Energy storage in the cell: Difference between revisions

Latest revision as of 17:58, 15 January 2024

All biochemical events taking place in the cell are dynamic, i.e. the events by which energy is obtained and consumed. As a living organism, the cell has the ability to manage its own energy, store it or use it again from the stored reserves.

Metabolism[edit | edit source]

Metabolism is a concept that includes all the enzymatic reactions controlled by a living organism. Metabolism can be further divided into catabolic reactions, defined as reactions that involve breaking down larger molecules into smaller structures, and anabolic reactions, whose task is to build more complex substances from smaller blocks for a certain purpose. Catabolic reactions result in energy gain while anabolic reactions consume energy.

In terms of energy gain, organisms are divided into two large groups:

Phototrophic organisms: obtain chemical energy from light (mostly includes plants).
Organotrophic organisms: obtain energy from chemical reactions (eg animals).

There is a symbiotic relationship between these two groups of organisms, which could be referred to as the basic concept of metabolism and bioenergetics.

Phototrophic organisms use light energy to construct sugars and oxygen from molecules of water and carbon dioxide. This in turn serves heterotrophic organisms, which oxidize sugars with the help of oxygen through the process of internal respiration, leading to the production of energy. Every living object constantly requires a supply of energy from its surroundings for vital processes. From a bioenergetics perspective, the essence of these processes is the transformation of one type of energy into another. There is a state of balance between the supply and demand of energy.

The balance between anabolic and catabolic processes can vary in both directions over time, and the following cases can occur:

The organism consumes energy or there is a demand for an energy source in the organism. Energy is produced as catabolic processes prevail over anabolic ones
The organism's energy intake is greater than its output - energy accumulates and the supply is greater than the demand. The organism has to somehow deal with such an amount of excess, in other words - it has to store it (meaning anabolic processes will prevail over catabolic one).

The essence of energy storage in the cell[edit | edit source]

This concept can be illustrated nicely using the example of food processed by the organism after intake.

The sugars, or glucose, is brought to the liver. About half of the substance is converted into glycogen while the rest passes through the liver into the blood. Glucose enters erythrocytes and the CNS. This is done without the need for insulin and glucose is then further metabolized there to produce energy. The remaining glucose also enters skeletal muscle cells, although it requires the aid of insulin in this case. Here it is either consumed or stored in the form of glycogen as an energy reserve. After the liver's capacity for glycogen synthesis is exceeded, glucose is converted into triacylglycerols and stored as an energy reserve in adipose tissue.

Amino acids (created by the breakdown of proteins) are also transported by the blood to the liver and other tissues. In the liver and other tissues, they serve as basic building blocks for protein synthesis, with others being transported into the blood by binding to specific carriers. There is no organ in the organism that serves as a reservoir of amino acids or nitrogen. Therefore, the excess of amino acids is mainly broken down into glucose, and the nitrogenous residue is excreted as urea.

Lipids enter the blood as chylomicrons via the lymphatic system. When associated with specific proteins, lipids are transported by the blood and absorbed by tissues for metabolic needs or transported to fat tissue, where they are stored.

Postprandial nutrient metabolism[edit | edit source]

If a person is lying down and at rest after a meal, the largest part of the nutrients transferred into the body will be converted into stored fats during digenstion. In particular, it occurs after exceeding the capacity for glycogen synthesis (in the liver and muscles). Additional excess glucose (whether received in the pure form of glucose or substances converted into glucose secondarily) is stored in the form of triacylglycerols in adipose tissue. This happens because the concentration of ATP prevails over ADP in the cells (if no work is done, no ATP is consumed) and both the process of glycolysis and the process of aerobic phosphorylation are greatly slowed down in this state.
However, if motor activity begins to develop after a meal, then the way nutrients are transformed changes significantly. Nutrients will primarily be used as a source of energy. These reserves of primarily usable nutrients are used up and only then can the energy reserves, which the cell has stored in a reserve of mainly fats – i.e. reserve triacylglycerols from adipose tissue, be depleted.

