.The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification.

In depth summary's of the cycles included in this essay are: the cell cycle, the phosphorus cycle, the nitrogen cycle, the krebs cycle and the calvin cycle. This essay explores the importance and prevalence of cycles in biology. Revision of this material will be essential as a guide for how to approach the AQA A-Level Paper 3 and will improve your knowledge and ability to link your knowledge.

Nitrogen is essential for all living things because it is a major part of amino acids, which are the building blocks of proteins and of nucleic acids such as DNA, which transfers genetic information to subsequent generations of organisms. About 78 percent of the atmosphere is made of nitrogen, but plants and animals can't take nitrogen directly.

The air we breathe contains 78% nitrogen, 21% oxygen and remaining are other trace gases. The nitrogen component of air is inert. So this means plants and animals cannot use it directly. To be able to use nitrogen, plants convert atmospheric nitrogen to nitrates, nitrites and ammonia compounds by a process called the nitrogen cycle. Animals.

The nitrogen cycle describes how nitrogen moves between plants, animals, bacteria, the atmosphere (the air), and soil in the ground. Nitrogen is an important element to all life on Earth. Different Nitrogen States For Nitrogen to be used by different life forms on Earth, it must change into different states.

Nutrient cycles (A-level only) Hide. 3.5.4 Nutrient cycles (A-level only) Content. Opportunities for skills development. Nutrients are recycled within natural ecosystems, exemplified by the nitrogen cycle and the phosphorus cycle. Microorganisms play a vital role in recycling chemical elements such as phosphorus and nitrogen. The role of saprobionts in decomposition. The role of mycorrhizae in.

The steps of the nitrogen cycle are nitrogen fixation, nitrification, ammonifcation and denitrification. During the first step, nitrogen fixation, special bacteria convert nitrogen gas into ammonia which is used by plants. The second step, nitrification, involves converting ammonia into nitrite ions that are taken by plants as nutrients.

Nitrifying bacterium, plural Nitrifying Bacteria, any of a small group of aerobic bacteria (family Nitrobacteraceae) that use inorganic chemicals as an energy source. They are microorganisms that are important in the nitrogen cycle as converters of soil ammonia to nitrates, compounds usable by plants.

Nitrogen Cycle. Living organisms need nitrogen to make proteins. They cannot get it directly from the air because nitrogen gas is too stable to react inside an organism to make new compounds. Nitrogen must be changed into a more reactive form to allow plants and animals to use it.

Increasing anthropogenic emissions of carbon dioxide from the burning of fossil fuels, alongside the increase in agricultural processes and transport have increased the warming effect of the atmosphere. Levels of carbon dioxide are increased further by deforestation to provide land for agriculture.