Category: Study Materials
-
Resveratrol: Benefits, Side Effects, Uses, and Dosage
Continue ReadingResveratrol Introduction
Many of the compounds are found in the natural resources like fruits and its products which gives abundant of nutrient to our body and whereas few of them can also be used as the source of the medicines. On the other hand, few has its own side effects.
Resveratrol is one of the compounds which is found in red grapes and its products like juice or wine, which is very helpful for hay fever and it also deals with weight loss. Resveratrol has many effects in the bogy including those of expanding the blood vessels and in clotting the blood.
This also helps in treating the pain and swelling and also helps in reducing the sugar levels in the blood and it also helps the body to fight against infections. This compound, Resveratrol is usually used in dealing with many conditions like high cholesterol, cancer and heart disease and also in curing many abnormal conditions in the body.
What is Resveratrol?
Resveratrol is one of the natural compounds that is found in the skin of the red grape, in peanuts, and in berries like blue berries. Resveratrol is considered as one of the most powerful antioxidants which is produced by some species of plants to protect them against the environmental stresses.
These antioxidants help in neutralizing the free radicals, that are believed to decline the symptoms of aging. Japanese knotweed is one of the species of plant which has the highest source of resveratrol content. Large amount of the resveratrol is produced in the skin of the red grapes which helps the plant to protect it from various kind of fungal diseases and protecting the plant and fruits from skin diseases and sun radiations. It is therefore considered that grapes have a higher amount of resveratrol in it comparing it with other natural food materials.
However, red wine consists of a small amount of resveratrol which is less than 1 to 2 milligrams per eight ounces of red wine. But on the other hand, red wine contains more resveratrol comparing with the white wine as these red wines are fermented along with the skin of the red grapes than that of the white wine.
Thus, a greater number of antioxidants that includes resveratrol which are naturally present in the skin of the grapes are extracted to form a wine. This is also found in seeds and in pomace of the grapes. Grapes that have been grown in humid environments contains more amount of resveratrol than in grapes which are grown in arid areas. Resveratrol is also been very responsible for lowering the rate of the heart diseases in French populations comparing to that of the other populations.
Resveratrol is also found in many of the dietary supplements which are extracted from the grape seeds and the Japanese knotweed to form the red wine. Where as the most of the supplements that are found in the market is usually derived from the Japanese knotweed as this plant is considered as one of the highest concentrations of the resveratrol, found naturally.
However, the amount and the purity of the resveratrol in the supplements varies widely. Now-a days micronized resveratrol is available which is found in the form of powder or in pills. Resveratrol has a low systemic bioavailability and it is not well absorbed orally. This process of microionisation greatly reduces the average particle size of the compound. Resveratrol is also available in the form of solution or as transdermal patch.
How Resveratrol Works?
First of all, Resveratrol protects the DNA of the cell, it is considered as one of the powerful antioxidants, which prevents the cell damage that are caused by free radicals. Free radicals are one of the unstable atoms that are caused due to pollution, sunlight and where as the bodies, burning fat leads to cancer and other aging problems.
Resveratrol Benefits
Resveratrol has many of the health benefits like protecting the heart and the circulatory system, lowering the cholesterol and it also helps to protect the body from heart attacks, stroke, clots.
It also acts as an antioxidant and helps us to lower the blood sugar levels and it also reduces the risk of various cancers.
Resveratrol greatly increasing on the heart disease, people who consume higher amounts of the dietary resveratrol have a lower risk of heart diseases.
People who take resveratrol orally does not improves the levels of cholesterol or the blood cholesterol which are known as triglycerides.
The grouping of symptoms sometimes increases the risk of diabetes and the heart diseases.
They also build up a fat in the liver, when drinking little or no alcohol.
Resveratrol Side Effects
Patients having disorders in the blood, results in bleeding on consuming resveratrol.
Women who are pregnant or under breast feeding should not consume resveratrol.
Resveratrol has its mild estrogenic activities, women with cancers is more sensitive to estrogenic activities.
Resveratrol reduces the activity of the enzymes that are involved in metabolizing the drugs.
Resveratrol Citations
Share
Similar Post:
-
Disaccharide: Definition, Structure, and Examples
Continue ReadingCarbohyderate and Disaccharide
Carbohydrates are one of the organic molecules that are made up of carbon hydrogen and oxygen in the ratio of 1:2:1. These are considered as the major classes of the biomolecules which serves as an important source of an energy. These compounds also play a role in serving as the structural components. Carbohydrates are generally classified into two major groups as simpler carbohydrates and the complex carbohydrates.
Simpler carbohydrates are also known as simple sugar which can be easily digested and it can also be served as the rapid source of energy. Whereas the Complex carbohydrates like cellulose, starch and glycogen takes more time to get digested and metabolized as they are high in fiber unlike simple carbohydrates as they are less likely to cause spikes in the blood sugar.
What are Disaccharide?
The term disaccharide generally refers to the two molecules of monosaccharides. A saccharide generally refers to the structural unit of the carbohydrates. Hence, disaccharide is a compound of carbohydrate which is made up two units of monosaccharides. The term sugar can be referred to as both Monosaccharides and disaccharides.
