What is Absorption?

In biology, absorption refers to the procedure of absorbing or assimilating substances within cells or across tissues through the process of diffusion or Osmosis.

The absorption of substances into the tissue or cell usually occurs via the general area of the cells. The rate and method of absorption is dependent on various factors, including the amount of the substance, the surface area and time of contact, as well as the solubility of the substance. The substance it is taken into is referred to as absorbate while the substance that is taken into the absorbate is known as absorbent.

Absorption is triggered by the existence of empty spaces inside those molecules that make up the absorbent that are then filled by those molecules that absorbate. Absorption can occur without the use to the energy (diffusion) or by the use in the energy (active transportation).

Absorption is an endothermic procedure that causes the heat energy of the system is increased as it takes in new molecules. In the majority of cases of absorption, the solid substances dissolve in liquid phases and then get absorbed by cells or tissues. Absorption is a general process in which the material absorbed is evenly distributed across the absorbent, and consequently affects the whole system. Absorption is a common feature in every living and non-living system for the purpose of absorbing nutrients or to ensure the balance and concentrations of the substances on an area. Absorption is a result of interactions. absorbate and the absorbent are non-specific and physical. Furthermore, there are there are no chemical forces at play.

Examples of Absorption

Skin absorption

The process involves absorbing substances via the surface of skin, either directly on it or through circulation. Absorption of the skin is a way for the introduction of chemical substances into the body in the form of toxins or drugs. The absorption process within the skin is can be affected by several variables like the amount of substance, its duration, areas of contact, chemical’s solubility and the physical state that the skin. The absorption process within the body is an process that is passive which doesn’t require the expenditure of energy. The most significant function of skin absorption the application of medicines to the skin which permits a localized action which is distinct from ingestion or injection. However, the capacity of the skin’s capacity to absorb substances can also cause skin disorders such as dermatitis. Exposure to chemicals for a long time results to the absorption higher quantities of chemicals that can be detrimental to skin and body.

Intestinal absorption

The absorption of water and nutrients into circulation is among the main roles of the digestion system. The digestion process is an active process that is characterized through the expenditure of energy. The epithelium layer of the large and small intestines absorbs water and nutrients that is later absorbed by the circulatory system. Intestine, in contrast to skin, is a selective absorber of the substances, ensuring inflow of only vital substances.

Absorption refrigerators

Absorption refrigerators are a particular type of refrigeration that makes use of absorption to cool of the substances. The refrigerators are first able to evaporate the refrigerant liquid which is later taken up by another liquid to produce a low partial pressure. In the end, the refrigerant fluid is heated to eliminate the heat from the refrigerator. Absorption refrigerators are often employed for recreational vehicle (RVs) or caravans since they can run with propane rather than electricity.

What is Adsorption?

Adsorption is the process that involves adhesion of liquid molecules or gases to an area of solid.

This is because solid particles/surfaces to pull the molecules of gas and liquid to their surfaces after they are in contact with molecules. Adsorption is a phenomenon on the surface that causes molecules to make an adsorbate-like layer over the object of adsorption. The process of adsorption takes place due to the energy of the surface that facilitates the attachment through van der Wall’s forces, or through covalent bonds, based in the type of substance involved.

In physical adsorption , molecules are linked just by the Van der Wall force of attraction, and there is no specificity in the chemical process that exists among the molecules. In chemical adsorption however bonds are created between the adsorbate and the adsorbent. These bonds are unique to each adsorbate and adsorbent combination. Adsorption is used extensively in many separation techniques, such as Ion exchange chromatography and adsorption chromatography.

These processes permit to separate molecules through specifically transferring the molecules of their liquid phases onto surfaces on the solid adsorbent. Adsorption can also be utilized by viruses that attach onto the surface of the bacteria, or any other living organism, prior to the entry. The adsorption process is affected by a range of factors based on the characteristics of the compounds involved. Common factors are temperature, pressure, region of contact, as well as what is the relationship between the adsorbent as well as the adsorbate. Adsorption is always exothermic because it results in a reduction in the forces that remain that are exerted on the surface.

Examples of Adsorption

Adsorption of viruses

In the case of viral infections the initial step in replication of the virus is attachment and adhesion of the virus onto the surface of the living organism. Adsorption by the virus can be attained when the proteins that are specific to the capsid of the virus bind to receptors on the surface of the living organism. These interactions are extremely specific and play an important part in the process of replication. These interactions are chemical bonds which are formed between various proteins. Adsorption of viral adsorbents is influenced by changes in pH and the temperature that the surface is exposed to.

Adsorption chromatography

Adsorption Chromatography is a separation method that uses the principle of adsorption in the separation of different particles within a mixture. The affinity is determined by the adsorption of particles of the mixture to its stationary component, bonds form which aid to separate substances that have higher affinity and lower affinity. The particles of the mix traverse throughout the stationary phase, where the particles are able to adsorb onto empty spaces of the stationary layer. The molecules that have lower affinity simply go through the system, and are collected independently. The interaction that occurs between molecules and their stationary counterparts are specific to them and comprise mostly chemical bonds.

Differences Between Absorption and Adsorption – Absorption vs Adsorption

Base for comparison	Absorption	Adsorption
Definition	The process is absorbing or assimilating substances onto an area like cells or tissues via diffusion or the process of osmosis.	Adsorption is the process that involves bonding molecules made of liquids or gases to the surfaces of solid.
Phenomenon	Absorption is a mass phenomenon in which molecules of absorbate are introduced in the absorbent.	Adsorption is a phenomena on the surface that occurs when molecules attach onto the surface on which the adhering agent is.
Principle	Substances are absorbed into an absorbent because of the space available in the particles and also the shape of.	Substances are absorbed onto the surface of the adsorbent since the adsorbent contains empty spaces that promote an adhesion process of the particles on the surfaces.
Heat exchange	Absorption is an exothermic process in which energy is transferred by the external surface. The total power of an absorbent grows following absorption.	The process of adsorption can be described as an exothermic procedure because the surface’s energy reduces due to a decrease in the residual forces that the surface experiences.
Rate	Absorption occurs in a consistent manner.	Adsorption rates rises gradually until it attains equilibrium.
Bonding	The absorbent materials stay in the absorbent and do not have anything to do with chemical reactions with the absorbent.	The materials that are adsorbed remain connected to the adsorbent by the force of Van der Wall, or covalent bonds.
Temperature	Absorption isn’t dependent on the temperature of the system.	Adsorption is a temperature-dependent phenomenon.
Concentration	The amount of absorbate in the absorbent is uniform following absorption.	Adsorbate is focused on its surface than other components that make up the Adsorbent.
Separation	Absorbed substances can be divided into various phases based on their chemical interactions with phases.	Adsorbents are separated when passing a new material through the material’s surface that replaces the adsorbed material.
Application	Many living and non-living organisms use absorption. Living organisms like unicellular ones utilize absorption for taking in nutrients as well as water. Refrigerators, which are not living systems, use absorption to store cold.	Different living and non-living systems make use of the concept of adsorption. Viral living systems employ the concept of adsorption to facilitate attachment to microorganisms or bacteria. Adsorption chromatography and other separation processes employ the concept of adsorption in order to facilitate the separation of mixed substances.