Name: nitrogen cycle in soil and plants
Uploaded: 2023-04-30T10:06:17.000Z
Duration: 1 min 20 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Life Science

matter-and-energy-in-organisms-and-ecosystems

Matter and Energy in Organisms and Ecosystems

HS-LS1-6.

Overview of Nitrogen Metabolism

L'azoto atmosferico è la principale fonte di azoto. Tuttavia, la maggior parte degli organismi viventi non può assorbire direttamente l'azoto atmosferico a causa del forte triplo legame tra gli atomi di azoto, che lo rende relativamente poco reattivo.
Pertanto, i batteri azotofissatori presenti nel suolo convertono l'azoto atmosferico in ammoniaca, una forma biologicamente utile.
L'ammoniaca può essere assorbita dalle cellule vegetali, dove si combina con il glutammato per produrre glutammina, che viene ulteriormente convertita in altri amminoacidi e nucleotidi.
Successivamente, gli animali consumano queste piante e usano gli amminoacidi per sintetizzare le proprie proteine e nucleotidi.
Poiché gli animali non possono immagazzinare grandi quantità di aminoacidi, gli amminoacidi ingeriti vengono regolarmente scomposti attraverso il ciclo dell'urea in urea.
L'urea viene quindi escreta attraverso l'urina, che alla fine torna nel terreno.
Successivamente, i batteri del suolo con attività ureasica degradano l'urea escreta in ammoniaca. Infine, i batteri nitrificanti e denitrificanti convertono l'ammoniaca in azoto gassoso, restituendolo all'atmosfera.

panoramica del metabolismo dell'azoto

L'azoto è un elemento molto importante per la vita perché è uno dei principali costituenti delle proteine ​​e degli acidi nucleici. È un macronutriente e in natura viene riciclato da composti organici e immagazzinato sotto forma di ammoniaca, ioni ammonio, nitrato, nitrito o gas azoto attraverso molti processi metabolici. Molti di questi processi metabolici vengono eseguiti solo dai procarioti.

La più grande riserva di azoto disponibile nell'ecosistema terrestre è l'azoto gassoso (N_2) presente nell'aria, ma questo azoto non è utilizzabile dalle piante, che sono i principali produttori dell'ecosistema. L'azoto gassoso viene trasformato o "fissato" in forme più facilmente disponibili, come l'ammoniaca (NH_3), attraverso il processo di fissazione dell'azoto. I batteri che fissano l'azoto includono l'Azotobacter nel suolo e gli onnipresenti cianobatteri fotosintetici. Alcuni batteri che fissano l'azoto, come il Rhizobium, vivono in relazioni simbiotiche nelle radici dei legumi. Un'altra fonte di ammoniaca è l'ammonificazione, il processo mediante il quale l'ammoniaca viene rilasciata durante la decomposizione dei composti organici contenenti azoto. Lo ione ammonio viene progressivamente ossidato da diverse specie di batteri in un processo chiamato nitrificazione. Il processo di nitrificazione inizia con la conversione dell'ammonio in nitrito (NO_2^-) e continua con la conversione del nitrito in nitrato. La nitrificazione nei suoli è effettuata da batteri appartenenti ai generi Nitrosomas, Nitrobacter e Nitrospira. La maggior parte dell'azoto nel suolo è sotto forma di ammonio (NH_4^+) o nitrato (NO_3^-). L'ammoniaca e il nitrato possono essere utilizzati dalle piante o convertiti in altre forme.