Monosaccharides are also known as simple sugars as they form the most fundamental type of sugar which is generally known as sucrose. Where as the term table sugar refers to the granulated form of sugar which is referred to as the sucrose. Disaccharide is made up of two monosaccharides namely glucose and fructose.
Characteristic of Disaccharide
Like carbohydrates, disaccharides are also made up of molecules like carbon, hydrogen and oxygen in the ratio of 2:1 which are then referred to as the hydrates of the carbon. Disaccharide are the organic compounds which are linked together by a covalent bond. Disaccharides are the sugar base that comprises of two molecules of monosaccharides that are linked together by a glycosidic bond. Monosaccharides are considered as the most fundamental compound of the carbohydrate.
Glycosidic bonds are considered as the covalent bonds which are formed by two hydroxyl groups having two monosaccharides. Though disaccharides are made up of same chemical formula they are classified into three different kinds however they differ in bond formation and they constitute different properties.
However, disaccharides vary from the other forms of carbohydrates, oligosaccharides and the polysaccharides which all make up the unit of the sugar. Thus, disaccharides are made up of two monosaccharides and the oligosaccharides are made up of three to ten molecules of monosaccharides. Whereas the polysaccharide is made up of several units of monosaccharides.
Disaccharide Synthesis
The chemical process in which the monosaccharides are joined together are known as dehydration synthesis as it results in release of the byproduct, water. Disaccharides are generally formed by displacing a molecule of hydroxyl from the one monosaccharide and the proton taken form the other molecules of monosaccharide.
Thus, formation of two monosaccharides linked together by a covalent bond. Further the proton and the hydroxyl groups are detached and joined to form a water molecule. Thus, disaccharides are formed by the condensation process of two monosaccharide molecules.
Disaccharide is reverted into the monomeric components of monosaccharides by the process of hydrolysis along with the helps of an enzyme disaccharidase. Whereas the condensation process involves the elimination of the water, where it is utilized by the process of hydrolysis.
Classification of Disaccharide and Disaccharide Examples
Disaccharides are generally classified into two types namely reducing and the non-reducing.
A reducing disaccharide is one of the types of disaccharide in which the reducing sugar contains a free hemiacetal unit which serves as the reducing aldehyde group. Examples of one such reducing disaccharide is maltose or cellobiose.
On the other hand, the Non-reducing disaccharides are the ones which do not act as a reducing agent. Both monosaccharides which makes up the molecule of disaccharide does not have hemiacetal unit as they bond through the linkage of the acetal between the anomeric centers. Examples of such non-reducing disaccharides are sucrose and the trehalose.
Importance of Disaccharide
Dietary disaccharides are the other form of carbohydrates which serves as a source of energy. As we intake and digest the disaccharides they are break down into units of monosaccharides which play an important role in metabolizing them for synthesizing the ATP molecules and thus generating the energy. ATPs are thus considered as the biologically synthesized molecules through the process of aerobic and anaerobic respiration.
Glucose is considered as one of the most common form of monosaccharide, where the cellulitis’s the synthesized ATP through the substrate level of phosphorylation. Whereas one of the sources of glucose is disaccharide which contains diet.
However, too much of glucose is considered as hazardous as too much of glucose and leads to diabetes and the obesity risks, and other issues like cardiovascular diseases and formation of tooth decay.
Lactose is one of the disaccharides which is found in the breast milk and it is considered as one of the most important nutrient sources for the infants. Where as the micro-organisms like Lactobacilli has its ability to convert lactose into lactic acid, which is used in the food industry for the production of diary products like yogurt and cheese. The other form of disaccharide named maltose is generally used as a sweetener even it is less in its sugar source.
Disaccharide Citations
- Disaccharide structure code for the easy representation of constituent oligosaccharides from glycosaminoglycans. Nat Methods . 2008 Apr;5(4):291-2.
- The clinical significance of disaccharide maldigestion. Am J Clin Nutr . 1994 Mar;59(3 Suppl):735S-741S.
- Disaccharide digestion: clinical and molecular aspects. Clin Gastroenterol Hepatol . 2006 Mar;4(3):276-87.
Share
Similar Post:
-
Monosaccharide: Definition, Structure, and Examples
Continue ReadingMonosaccharide Introduction
We all know that our composed is composed of many of the organic compounds, which makes our cells to function efficiently by restoring the energy and its components that synthesis energy rich molecules. One such compounds are monosaccharides which is one of the compounds of the carbohydrate or it may also be referred to sugar A simple sugar which contains the building blocks of a complex forms of the sugar like oligosaccharides and the polysaccharides.
Sugar molecules play an important role in every organism as they help in formation of a glucose which then reduces and undergoes various process to form a molecule of ATP (Adenosine Triphosphate) which are known are considered as the basic energy supplements of our body. However, the term monosaccharide refers to the one saccharide. A saccharide is one of the structures of the carbohydrate. Hence, monosaccharide refers to the carbohydrate that has only one unit of saccharide.