Links[edit | edit source]

References[edit | edit source]

Biochemistry in pictures and diagrams; Prof. MD RNDr. Jan Musil, DrSc., Avicenum 1990
Harper's Biochemistry; Murray K. Robert, Daryl K. Granner; Publishing house HaH, 2002

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-{{Under construction}}
+All biochemical events taking place in the cell are dynamic, i.e. the events by which energy is obtained and consumed. As a living organism, the cell has the ability to manage its own energy, store it or use it again from the stored reserves.
-Veškeré biochemické děje probíhající v buňce jsou dynamické tzn. energie se získává a spotřebovává. Buňka, coby živý organismus, má možnost s energií hospodařit, ukládat si jí nebo ji z uložených zásob opět použít.
+==Metabolism==
-==Metabolismus==
+Metabolism is a concept that includes all the enzymatic reactions controlled by a living organism. Metabolism can be further divided into catabolic reactions, defined as reactions that involve breaking down larger molecules into smaller structures, and anabolic reactions, whose task is to build more complex substances from smaller blocks for a certain purpose. Catabolic reactions result in energy gain while anabolic reactions consume energy.<br />
-'''Metabolismus''' je pojem zahrnující soubor všech enzymatických reakcí řízených v živém organismu.
-Metabolismus můžeme dále rozdělit na [[katabolické reakce|reakce katabolické]], jejichž podstatou je rozklad větších molekul a zisk energie a [[anabolické reakce|anabolické]], jejichž úkolem je stavět z menších bloků látky složitější za jistým úkolem. Anabolické reakce naopak energii spotřebovávají. <br />
-Z hlediska zisku energie se organismy dělí na dvě velké skupiny:
+In terms of energy gain, organisms are divided into two large groups:
-*fototrofní organismy: získávají chemickou energii ze světla (např. rostliny)
+*Phototrophic organisms: obtain chemical energy from light (mostly includes plants).
-*organotrofní organismy: získávají energii z chemických reakcí (např. živočichové).<br />
+*Organotrophic organisms: obtain energy from chemical reactions (eg animals).<br />
-Mezi těmito dvěma skupinami organismů existuje symbiotických vztah, který bychom mohli nazvat jako základní koncept metabolismu a bioenergetiky.
+There is a symbiotic relationship between these two groups of organisms, which could be referred to as the basic concept of metabolism and bioenergetics.
-<br />
-Fototrofní organismy za pomoci světelné energie staví z molekul vody a oxidu uhličitého cukry a kyslík, který zase slouží pro heterotrofní organismy, které cukry oxidují za pomocí kyslíku procesem vnitřního dýchání, což vede k produkci energie. Každý živý objekt potřebuje neustále přísun energie ze svého okolí nutný k životně důležitým procesům. Z hlediska bioenergetiky je podstatou těchto procesů přeměna jednoho druhu energie na jinou. Mezi poptávkou a nabídkou energie existuje stav rovnováhy. Rovnováha může být vychýlena oběma směry, tedy může nastat:<br />
-*organismus energii spotřebovává nebo v organismu nastává poptávka po zdroji energie (v tom případě převáží katabolické děje nad anabolickými), energie se produkuje
+Phototrophic organisms use light energy to construct sugars and oxygen from molecules of water and carbon dioxide. This in turn serves heterotrophic organisms, which oxidize sugars with the help of oxygen through the process of internal respiration, leading to the production of energy. Every living object constantly requires a supply of energy from its surroundings for vital processes. From a bioenergetics perspective, the essence of these processes is the transformation of one type of energy into another. There is a state of balance between the supply and demand of energy.
-*organismus má příjem energie větší než výdej – dochází k hromadění energie a nabídka je větší než poptávka. Organismus se s takovým množstvím nadbytku musí nějak vypořádat, jinými slovy – musí ji uskladnit.<br /><br />
-==Podstata ukládání energie v buňce==
+The balance between anabolic and catabolic processes can vary in both directions over time, and the following cases can occur:<br />
-Můžeme si jej pěkně znázornit na příkladu zpracování potravy organismem po příjmu. <br />
-Cukry, [[glukóza|glukosa]], se přivádí do jater, kde se asi polovina  přemění na [[glykogen]] a zbytek projde játry do krve. Bez účasti [[insulin]]u vstupuje glukosa do erytrocytů a CNS. Zde se dále metabolizuje za produkce energie. Za spoluúčasti insulinu dále glukosa vstupuje do buněk kosterního svalu. Zde se buď spotřebovává nebo se ukládá ve formě glykogenu jako zásoba energie. Po překročení kapacity jater pro syntézu glykogenu se glukoza přeměňuje na [[triacylglyceroly]] a ukládá se do zásoby energie v tukové tkáni.<br />
+*The organism consumes energy or there is a demand for an energy source in the organism. Energy is produced as catabolic processes prevail over anabolic ones