All'interno delle cellule vegetali, l'ammoniaca si combina con il glutammato per produrre glutammina. La glutammina viene poi ulteriormente convertita in altri amminoacidi e nucleotidi. Successivamente, gli animali consumano queste piante e utilizzano gli amminoacidi per sintetizzare le proprie proteine ​​e nucleotidi. Poiché gli animali non possono immagazzinare una grande quantità di aminoacidi, gli aminoacidi ingeriti vengono regolarmente scomposti all'interno delle cellule. Ma l’ammoniaca libera rilasciata durante il catabolismo degli aminoacidi è altamente tossica per le cellule. Quindi, l’ammoniaca in eccesso viene convertita in una forma non tossica – l’urea – utilizzando una serie di reazioni chiamate ciclo dell’urea. L'urea viene quindi espulsa dal corpo attraverso l'urina e alla fine ritorna nel terreno. Successivamente, i batteri del suolo utilizzano l'enzima ureasi per degradare l'urea escreta in ammoniaca, che può essere nuovamente assorbita dalle piante. Infatti, quando le piante e gli animali muoiono, anche il loro contenuto proteico viene degradato dai microbi per produrre amminoacidi. I microbi nitrificanti presenti nel terreno convertono questi aminoacidi in nitrito e poi in nitrato. Infine, i batteri denitrificanti, alcuni archaea e alcune classi di funghi riconvertono questi nitrati in azoto gassoso, restituendo così l’azoto all’atmosfera.

Questo testo è adattato da <a href="https://openstax.org/books/biology-2e/pages/22-5-beneficial-prokaryotes">Openstax, Biology 2e, Section 22.5: Beneficial Prokaryotes</a>

Panoramica del metabolismo dell'azoto

L'azoto è un elemento molto importante per la vita perché è uno dei principali costituenti delle proteine e degli acidi nucleici. È un macronutriente e, in natura, è ...

Education

Didattica

JoVE Core

Cell Biology

Biologia cellulare

Unit 1

Unità 1

Introduction to Metabolism

Introduzione al metabolismo

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

nitrogen cycle in soil and plants

Nitrogen moves through soil, plants, animals, and microbes in a cycle that keeps this macronutrient available for life. It is a major part of proteins and nucleic acids, so cells need it to build both amino acids and nucleotides.

In nature, nitrogen is recycled from organic compounds and stored in several forms, including ammonia, ammonium ions, nitrate, nitrite, and nitrogen gas. Many of the key steps in this cycle are carried out only by prokaryotes. The largest nitrogen pool in terrestrial ecosystems is gaseous nitrogen from the air, but plants cannot use it directly.

Atmospheric nitrogen must first be fixed into a usable form, such as ammonia, through nitrogen fixation. Nitrogen-fixing bacteria include Azotobacter in soil and photosynthetic cyanobacteria. Some nitrogen-fixing bacteria, such as Rhizobium, live in the roots of legumes in a symbiotic relationship. Ammonia can also form through ammonification, which releases ammonia during the breakdown of nitrogen-containing organic compounds.

After that, ammonium is oxidized step by step in nitrification. The process starts when ammonium becomes nitrite and then continues when nitrite becomes nitrate. In soils, this work is done by bacteria in the genera Nitrosomas, Nitrobacter, and Nitrospira. Most nitrogen in soil is found as ammonium or nitrate, and plants can use these forms or convert them into others.

Inside plant cells, ammonia combines with glutamate to form glutamine. Glutamine is then converted into other amino acids and nucleotides. Animals eat these plants and use the amino acids to make their own proteins and nucleotides. Because animals cannot store a large pool of amino acids, they break them down regularly, and the ammonia released is highly toxic to cells.

To handle this toxicity, animals convert excess ammonia into urea through the urea cycle. Urea is non-toxic and leaves the body in urine. It then returns to the soil, where bacteria with urease break it down into ammonia again. When plants and animals die, microbes also degrade their proteins into amino acids, which are then converted by nitrifying microbes into nitrite and nitrate. Finally, denitrifying bacteria, certain archaea, and some fungi convert nitrate back to gaseous nitrogen, returning it to the atmosphere.