Monosaccharide
Generally, the term sugar refers to both the monosaccharides and the disaccharides. Monosaccharides are thus a simple molecule of sugar as they are considered as one of the significant kinds of sugar. Which does not mean the table sugar or granular sugar, those which are considered as the sucrose’s. Because sucrose’s are the disaccharide molecules, that is it is made up of two monosaccharides named glucose and fructose, which are all come under the group of carbohydrates. Carbohydrates are one of the organic compounds that are made up of carbon, hydrogen and oxygen in the ratio of 1:2:1. These are considered ad one of the major biomolecular compounds, which are the important sources of the energy which also in turn serve as the structural components.
Monosaccharide Features
One of the most fundamental and the common type of sugars known as monosaccharides, which means that they cannot be separated or broken down into any other simpler compounds rather than hydrolysis. Where as monosaccharides has the capability of combining with the other complex types of molecules.
Monosaccharides are usually joined together with the help of a glycosidic bond, which are also known as glycosidic linkages. These glycosidic bonds are considered as the covalent bonds. Thus, the combination of the two simple sugars then refers to as disaccharide, Other molecules which consisting of about three to ten molecules of sugar are called as oligosaccharides.
Apart from them the molecules consisting of about large number of monosaccharide units are referred to as polysaccharides. Where as the chemical process which is involved in combing the molecules of the monosaccharides are known as dehydration synthesis as it results in releasing the water as its by-product. Though this process is irreversible, the complex carbohydrates are broken down into simple sugars, like glycogenolysis where the glycogen is being broken down into the units of glucose which is used further in the energy metabolism processes.
Monosaccharides are usually a colourless and a crystalline substance which are sweet in taste and a solid component. These substances are easily soluble in water. Now a days it occurs in the form of liquid sugars or syrups. However, like other carbohydrates, monosaccharides are also considered as one of the organic compounds and contains carbon which is covalently bonded with the other atoms like hydrogen and oxygen.
Role of Monosaccharide
Monosaccharides play a very important role in performing various kinds of functions. One of the important functions is that it serves as a structural and the multifunctional biological unit. With the help of the glycosidic bonds, they join together and form a complex oligosaccharides and other polymers namely cellular, starch and glycogen. It also serves as a precursor for many other compounds and its formations like galactosamine, glucosamine, sulfoquinovose, mannitol, glucuronic acid and so on.
Monosaccharides are similar to those of other carbohydrate molecules which plays an important role in supplying the nutrition. Monosaccharides are also found in natural sources like fruits, vegetables and other dietary nutritional supplements. Where these are consumed for the purpose of deriving energy in the form of ATP which acts as the biofuel and other sources of minerals. Glucose is one of the most common form of monosaccharide which helps us to synthesize ATP through the levels of phosphorylation reactions.
Classification of Monosaccharide
According to the biochemistry monosaccharides are classified into three types as follows,
Depending on the placement of the carbonyl group.
Number of carbon atoms it contains.
Depending upon its chiral handedness.
Monosaccharide and Metabolic Pathways
Monosaccharides play an important role in many of the metabolic pathways in our body and they are listed below.
Glycolysis: Here the monosaccharide is converted into pyruvate which release a high amount of energy biomolecules.
Pentose Phosphate Pathway: It is one of the alternative pathways for breaking the glucose molecules.
Glyconeogenesis: Here the non-carbohydrate precursors will be converted into monosaccharides.
Glycogenolysis: Here the glycogen is converted into monosaccharide units.
Glycogenesis: Here the glycose is being converted into glycogen.
Monosaccharide Citations
- Role of monosaccharide transport proteins in carbohydrate assimilation, distribution, metabolism, and homeostasis. Compr Physiol . 2012 Apr;2(2):863-914.
- Physiology, Carbohydrates. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan. 2021 Jul 26.
- Monosaccharides in health and disease. Annu Rev Nutr . 1986;6:211-24.
- Essentials of Glycobiology [Internet]. 3rd edition. Cold Spring Harbor (NY): Cold Spring Harbor Laboratory Press; 2015-2017.
Share
Similar Post:
-
Osmosis: Definition, Mechanism, and Examples
Continue ReadingWhat is Osmosis?
The movement of water molecules across semi permeable membrane to produce a homeostatic system in cell and its environment is the process of osmosis.
Characteristic of Osmosis
Osmosis was derived from Latin which means impulse or urge; of the solvent to move uphill from lower concentration to higher concentration. The main difference between osmosis in living and non – living cells are the properties of the particular system. Osmosis in non – living cells can be demonstrated by separating the solution and water by a semipermeable membrane.
Osmosis is a type of diffusion between a solution and water when separated by a biological membrane which is permeable for solvents and restrict the entry of solutes.
Fick’s law can be theoretically applied to the diffusion where the rate of diffusion is directly proportional to the concentration gradient and area over the diffusion occurs. Experiments are done to depict the mechanism of osmosis in a living tissue where a solution and pure solvent present in two chambers A and B separated by a semi permeable membrane and observed from the initial time T. After a particular time say T’ to maintain a system equilibrium and restrain by the membrane the pure solvent enters the chamber A of solution to maintain the equilibrium. As the pure solvent enters Chamber A increasing volume of the chamber indicating the movement of the solvent from lower to higher concentration.