+*The organism's energy intake is greater than its output - energy accumulates and the supply is greater than the demand. The organism has to somehow deal with such an amount of excess, in other words - it has to store it (meaning anabolic processes will prevail over catabolic one).<br /><br />
-[[Aminokyseliny]] (vznikají rozkladem proteinů) jsou rovněž přiváděny krví do jater i do ostatních tkání. V játrech a ostatních tkání slouží jako základní stavební kameny pro syntézu proteinů a dalším jsou vazbou na specifické nosiče transportovány do krve. V organismu není žádný orgán, který by sloužil jako zásobárna aminokyselin nebo dusíku. Proto je nadbytek aminokyselin odbourán převážně na glukozu a dusíkatý zbytek se vyloučí jako [[močovina]]. <br />
+==The essence of energy storage in the cell==
+This concept can be illustrated nicely using the example of food processed by the organism after intake. <br />
-[[Lipidy]] se do krve dostávají jako chylomikra přes [[Obecná anatomie mízního systému|lymfatický systém]]. Ve vazbě na specifické proteiny jsou transportovány krví a vychytávány tkáněmi pro potřebu metabolismu anebo transportovány do tukové tkáně, kde jsou uskladněny.
+The sugars, or glucose, is brought to the liver. About half of the substance is converted into glycogen while the rest passes through the liver into the blood. Glucose enters erythrocytes and the CNS. This is done without the need for [[insulin]] and glucose is then further metabolized there to produce energy. The remaining glucose also enters skeletal muscle cells, although it requires the aid of insulin in this case. Here it is either consumed or stored in the form of glycogen as an energy reserve. After the liver's capacity for glycogen synthesis is exceeded, glucose is converted into triacylglycerols and stored as an energy reserve in adipose tissue.<br />
-===Metabolismus živin po jídle===
+Amino acids (created by the breakdown of proteins) are also transported by the blood to the liver and other tissues. In the liver and other tissues, they serve as basic building blocks for protein synthesis, with others being transported into the blood by binding to specific carriers. There is no organ in the organism that serves as a reservoir of amino acids or nitrogen. Therefore, the excess of amino acids is mainly broken down into glucose, and the nitrogenous residue is excreted as urea.<br />
-Jestliže se po jídle oddáme zažívání vleže a v klidu, potom se největší část živin převedených do organismu přemění na zásobní tuky. Zejména nastává po překročení kapacity pro syntézu glykogenu (v játrech a svalech). Další nadbytečná glukoza (ať již přijatá v čisté formě glukozy nebo látky přeměněné na glukozu sekundárně) se ukládá ve formě triacylglycerolů do tukové tkáně. Děje se to proto, že v buňkách převládá koncentrace [[ATP]] nad ADP (nekoná-li se práce, nespotřebovává se ATP) a jak proces [[glykolýza|glykolýzy]], tak proces aerobní fosforylace jsou za tohoto stavu velmi zpomaleny.<br />
-Jestliže se však po jídle začne vyvíjet pracovní (motorická) aktivita, pak se způsob přeměny živin podstatně mění. Nastane především využívání živin jako zdroje energie. Tyto zásoby primárně využitelných živin se spotřebují a teprve potom může dojít k odbourávání zásob energie, která si buňka uložila do zásoby především tuků – tedy zásobních triacylglycerolů z tukové tkáně.<br />
-==Odkazy==
+Lipids enter the blood as chylomicrons via the lymphatic system. When associated with specific proteins, lipids are transported by the blood and absorbed by tissues for metabolic needs or transported to fat tissue, where they are stored.
-===Použitá literatura===
-*Biochemie v obrazech a schématech; Prof. MUDr. RNDr. Jan Musil, DrSc., Avicenum 1990<br />
+===Postprandial nutrient metabolism===
-*Harperova biochemie; Murray K. Robert, Daryl K. Granner; nakl. HaH, 2002
+If a person is lying down and at rest after a meal, the largest part of the nutrients transferred into the body will be converted into stored fats during digenstion. In particular, it occurs after exceeding the capacity for glycogen synthesis (in the liver and muscles). Additional excess glucose (whether received in the pure form of glucose or substances converted into glucose secondarily) is stored in the form of triacylglycerols in adipose tissue. This happens because the concentration of ATP prevails over ADP in the cells (if no work is done, no ATP is consumed) and both the process of glycolysis and the process of aerobic phosphorylation are greatly slowed down in this state.<br />However, if motor activity begins to develop after a meal, then the way nutrients are transformed changes significantly. Nutrients will primarily be used as a source of energy. These reserves of primarily usable nutrients are used up and only then can the energy reserves, which the cell has stored in a reserve of mainly fats – i.e. reserve triacylglycerols from adipose tissue, be depleted.<br />
-[[Kategorie:Biochemie]]
+==Links==
+===References===
+*Biochemistry in pictures and diagrams; Prof. MD RNDr. Jan Musil, DrSc., Avicenum 1990<br />
+*Harper's Biochemistry; Murray K. Robert, Daryl K. Granner; Publishing house HaH, 2002
+[[Category: Biochemistry]]