Nitrogen Cycle in Soil and Plants

overview of metabolism

Metabolism in Plants, Animals, and Microbes

Metabolism is the set of chemical reactions that keep living cells working. These reactions are linked through many pathways. Together, they support the normal function of cells in plants, animals, and microbes. In plants, sunlight is the main energy source. Chlorophyll pigments in the leaves absorb this light. The plant then uses that energy for photosynthesis. During photosynthesis, water is oxidized to oxygen and carbon dioxide is reduced to glucose. Glucose then serves as a starting...

carbohydrate metabolism

Carbohydrates, Digestion, and Blood Sugar

Carbohydrates are an important source of energy and a key part of human nutrition. They are made of carbon, hydrogen, and oxygen. One gram of carbohydrate provides four kilo-calories of energy, so carbohydrates are the body’s most efficient instant fuel. Starch makes up about 60% of the carbohydrates people eat. It is broken down by amylase enzymes, but amylase cannot work in the stomach’s acidic environment. That is why starch digestion happens in the mouth and the small intestine. Simple...

glycolysis: preparatory phase

Glycolysis: Energy Investment Steps

Glycolysis begins with energy investment steps in the cytoplasm of both prokaryotic and eukaryotic cells. It is the first step in cellular metabolism, which is the complete breakdown of glucose to extract energy. In heterotrophic cells, glucose enters by secondary active transport or through GLUT proteins, which are glucose transporter proteins that help glucose diffuse into the cell. The pathway starts with one six-carbon, ring-shaped glucose molecule and ends with two three-carbon molecules...

glycolysis: pay-off phase

Glycolysis: ATP and NADH Output

The pay-off phase of glycolysis turns the two three-carbon sugar molecules into ATP, NADH, and pyruvate. By this stage, the cell has already spent two ATP molecules. The remaining reactions recover that investment and add two more ATP molecules and two high-energy NADH molecules. The sixth step oxidizes glyceraldehyde 3-phosphate, a three-carbon sugar made earlier in glycolysis. High-energy electrons are transferred to NAD+, which becomes NADH. A second phosphate group is then added to form...

fates of pyruvate

Pyruvate Pathways in Fermentation

Pyruvate is a key product of glycolysis and can follow different pathways depending on oxygen availability. During glycolysis, glucose is oxidized to pyruvate, NAD+ is reduced to NADH, and two ATP are made by substrate-level phosphorylation. In aerobic organisms, pyruvate then enters the citric acid cycle, which helps produce the reduced coenzymes NADH and FADH2. These coenzymes are later oxidized in the electron transport chain to make ATP and regenerate NAD+ and FAD. When oxygen is absent,...

role of reduced coenzymes nadh and fadh&#8322;

Electron Carriers in Cellular Energy

Electron carriers help store and move energy during nutrient breakdown. Cells can save released energy by reducing these carriers or by making ATP, the cell’s main energy molecule. These mobile electron carriers bind high-energy electrons and shuttle them between compounds in metabolic pathways. The main carriers discussed here come from the B vitamin group and are nucleotide derivatives. They include nicotinamide adenine dinucleotide, nicotinamide adenine dinucleotide phosphate, and flavin...

overview of nitrogen metabolism

Nitrogen moves through soil, plants, animals, and microbes in a cycle that keeps this macronutrient available for life. It is a major part of proteins and nucleic acids, so cells need it to build both amino acids and nucleotides. In nature, nitrogen is recycled from organic compounds and stored in several forms, including ammonia, ammonium ions, nitrate, nitrite, and nitrogen gas. Many of the key steps in this cycle are carried out only by prokaryotes. The largest nitrogen pool in terrestrial...

overview of fatty acid metabolism

Fatty Acids: Energy, Membranes, and Cholesterol

Fatty acids help cells store and use energy, and they also support important cell structures. Lipids are nonpolar and hydrophobic, so they do not mix well with water. Major lipid types include fats and oils, waxes, phospholipids, and steroids. Cells break down fatty acids by beta-oxidation. This process happens in the matrix of the mitochondria and cuts fatty acid chains into two-carbon acetyl groups. CoA picks up these groups to form acetyl CoA, which then enters the citric acid cycle. Extra...

sugars as energy storage molecules

Glucose Storage in Plants and Animals

Glucose storage in plants and animals helps cells manage energy for metabolism. Sugar is a simple carbohydrate, and cells use it because a lot of energy is stored in its bonds. Consumed carbohydrates often come from photosynthesizing organisms, especially plants. Plants make glucose during photosynthesis by using sunlight to convert carbon dioxide into sugar molecules. Because this builds a larger, energy-storing molecule, the process needs an energy input. Glucose can then be stored for later...