Osmosis Examples
Water is transported by vascular tissues xylem where the nonliving tracheid are also taking up the water. In leaves mesophyll cells; the tracheid’s opens to the cells and water enters cell via Osmosis. Semipermeable part of the cells is the plasma membrane. Plasma membrane along with cellular components are protoplast. The liquid part is called as the protoplasm and other cellular components (i.e.) organelles are also separated from each other by membranes. Plant cells are specialized by carrying a vacuole and cell wall both has its specific role in plants structure.
Additionally; plasma membrane is protective and regulative in nature by the mechanism of osmosis and presence of channels and transmembrane which transports particulate compounds for cellular metabolism. Further the plant is surrounded by Rigid Cell Wall which provides a particular shape for the cell.
Vacuoles – storage part of the cells stores nutrients and water in turn maintaining the internal volume of the cell. Externally the cells are connected by rigid cellulose made cell wall mediating communication between each other cells. Inside the cell wall they are separated from other cells by intercellular spaces.
Principle of Osmosis
Osmosis works on a basic principle of chemical potential difference between 2 components separated by a semi permeable membrane. Chemical potential is the free energy available per mole of the substance in a solution. In the osmosis demonstration the pure solvent had high energy compared to the solution which had lower energy (i.e.) lower chemical potential which created a gradient to pure solvent enter the Chamber A. The potential difference arises because of the solute in the cytoplasm which are part of energy metabolic activities constantly replenishes the chemical molecules and are dynamic in nature.
Semi permeable membrane does not allow solute molecules and solute or ion uptake is mediated by ATP utilizing carrier proteins knows as active transport breaking down ATP to produce energy for ion uptake. Active transport of ions constitutes a potential difference between an internal and external environment develops a chemical potential gradient taking up water molecules from xylem. This indicates for every active uptake of ion generates a potential difference involves a passive entry of water into the cell and thereby osmosis is indirectly coupled with energy utilization.
Osmosis is Pressure Dependent
Similar experiments can be quoted to prove the pressure during osmosis. Osmotic pressure is the maximal amount of pressure developed in a system separated by a semipermeable membrane by pure water. Pressure due to osmosis is demonstrated using an osmometer; where a thistle funnel is inverted and covered with a semipermeable membrane is separated by solution A and B; where A is pure solvent and B is solution. At time T’ osmosis happens and the volume of Solution B increases.
On attaching a piston and maintaining the same volume in osmometer by producing a pressure through a piston maintains volume constant for a particular time and when the pressure in piston is increased the water flow reverses from Solution A to Solution B. The pressure of the osmosis is directly dependent on the solute concentration. Dependent on solute concentration makes the process a colligative property of a solution along with 3 other properties.
Osmosis and Turgor Pressure
Turgor pressure or the phenomenon of turgidity is maintained by the process of osmosis; involves vacuoles, protoplast wherein the water uptake in vacuole produces a basic crispness in cell structure and additionally the protoplasm as a whole requires water to maintain rigidity of plant cell thereby making the whole plant stand erect. When a cell loses its water content the leaves and stem wilts and the state is flaccid and prolonged flaccid nature of plants leads to death. To retain the structure water uptake becomes essential which is mediated by osmosis.
Importance of Osmosis
• Partially; the water uptake from soils controlled by osmosis in roots.
• Facilitate water movement from non – living part to the living part of the plant.
• Mechanical support of rigidity is provided by osmosis.
• A special ability of osmosis allows a plant to be turgid and helps in movement of ions in plants.
• Osmotic pressure produces a growth in plants.
• Opening and closing of stomata, flower is done with the help of osmosis.
Osmosis Citations
- Forward osmosis membrane technology for nutrient removal/recovery from wastewater: Recent advances, proposed designs, and future directions. Chemosphere . 2021 Jan;263:128116.
- Forward osmosis membrane processes for wastewater bioremediation: Research needs. Bioresour Technol . 2019 Oct;290:121795.
- Measuring osmosis and hemolysis of red blood cells. Adv Physiol Educ . 2017 Jun 1;41(2):298-305.
Share
Similar Post:
-
Active Transport: Definition, Mechanism, and Examples
Continue ReadingAbout PhD In Psychology
Minerals and water are transferred from roots to the plant by passive forces of movement namely diffusion and facilitated diffusion; does not constitute to effective transport of the molecules into the cells. Regular metabolic functions require nutrients to enter the metabolic cycle of cells to produce energy for the plant physiological functions. Dynamic molecular movement inside cell and its organelles, between cells and between external environment and plants require other transport mechanism to tag along passive transport.
Active transport is an effective means of transportation of ions and molecule along transcellular pathway. Energy is utilized by the dephosphorylating energy currency of the cells produced by oxidative phosphorylation and Electron Transport Chain in mitochondria of every cell; is effective in transporting voluminous number of ions from the cells. The transport of ions actively involves movement against the gradient of ions and other nutrients constitutes a potential difference electrochemically for the movement of ions and other nutrients.
Movement of ions from cells to the extracellular space and back to cell is contributed by the potential difference between a cell and the external environment constituting a potential difference: Transmembrane potential across these; acts as a driving force for the transport of the ions and charged molecules.
Donan Equilibrium
Donan equilibrium explains the transmembrane potential difference because of the movement of charged ions and the equilibrium of the cell in electrochemical terms. The cell is dynamic and are negatively charged predominantly. Assuming high K+ concentration inside the cell; K+ movement is a simple diffusion or facilitated diffusion pertaining to the protein channels and concentration gradient; to maintain an equilibrium out of the concentration terms. But the mechanism of the cell and its ability not only involves the concentration gradient for the movement but are dependent on both electric and chemical potential difference.
Electrochemically, the K+ ion is coupled with respective cations; are attracted back to the cell by the negative charges. An equilibrium is achieved when the force of concentration gradient pulling the K+ ions outside the cells and electrical gradient pulling K+ inside the cells. Hence a Donan equilibrium is achieved and the mechanism is similar for most of the ions and molecules. Donan’s equilibrium is also termed as Gibbs – Donan equilibrium; as Gibb’s had the equation predicted long back before Donan’s discovery.
Carrier Concept in Active Transport
A general mechanism of movement of ions across the cell membrane mediated by energy dependent protein molecules is clearly explained by the carrier concept. The transmembrane proteins act as a mediator for the movement of ions by binding to the ions and release them to the external or internal membrane based on the requirement.
This mechanism takes place in 3 steps:
Initially, carrier molecules are activated by the dephosphorylating ATP mediated kinases.
Activation of carrier binds to the ion forms a carrier – ion complex
On release of the phosphatase the ions and the carrier molecules are released closing the membrane.
Two theories were put forth based on the carrier concept and are named as Ludegardh’s cytochronme theory and Bennet – Clark’s Hypothesis.
a). Ludegardh's Cytochrome Theory for Active Transport
Ludegardh’s cytochrome theory was formulated by Ludegardh and Burstrom in 1933, assumes 3 postulates. They are: Active transport of anion is present and cation is passively diffused and are independent of anions. Anions are transported through cytochrome system of electron transport chain. Cytochrome acts as a carrier. Oxygen gradient exists across the external and internal surface with oxidation at external surface moves the anion to the internal surface where the reduction takes place. Main disadvantage of the theory is that the carrier molecules present are presumed to transport the anions and cations are transported through passive diffusion.
b). Bennet - Clark's Hypothesis
Bennet – Clark’s Hypothesis proposed in 1956 involves ATP carrier mechanism; associates with phosphatide transport across impermeable membrane. The carrier transports both anion and cation making the protein molecule an “amphoteric” molecule.
Active Transport Types
Active transports are similar inside and across different cell species; mediated by special protein structures in transmembrane walls of the cell directly utilize energy to facilitate the movement of ions across the cell against the concentration gradient are termed as “PUMPS”. Other protein channels utilize energy produced by the potential difference for the movement. Based on this the Active transporters are divided into:
Examples of Active Transporters
Primary Active Transporters
Primary active transport includes movement of ions and nutrients across semi permeable membrane through carrier proteins powered by ATPase. ATPase are protein pumps which transports ions against contraption and electric gradient from inside to outside of the cell and vice versa. The carrier molecules are termed as pumps; facilitating the movement of ions against concentration gradient.
Active transport of ions is further classified as Electrogenic or electroneutral transport based on the potential difference created by the net movement of the ions. Electrogenic transport is well demonstrated by Na/K pump in humans where exit of 3 Na ions 2 K+ ions are taken in; resulting in net outward movement of positive charges making it electro genic.
Similarly, in contrast to Na/K pumps; H /K+ pumps are present where for every exit of H+ ion One K+ ion enters the cell results in a neutral potential difference across the cell membrane. This H+ /K+ ion pump is an example for electroneutral transport. In animals the principal ion in transport to maintain membrane potential is Na+ but in plants H+ ions play important role in movement across the membrane.
The primary transporters implants are predominantly present in Plasma Membrane is H+ ATPase, Vacuolar tonoplast has specialized Hiaasen H+ PP ase in Golgi cisternae also has similar active transport coupled with ATP molecules. Apart from K+ ions Ca+ ions are tyransported and regulated as they act as ligands in many transmembrane proteins. Further primary active transport protein pumps are classified based on their function at different parts of the cell.
Proton Pumps
H+/ ATPase pumps are predominant in plants where the outward transport of H+ ions constitute a potential gradient coupled by ATP utilization in most of the pumps but the H+ pump in chloroplast utilizes light as a source of energy to drive the ATP synthesis. Proton pump allows the transport of ion in single direction hence it is an uniport and are electrogenic.
Further based on their structure the H+ ATP pumps are classified as: F type, V type and P type.
• F type is present in thylakoid membrane utilize the energy created by the potential difference across the membrane to synthesis ATP.