fats as energy storage molecules

How Triglycerides Fuel ATP Production

Triglycerides store long-term energy in fats. A triglyceride is built from glycerol and three fatty acids. When the body needs energy, these molecules are broken down first. This breakdown is called lipolysis, and it happens in the cytoplasm by hydrolysis. Lipolysis splits triglycerides into fatty acids and glycerol. The glycerol then enters glycolysis as DHAP, which connects fat breakdown to the cell’s main energy pathway. The fatty acids are then oxidized by beta-oxidation into acetyl-CoA.

regulation of metabolism

How Cells Control Metabolic Enzymes

Cells control metabolic enzymes to match changing needs and conditions. Different cells use different enzymes and energy levels, and those needs can also change within the same cell over time. Stomach cells, fat storage cells, skin cells, blood cells, and nerve cells do not all need the same metabolic activity. A digestive cell also works harder soon after a meal than it does many hours later. As cell needs change, the amount and activity of enzymes change too. Enzymes lower activation energy,...

positive and negative feedback loops

Homeostasis and Body Feedback Control

Homeostasis keeps body conditions in a steady range through feedback control. Animal organs and organ systems constantly adjust to internal and external changes. This balance is called a dynamic equilibrium because the body keeps adapting while still staying within specific ranges. The goal of homeostasis is to stay near a set point, which is the value the body tries to maintain. A change in the internal or external environment is a stimulus. A receptor detects that change and sends a signal...

key terms and concepts

Trace how nitrogen is fixed, turned into ammonium and nitrate, used by plants and animals, and returned to the air by microbes in the soil.

Nitrogen Cycle in Soil and Plants | JoVE K12

cell biology

JoVE Core Cell Biology illustrates complex cellular processes in easy-to-understand yet comprehensive animated video lessons. This collection focuses on the essential components and functions of cells, including organelles and membranes, cellular transport, and cell energetics. It is complemented by scientist-in-action videos that demonstrate the application of cell biology in real-world research experiments.

Georgia Standards of Excellence

9-12

Botany

SBO1.

coevolution-plant-morphological-anatomical-structures-with-animals-ie

Coevolution of plant morphological and anatomical structures with animals (i.e., pollination), Rhizobium (i.e., nitrogen fixation), and Mycorrhiza (i.e., fungi in rhizosphere).

What is Photosynthesis?

Photosynthesis is a multipart, biochemical process that occurs in plants as well as in some bacteria. It captures carbon dioxide and solar energy to ...

Light as Energy

The energy required to carry out photosynthesis is light&#8212; typically electromagnetic radiation from the sun. The range of all possible wavelengths is ...

Anatomy of Chloroplasts

Green algae and plants, including green stems and unripe fruit, harbor chloroplasts&mdash;the vital organelles where photosynthesis takes place. In ...

Photosystem II

The multi-protein complex photosystem II (PS II) harvests photons and transfers their energy through its bound pigments to its reaction center, and ...

Photosystem I

Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these ...

The Calvin Cycle

Overview

Oxygenic photosynthesis converts approximately 200 billion tons of carbon dioxide (CO2) annually to organic compounds and produces approximately ...

C4 Pathway and CAM

Most plants use the C3 pathway for carbon fixation. However, some plants, such as sugar cane, corn, and cacti that grow in hot conditions, use alternative ...

the-z-scheme-of-electron-transport-in-photosynthesis

The Z-Scheme of Electron Transport in Photosynthesis

The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of ...

Photosynthesis

Autotrophs

Almost all living organisms on Earth depend on photosynthesis, which is the process that converts sunlight energy into a simple sugar called ...

Plant Pigment Chromatography and Floating Leaf Discs in a Vacuum
ExpandOn the day before the experiment, fill a container with water.
Place the spinach ...

Plant Pigment Chromatography
ExpandNOTE: In this experiment you will separate pigments from spinach leaves using chromatography paper. Individual pigments ...