• P Type is the ATP ase present in the Plasma membrane dependent on Mg; drives one H+ ions outside the cell on ATP dephosphorylation.
• V Type is present in the vacuoles of the cells are similar to F type are specialized in making the vacuoles acidic to the plasma membrane pH due to the accumulation of organic and inorganic anions.
Ca Pumps
Ca+ pumps are similar to ATP as present in P type pump in the plasma membrane having a polypeptide chain of about 110kD with extended N – Terminal domain. On Hydrolysis of ATP; 2 Ca+ ions are transported across the membrane regulating the Ca+ ions in cytosolic pool as excess of Ca+ in the cytoplasm may mediate many enzymes activity. Ca binds with calmodulin has inhibitory effects in Ca pump acts as a negative feedback loop to release excess of Ca to external environment.
H+ Pyrophosphatase Pump
ABC Transporters: ATP Binding Cassette Transporters are largest protein molecules found in living organism are similar to P type channels. These are not electrogenic transporters which are involved in nutrient uptake in plasma membrane and takes up molecules for storage in vacuoles. They mainly transport uncharged substances out of cell without any changes in charge and electrochemical gradient.
Secondary Active Transporters
Secondary active transporters are indirect active transporters which utilize the proton motive force created by the H+ gradient to move other minerals and nutrient uptake as the direct active transport moves H+ or Ca+ outside the cell. Secondary transporters involve Symport and Antiport where respective proteins present in the membrane facilitates the transport of the molecules.
Symport involves the movement of molecules and nutrient uptake on same direction involves H+ ions move against the protein gradient. Antiport as the name indicates the H+ ions move against its gradient is coupled with opposite directional movement of mineral or nutrient to be transported. Active Transport includes the transport of ions and nutrients. ATPase in cell membrane is high in number and are varied in action.
Active Transport Citations
Share
Similar Post:
-
Imbibition: Definition, Mechanism, and Examples
Continue ReadingImbibition Definition
Imbibition refers to the movement of water molecules absorbed by any living or dead material of plant by joint action of capillary and electrostatic force. Imbibition is a passive process without conversion of metabolic products or energy utilized.
Features of Imbibition
Seed germination completely depends on radicle formation and imbibition of seeds by water; Cellulose, hemicellulose, pecten and other proteinaceous hydrophilic substance of the dry seed swells when subjected to water. Significant adaptation of plant to produce dry seed is to protect from the harsh condition germination where it causes death to their progeny.
Apart from seed germination; imbibition plays a small role in transfer of water and nutrition in plants; by its ability to move the water over a very small distance. Transport over large distance is dependable on the species of plants and are explored less.
Imbibition along with other passive forces also contributes to water transport in root hairs. The phenomenon is easily understood; as a dead tree trunk in water swells voluminously is the exact mechanism of uptake of water by imbibition. The volume of the imbibant (i.e.) cellulose or hemicellulose, pecten increases the whole volume of the plant or the trunk does not increase because of the rearrangement and reorientation of the water molecules attachment to the imbibant makes water to obtain less volume.
Main difference between a diffusion and imbibition is that it involves a solid as an absorbing substance (i.e.) the solid substance is the imbibant ; developing higher pressure after absorption. Imbibition is more specific to Hydrophilic colloids to absorb or transport water; is irreversibly dependent on matric pressure which was once termed as imbibition pressure. The pressure is similar to osmotic pressure which is really high to even break a rock and removes the external hard seed coat facilitating germination of seed. Imbibition takes place in both living and dead parts of plant.
History of Imbibition
Imbibition is a regular process of water uptake in plants especially in trunk is derived from Latin word – imbibere which means to drink in. In Ancient times during pyramid construction in Egypt; Egyptians used to break stones using the technique of imbibition. The small trunk pieces are inserted in rock cervices and trunks are soaked with water. The trunks expand absorbing the water produces high pressure induces a force up to 1000 kPa to break open a rock.
Similarly, the imbibition is used to break skull sutures to operate surgery in brain in ancient days by “Witch Doctors”. Witch Doctors opens the skull by prior treatment of skull by soaked seeds which on germination opens the seed coat produces force to open the skull allowing to perform the surgery. Imbibition examples are well present in our day today life; where the wooden doors, windows or other wooden articles exposed to sun rain absorb water and swells; which disables the ability of wood to function properly.
Imbibition in Water Transport
Passive forces constitute movement of water from the soil to roots hairs of plants and constitutes short distance transport of water. Water from soil due to the difference in concentration gradient move from higher concentration to lower concentration.
Short distance transport is easily achieved by either of the physical forces or in combination. Later, the transpiration pull created use to the evaporation and active transport in intracellular protein structures also constitutes transport of materials and water throughout the length of the plant.
Imbibition in Seed Germination
Water becomes essential for a seed to germinate at favorable environmental condition. Seeds undergo dehydration and rehydration process for germination. Once the seed is matured the water content of the seeds are given out by dehydration where the storage and genetic material are intact enough to survive for few days. On favorable condition with water the seed imbibes water and swells because of absorption of water. This causes a pressure to build up which breaks the seed coat for the seed to germinate. Following imbibition, a heat is generated; which is essential to drive the metabolic activities for seed development; caused by the liberation of heat because of water absorption.
The developmental changes in seeds are:
• Releasing hydrolytic enzymes to digest and mobilize the reserves
• Cell division and cell enlargement is started again
• Respiratory pathways start
• Development proceeds to produce new plant.
Imbibition Condition
Process of Imbibition depends on the chemical and electrostatic forces and the colloidal substance available to take up water. These are the 2 main contains for imbibition to occur:
Water potential is necessary between the imbibant and the water. Generally, imbibition takes place when the potential difference between the substance is high like in plants; the cellulose and pecten are colloid which absorbs water and transfer the water content from the lower potential region to higher potential region. Water potential on a colloid must be lower for a water to be absorbed.
Affinity between imbibant and liquid is essential. Colloids such as cellulose, pecten have higher affinity to water than to ether
Factor Affecting Imbibition
Imbibition depends on both internal environment of plants and external factors of the environment.
Temperature: Imbibition increase with an increase in temperature. Higher temperature increases the rate of imbibition by the movement produced by the kinetic energy of the colloids or the imbibing molecules. This the main external environmental factor influencing imbibition. At lower temperature; the surface becomes stiffer for absorption and enter a dormant stage or die due to unfavorable conditions.
Osmotic Potential: Osmotic potential between the imbibant and the medium must be steeper for imbibition to occur consistently and effectively. Increase in solute concentration in water leads to less absorption of water which does not support the movement of water or the germination.
Imbibition Citations
- Measurement and Modeling of Spontaneous Capillary Imbibition in Coal. ACS Omega . 2020 Jun 12;5(24):14461-14472.
- Experimental Investigation on the Imbibition Capacity and Its Influencing Factors in Hydrate Sediments. ACS Omega . 2020 Jun 9;5(24):14564-14574.
- Studies on the molecular mechanisms of seed germination. Proteomics . 2015 May;15(10):1671-9.
Share
Similar Post:
-
Facilitated Diffusion: Definition, Mechanism, and Examples
Continue ReadingWhat is Facilitated Diffusion?
Active and passive transport are the 2 main transport mechanisms mediating commination between an environment and a plant in which organizing tissues are directly interconnected and respond to environmental changes directly. Lack of central organizing unit and control mechanism in lower organisms such as plants directly interact with the environment at cellular or tissue level massively depends on Active and Passive transports. In plants water is a main element of circulation and in assimilation of CO2 to sucrose; absorbed in root hairs Passive uptake of water – Diffusion and facilitated diffusion.
Facilitated diffusion – a modified mechanism of diffusion; involves membrane transporters to allow water and other molecules on difference between concentration and electrochemical gradient. In 1930, passive transport of water in cells were experimented by artificially creating a cell to understand the better transport mechanism; resulted in efficient flow of water and minerals through membrane transporters in facilitated diffusion rather than through lipid bilayers as in simple diffusion. Facilitated diffusion is bi – directional depending upon either concentration gradient and electrochemical gradient. At equilibrium, the rate of transport of net molecules of water or other elements is minimal or null.
Schematic Representation of Facilitated Diffusion
Facilitated Diffusion Characteristic
1. Specificity: Transmembrane proteins are frequent in between sets of lipid bilayer. Molecules of transport are permitted in specific transporter molecules depending upon the molecule that enters a cell.
2. Passive Nature: Transport through the channels does not require the conversion of ATP into ADP or AMP to power the movement of molecules from higher concentration to lower concentration.
3. Saturation Kinetics: Apart from the specificity and passive transport; driving force of the net movement of molecules depends on the concentration or the net number of molecules present between external and internal environment of cell.
Facilitated Diffusion Citations
Share
Similar Post:
-
Diffusion: Definition, Formula and Examples
Continue ReadingWhat is Diffusion?
Diffusion is a process of passive transport predominant in root transferring water, minerals, and nutrients from soil to root by the difference between concentration gradient between root hairs and the soil. Diffusion is passive without powered by energy molecules – ATP; takes place in the absence of barriers (i.e.) cell wall specifically in plants and other living tissues and becomes effective in free space over a short distance.
Diffusion is a random motion of molecules in a free space without barriers of the molecules. Molecules above absolute zero in motion has a kinetic energy with heat and diffusion is a random motion in system to attain an equilibrium and hence the diffusion is governed by thermal agitation. Moles, atoms, or any particles in random motion is a medium collide with each other changing their course of motion in other random direction is diffusion.
Diffusion Formula
Diffusion was quantitatively measured by Adolf Fick in 1880’s determining the rate of diffusion to be the difference in the concentration gradient. The law formulated from Fick’s derivation is the “Fick’s first law” from the given equation
Js = -Ds ΔCs / Δ x
Js is the density of the diffusion at a unit area per time known as Density Flux
D is the diffusion coefficient of a substance over a medium, a proportionality constant depends on the medium in which the substance diffuses.