First Law of Thermodynamics

The First Law of Thermodynamics states that energy cannot be created or destroyed, only transformed. This can be demonstrated within a classic food web ...

Photosystems

Photosystems are multiprotein complexes that form the functional units of photosynthesis in plants, algae, and cyanobacteria. They are found embedded in ...

An Introduction to Cell Metabolism

In cells, critical molecules are either built by joining together individual units like amino acids or nucleotides, or broken down into smaller ...

Reconstitution of Membrane Proteins

Reconstitution is the process of returning an isolated biomolecule to its original form or function. This is particularly useful for studying membrane ...

Use a model to illustrate how photosynthesis transforms light energy into stored chemical energy.

HS-LS1-5.

Macromolecules

Biomolecules
Organisms contain a wide variety of organic molecules with numerous functions which depend on the chemical structures and properties of these ...

Solution Preparation
ExpandCAUTION: It is important to always use care when handling reagents. For example, iodine will stain clothes and skin so wear ...

Identifying Macromolecules with Indicator Solutions
ExpandHYPOTHESES: In this activity, the experimental hypothesis might be that the addition of an ...

Introduction to Carbohydrates

Carbohydrates, proteins, and fats are the primary macronutrients in the human diet. However, carbohydrates are the most favored source of energy in the ...

Carbohydrate Metabolism

Sugars as Energy Storage Molecules

Chemistry of Carbohydrates

Carbohydrates are an essential part of the diet in humans and animals. Grains, fruits, and vegetables are natural sources of carbohydrates that provide ...

Oligosaccharide Assembly

Protein glycosylation starts in the ER lumen and continues in the Golgi apparatus. Glycosyltransferases catalyze the addition of sugar molecules or ...

What are Lipids?

lipid-derived-compounds-in-the-human-body

Lipid-derived Compounds in the Human Body

Fats and lipids are crucial components in the human body. Some lipid-derived compounds, such as fat-soluble vitamins, eicosanoids, lipoproteins, and ...

Fats as Energy Storage Molecules

Structure of Lipids

Lipids include a diverse group of compounds that are largely nonpolar in nature. This is because they are hydrocarbons that include mostly nonpolar ...

Proteins and Amino Acids

Overview

Proteins are chains of amino acids that are connected by peptide bonds and folded into a 3-dimensional structure. The side chains of individual ...

Amino acids

Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the ...

Peptide Bonds

A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid&#x27;s carboxyl group and another amino acid&#x27;s amino ...

Nucleic Acids and Nucleotides

Nucleic acids are the most important macromolecules for the continuity of life. They carry the cell&#39;s genetic blueprint and have instructions for its ...

Nucleic Acid Structure

The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group ...

Conditions on Early Earth

Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen ...

ATP and Macromolecule Synthesis

Biological macromolecules are organic compounds, predominantly composed of carbon atoms. The carbon atoms are covalently bonded with hydrogen, oxygen, ...

Dietary Connections

In biological systems, most metabolic pathways are interconnected. The cellular respiration processes that convert glucose to ATP&#8212;such as ...

From DNA to Protein

The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of ...

Nitrogen is a very important element for life because it is a major constituent of proteins and nucleic acids. It is a macronutrient, and in nature, it is ...

Compounds Essential to Human Function

The human body is composed of cells that are fundamentally made up of several different molecules. These molecules are essential to carry out all ...

an-introduction-to-molecular-developmental-biology

An Introduction to Molecular Developmental Biology

Molecular signals play a major role in the complex processes occurring during embryonic development. These signals regulate activities such as cell ...

Dehydration Synthesis

Dehydration synthesis (also called a condensation reaction) is the chemical process in which two molecules covalently link together to form a new ...

an-introduction-to-saccharomyces-cerevisiae

An Introduction to Saccharomyces cerevisiae

Saccharomyces cerevisiae (commonly known as baker&rsquo;s yeast) is a single-celled eukaryote that is frequently used in scientific research.  S. ...

An Introduction to Transfection

Transfection is the process of inserting genetic material, such as DNA and double stranded RNA, into mammalian cells. The insertion of DNA into a cell ...

All living organisms on Earth are directly or indirectly dependent on photosynthesis. It is the only biological process that can capture energy from ...

an-overview-of-alkenone-biomarker-analysis-for-paleothermometry

An Overview of Alkenone Biomarker Analysis for Paleothermometry

Source: Laboratory of Jeff Salacup&#160;- University of Massachusetts Amherst
Throughout this series of videos, natural samples were extracted and ...

an-introduction-to-caenorhabditis-elegans

An Introduction to Caenorhabditis elegans

Caenorhabditis elegans is a microscopic, soil-dwelling roundworm that has been powerfully used as a model organism since the early 1970&rsquo;s.  It was ...

An Overview of Epigenetics

Since the early days of genetics research, scientists have noted certain heritable phenotypic differences that are not due to differences in the ...

An Introduction to Cell Death

Necrosis, apoptosis, and autophagic cell death are all manners in which cells can die, and these mechanisms can be induced by different stimuli, such as ...

An Overview of Gene Expression

Gene expression is the complex process where a cell uses its genetic information to make functional products. This process is regulated at multiple ...

An Introduction to Cell Division

Cell division is the process by which a parent cell divides and gives rise to two or more daughter cells. It is a means of reproduction for single-cell ...

An Overview of Genetic Analysis

An organism&#8217;s physical traits, or phenotype, are a product of its genotype, which is the combination of alleles (gene variants) inherited from its ...

an-introduction-to-cell-motility-and-migration

An Introduction to Cell Motility and Migration

Cell motility and migration play important roles in both normal biology and in disease. On one hand, migration allows cells to generate complex tissues ...

An Overview of Genetic Engineering

Genetic engineering &#8211; the process of purposefully altering an organism&#8217;s DNA &#8211; has been used to create powerful research tools and model ...

an-introduction-to-cellular-and-molecular-neuroscience

An Introduction to Cellular and Molecular Neuroscience

Cellular and molecular neuroscience is one of the newest and fastest growing subdisciplines in neuroscience. By investigating the influences of genes, ...

An Overview of Genetics and Disease

Many human diseases are associated with mutations or variations in genetic sequences. Some of these genetic variants are heritable, passed down from ...

an-introduction-to-developmental-genetics

An Introduction to Developmental Genetics

Development is the complex process through which a single-celled embryo transforms into a multicellular organism. Developmental processes are guided by ...

an-overview-of-bgdgt-biomarker-analysis-for-paleoclimatology

An Overview of bGDGT Biomarker Analysis for Paleoclimatology

Annexin V and Propidium Iodide Labeling

Staining with annexin V and propidium iodide (PI) provides researchers with a way to identify different types of cell death&#8212;either necrosis or ...

co-immunoprecipitation-and-pull-down-assays

Co-Immunoprecipitation and Pull-Down Assays

Co-immunoprecipitation (CoIP) and pull-down assays are closely related methods to identify stable protein-protein interactions. These methods are related ...

Bacterial Transformation: Electroporation

The term &#x201C;transformation&#x201D; refers cellular ingestion of foreign DNA.  In nature, transformation can occur in certain types of bacteria.  In ...

Column Chromatography

Source: Laboratory of Dr. Jimmy Franco - Merrimack College
Column chromatography is one of the most useful techniques for purifying compounds. This ...

bacterial-transformation-the-heat-shock-method

Bacterial Transformation: The Heat Shock Method

Transformation is the process that occurs when a cell ingests foreign DNA from its surroundings. Transformation can occur in nature in certain types of ...

community-dna-extraction-from-bacterial-colonies

Community DNA Extraction from Bacterial Colonies

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - The University of Arizona
Demonstrating Author: Luisa Ikner
Traditional methods of analysis ...

Construct and revise an explanation based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements such as nitrogen, sulfur, and phosphorus to form amino acids and other carbon-based molecules.

Nitrogen Cycle in Soil and Plants

Description

Transcript

Tags

More videos by Standards