– negative sign indicates the rate of diffusion moves down a concentration gradient.
ΔCs is the concentration of the diffusing molecule Diffusion is slow over longer distances. This can be determined from the first law where the average time taken for a particle to diffuse over a distance id determined by the square of the distance L by the Diffusion coefficient. t= L2/Ds,
Diffusion Citations
Share
Similar Post:
-
Cell, Electrochemical Cell, Diagram, and Structure
Continue ReadingWhat is Cells?
The device which convert electrical energy into chemical energy or chemical energy into electrical energy is called cell.
Types of Cells
Cells are of two types;
1. Electrochemical Cell
The cell which convert chemical energy into electrical energy is called electrochemical cell.
Eg: Daniell cell
Daniell Electrochemical Cell Diagram
2. Electrolytic Cell
The cell which convert electrical energy into chemical energy is called electrolytic cell.
Ex- electrolysis of NaCl.
o In electrolytic cell redox reaction takes place.
o In electrolytic cell non-spontaneous (ΔG = positive) reaction type is proceed.
o For this cell, the value ΔG is positive.
The Electrolysis of Molten NaCl
If H Cl solution is take place in electrolytic cell then the following reaction takes place at cathode and at anode
H CL ⇔ H+ Cl–
At cathode: H+ + e- → ½ H2(g)
At anode: Cl– → ½ Cl2(g) + e-
Electrochemical Cell Citations
- An electrochemical cell for in operando studies of lithium/sodium batteries using a conventional x-ray powder diffractometer. Rev Sci Instrum . 2014 Oct;85(10):104103.
- Electrochemical cell-based chip for the detection of toxic effects of bisphenol-A on neuroblastoma cells. Biosens Bioelectron . 2011 Mar 15;26(7):3371-5.
Share
Similar Post:
-
Electrolytes: Definition, Type, and Functions
Continue ReadingWhat are Electrolytes?
An electrolyte is a substance that produces an electrically conducting solution when dissolved in a polar solvent, such as water. The dissolved electrolyte separates into cations and anions, which disperse uniformly through the solvent. Electrolytes are essential minerals such as sodium, calcium, and potassium. Electrolytes play an important role in many key functions in the body.
Classification of Electrolytes
All electrolytes do not dissociate in same amount at all the given dilution. on the basis, electrolytes are divided mainly in two parts strong electrolytes and weak electrolytes.
i. Strong Electrolytes
Strong electrolytes are those substance which are completely ionized in their aqueous solution. Generally, this class contains strong acids , strong bases and salt of acid-base (strong), salts of strong acid-weak base and weak acid-strong base.
Eg: HCl , NaOH , NaCl , CH3COONa , NH4Cl etc.
These salts are completely dissociated at normal dilution.
ii. Weak Electrolytes
Weak electrolytes are those substances which are not completely dissociated in their aqueous solution and degree of dissociation increase with increase in solution.
Ionic part of weak electrolytes is called “degree of dissociation” or “degree of ionization”. It is denoted by α. This class contains weak acids, weak bases and salt of weak acid and weak base.
Eg: CH3COOH, H2CO3, H3BO3, NH4OH, Al(OH)3, CH3COONH4
Factors Affecting Electrolyte Conductance
The conductance depends upon the following factors;
a) Inter-ionic Attraction
If strong ionic attraction is present between the ions of solute then they do not dissociate easily, when they dissolve in solvent, due to this the value of conductivity become less. The energy released in ion-solvent reaction is called “salvation-energy” and if water is solvent then it is called ‘hydration energy’. So, if the amount of ion -ion attraction energy is more than ion-solvent attraction then electrolytes are taken in class of weak electrolytes.
b) Salvation of Ions
It depends on attractive forces present between ions and solvents, which are called “ ion-solvent interactions”. If this attractive force is very strong then ion becomes solvate in which the layers of solvent molecules are attached to ions and decrease its size. In this condition, the movement of ions towards electrode decreases, so the conductivity decreases.
c) Viscosity of Solvent
Viscosity of solvent depends on solvent-solvent interactions. Greater the attraction, greater is the viscosity of solvent, which decreases the conductivity .
d) Concentration of Solution
Concentration of solution is greater than concentration of electrolyte solution, lesser is the value of its conductivity. The amount of dissociation increases with the increase in dilution due to which, the conductivity of solution of electrolyte increases.
e) Effect of Temperature
The average kinetic energy of ions of electrolyte increases with increase in temperature, which increases the degree of dissociation of electrolyte. Hence, the amount of conductivity increases with increase in temperature.
Electrolytes Citations
- Investigation of the role of electrolytes and non-electrolytes on the cloud point and dye solubilization in antidepressant drug imipramine hydrochloride solutions. Colloids Surf B Biointerfaces . 2008 Aug 1;65(1):74-9.
- Electrolytes. Isha Shrimanker; Sandeep Bhattarai.
- Selection of an electrolyte to enhance the electrochemical decolourisation of indigo. Optimisation and scale-up. Chemosphere . 2005 Aug;60(8):1080-6.
Share
Similar Post:
