A capsule is a type of solid pharmaceutical dosage form in which the drug is enclosed in a small shell or container, usually composed of gelatin or other suitable material. The shell serves to protect the drug from degradation, improve its stability and shelf life, and facilitate swallowing by making it easier to consume. Capsules come in various sizes and colors and can contain one or more drugs in powder, liquid, or solid form. They are typically administered orally but can also be used for other routes of administration, such as rectal or vaginal.

Drug compounding is the process of combining, mixing, or altering ingredients to create a customized medication to meet the specific needs of an individual patient. This can be done for a variety of reasons, such as when a patient has an allergy to a certain ingredient in a mass-produced medication, or when a patient requires a different dosage or formulation than what is available commercially.

Compounding requires specialized training and equipment, and compounding pharmacists must follow strict guidelines to ensure the safety and efficacy of the medications they produce. Compounded medications are not approved by the U.S. Food and Drug Administration (FDA), but the FDA does regulate the ingredients used in compounding and has oversight over the practices of compounding pharmacies.

It's important to note that while compounding can provide benefits for some patients, it also carries risks, such as the potential for contamination or incorrect dosing. Patients should only receive compounded medications from reputable pharmacies that follow proper compounding standards and procedures.

In the context of medical and health sciences, particle size generally refers to the diameter or dimension of particles, which can be in the form of solid particles, droplets, or aerosols. These particles may include airborne pollutants, pharmaceutical drugs, or medical devices such as nanoparticles used in drug delivery systems.

Particle size is an important factor to consider in various medical applications because it can affect the behavior and interactions of particles with biological systems. For example, smaller particle sizes can lead to greater absorption and distribution throughout the body, while larger particle sizes may be filtered out by the body's natural defense mechanisms. Therefore, understanding particle size and its implications is crucial for optimizing the safety and efficacy of medical treatments and interventions.

A drug carrier, also known as a drug delivery system or vector, is a vehicle that transports a pharmaceutical compound to a specific site in the body. The main purpose of using drug carriers is to improve the efficacy and safety of drugs by enhancing their solubility, stability, bioavailability, and targeted delivery, while minimizing unwanted side effects.

Drug carriers can be made up of various materials, including natural or synthetic polymers, lipids, inorganic nanoparticles, or even cells and viruses. They can encapsulate, adsorb, or conjugate drugs through different mechanisms, such as physical entrapment, electrostatic interaction, or covalent bonding.

Some common types of drug carriers include:

1. Liposomes: spherical vesicles composed of one or more lipid bilayers that can encapsulate hydrophilic and hydrophobic drugs.
2. Polymeric nanoparticles: tiny particles made of biodegradable polymers that can protect drugs from degradation and enhance their accumulation in target tissues.
3. Dendrimers: highly branched macromolecules with a well-defined structure and size that can carry multiple drug molecules and facilitate their release.
4. Micelles: self-assembled structures formed by amphiphilic block copolymers that can solubilize hydrophobic drugs in water.
5. Inorganic nanoparticles: such as gold, silver, or iron oxide nanoparticles, that can be functionalized with drugs and targeting ligands for diagnostic and therapeutic applications.
6. Cell-based carriers: living cells, such as red blood cells, stem cells, or immune cells, that can be loaded with drugs and used to deliver them to specific sites in the body.
7. Viral vectors: modified viruses that can infect cells and introduce genetic material encoding therapeutic proteins or RNA interference molecules.

The choice of drug carrier depends on various factors, such as the physicochemical properties of the drug, the route of administration, the target site, and the desired pharmacokinetics and biodistribution. Therefore, selecting an appropriate drug carrier is crucial for achieving optimal therapeutic outcomes and minimizing side effects.

Nanotechnology is not a medical term per se, but it is a field of study with potential applications in medicine. According to the National Nanotechnology Initiative, nanotechnology is defined as "the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications."

In the context of medicine, nanotechnology has the potential to revolutionize the way we diagnose, treat, and prevent diseases. Nanomedicine involves the use of nanoscale materials, devices, or systems for medical applications. These can include drug delivery systems that target specific cells or tissues, diagnostic tools that detect biomarkers at the molecular level, and tissue engineering strategies that promote regeneration and repair.

While nanotechnology holds great promise for medicine, it is still a relatively new field with many challenges to overcome, including issues related to safety, regulation, and scalability.

I'm sorry for any confusion, but "Platinum" is not a medical term. Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal.

However, in the field of oncology, platinum-based compounds are used as chemotherapeutic drugs. These include:

1. Cisplatin: This is a platinum-containing drug that is used to treat various types of cancers such as testicular cancer, ovarian cancer, bladder cancer, and others. It works by forming crosslinks with the DNA of cancer cells, which disrupts their function and leads to cell death.

2. Carboplatin: This is another platinum-based chemotherapy drug that is used to treat various types of cancers such as ovarian cancer, lung cancer, and others. It is less toxic than cisplatin but has similar mechanisms of action.

3. Oxaliplatin: This is a third platinum-based chemotherapy drug that is used to treat colon cancer and rectal cancer. Like the other two drugs, it forms crosslinks with DNA and disrupts cell function leading to cell death.

These drugs are not made of pure platinum but contain platinum compounds that have been synthesized for medical use.

Polysorbates are a type of nonionic surfactant (a compound that lowers the surface tension between two substances, such as oil and water) commonly used in pharmaceuticals, foods, and cosmetics. They are derived from sorbitol and reacted with ethylene oxide to create a polyoxyethylene structure. The most common types of polysorbates used in medicine are polysorbate 20, polysorbate 40, and polysorbate 60, which differ in the number of oxyethylene groups in their molecular structure.

Polysorbates are often added to pharmaceutical formulations as emulsifiers, solubilizers, or stabilizers. They help to improve the solubility and stability of drugs that are otherwise insoluble in water, allowing for better absorption and bioavailability. Polysorbates can also prevent the aggregation and precipitation of proteins in injectable formulations.

In addition to their use in pharmaceuticals, polysorbates are also used as emulsifiers in food products such as ice cream, salad dressings, and baked goods. They help to mix oil and water-based ingredients together and prevent them from separating. In cosmetics, polysorbates are used as surfactants, solubilizers, and stabilizers in a variety of personal care products.

It is important to note that some people may have allergic reactions to polysorbates, particularly those with sensitivities to sorbitol or other ingredients used in their production. Therefore, it is essential to carefully consider the potential risks and benefits of using products containing polysorbates in individuals who may be at risk for adverse reactions.

I apologize for any confusion, but "Enbucrilate" is not a medical term or a medication that I am aware of. It's possible that there might be some misunderstanding or misspelling in the term. If you have more context or information about where this term came from, I may be able to provide a more accurate and helpful response.

However, if you are referring to "bucrilate" which is a type of polymer used in some medical applications such as wound dressings, then it is a substance that can absorb large amounts of water and create a gel-like barrier between the wound and the outside environment, helping to keep the wound moist and promote healing.

If you have any further questions or concerns, please don't hesitate to ask.

Poloxamers are a type of triblock copolymer made up of a central hydrophobic chain of polyoxypropylene (poly(propylene oxide)) flanked by two hydrophilic chains of polyoxyethylene (poly(ethylene oxide)). They are amphiphilic molecules, meaning they have both hydrophilic and hydrophobic parts.

Poloxamers are often used in the pharmaceutical industry as drug delivery agents, emulsifiers, solubilizers, and stabilizers. They can form micelles in aqueous solutions above their critical micelle concentration (CMC), with the hydrophobic chains oriented toward the interior of the micelle and the hydrophilic chains on the exterior, interacting with the water molecules. This unique property allows poloxamers to solubilize drugs that are otherwise poorly soluble in water, improving their bioavailability.

Poloxamers have been studied for various medical applications, including as drug carriers for chemotherapy, diagnostic agents, and mucoadhesive materials. Some specific poloxamer compounds have been approved by the FDA for use in pharmaceutical formulations, such as Poloxamer 188 and Poloxamer 407.

In a medical context, poloxamers are not typically used as standalone treatments but rather as components of drug delivery systems or formulations.

Drug delivery systems (DDS) refer to techniques or technologies that are designed to improve the administration of a pharmaceutical compound in terms of its efficiency, safety, and efficacy. A DDS can modify the drug release profile, target the drug to specific cells or tissues, protect the drug from degradation, and reduce side effects.

The goal of a DDS is to optimize the bioavailability of a drug, which is the amount of the drug that reaches the systemic circulation and is available at the site of action. This can be achieved through various approaches, such as encapsulating the drug in a nanoparticle or attaching it to a biomolecule that targets specific cells or tissues.

Some examples of DDS include:

1. Controlled release systems: These systems are designed to release the drug at a controlled rate over an extended period, reducing the frequency of dosing and improving patient compliance.
2. Targeted delivery systems: These systems use biomolecules such as antibodies or ligands to target the drug to specific cells or tissues, increasing its efficacy and reducing side effects.
3. Nanoparticle-based delivery systems: These systems use nanoparticles made of polymers, lipids, or inorganic materials to encapsulate the drug and protect it from degradation, improve its solubility, and target it to specific cells or tissues.
4. Biodegradable implants: These are small devices that can be implanted under the skin or into body cavities to deliver drugs over an extended period. They can be made of biodegradable materials that gradually break down and release the drug.
5. Inhalation delivery systems: These systems use inhalers or nebulizers to deliver drugs directly to the lungs, bypassing the digestive system and improving bioavailability.

Overall, DDS play a critical role in modern pharmaceutical research and development, enabling the creation of new drugs with improved efficacy, safety, and patient compliance.

Chitosan is a complex carbohydrate that is derived from the exoskeletons of crustaceans, such as shrimp and crabs. It is made up of chains of N-acetyl-d-glucosamine and d-glucosamine units. Chitosan has been studied for its potential medical and health benefits, including its ability to lower cholesterol levels, promote weight loss, and help control blood sugar levels. It is also used in wound care products due to its antibacterial and absorbent properties. However, more research is needed to confirm these potential benefits and establish recommended dosages and safety guidelines.

Nanomedicine is a branch of medicine that utilizes nanotechnology, which deals with materials, devices, or systems at the nanometer scale (typically between 1-100 nm), to prevent and treat diseases. It involves the development of novel therapeutics, diagnostics, and medical devices that can interact with biological systems at the molecular level for improved detection, monitoring, and targeted treatment of various diseases and conditions.

Nanomedicine encompasses several areas, including:

1. Drug delivery: Nanocarriers such as liposomes, polymeric nanoparticles, dendrimers, and inorganic nanoparticles can be used to encapsulate drugs, enhancing their solubility, stability, and targeted delivery to specific cells or tissues, thereby reducing side effects.
2. Diagnostics: Nanoscale biosensors and imaging agents can provide early detection and monitoring of diseases with high sensitivity and specificity, enabling personalized medicine and improved patient outcomes.
3. Regenerative medicine: Nanomaterials can be used to create scaffolds and matrices for tissue engineering, promoting cell growth, differentiation, and vascularization in damaged or diseased tissues.
4. Gene therapy: Nanoparticles can be employed to deliver genetic material such as DNA, RNA, or gene-editing tools (e.g., CRISPR-Cas9) for the targeted correction of genetic disorders or cancer treatment.
5. Medical devices: Nanotechnology can improve the performance and functionality of medical devices by enhancing their biocompatibility, strength, and electrical conductivity, as well as incorporating sensing and drug delivery capabilities.

Overall, nanomedicine holds great promise for addressing unmet medical needs, improving diagnostic accuracy, and developing more effective therapies with reduced side effects. However, it also presents unique challenges related to safety, regulation, and scalability that must be addressed before widespread clinical adoption.

Skin absorption, also known as percutaneous absorption, refers to the process by which substances are taken up by the skin and pass into the systemic circulation. This occurs when a substance is applied topically to the skin and penetrates through the various layers of the epidermis and dermis until it reaches the capillaries, where it can be transported to other parts of the body.

The rate and extent of skin absorption depend on several factors, including the physicochemical properties of the substance (such as its molecular weight, lipophilicity, and charge), the concentration and formulation of the product, the site of application, and the integrity and condition of the skin.

Skin absorption is an important route of exposure for many chemicals, drugs, and cosmetic ingredients, and it can have both therapeutic and toxicological consequences. Therefore, understanding the mechanisms and factors that influence skin absorption is crucial for assessing the safety and efficacy of topical products and for developing strategies to enhance or reduce their absorption as needed.

Drug stability refers to the ability of a pharmaceutical drug product to maintain its physical, chemical, and biological properties during storage and use, under specified conditions. A stable drug product retains its desired quality, purity, strength, and performance throughout its shelf life. Factors that can affect drug stability include temperature, humidity, light exposure, and container compatibility. Maintaining drug stability is crucial to ensure the safety and efficacy of medications for patients.

Polyglycolic acid (PGA) is a synthetic polymer of glycolic acid, which is commonly used in surgical sutures. It is a biodegradable material that degrades in the body through hydrolysis into glycolic acid, which can be metabolized and eliminated from the body. PGA sutures are often used for approximating tissue during surgical procedures due to their strength, handling properties, and predictable rate of absorption. The degradation time of PGA sutures is typically around 60-90 days, depending on factors such as the size and location of the suture.

Photolysis is a term used in medical and scientific contexts to describe a chemical reaction that is initiated by the absorption of light or photons. In this process, a molecule absorbs a photon, which provides sufficient energy to break a bond within the molecule, leading to the formation of two or more smaller molecules or radicals. This phenomenon is particularly relevant in fields such as pharmacology and toxicology, where photolysis can alter the chemical structure and biological activity of drugs and other substances upon exposure to light.

Pharmaceutical chemistry is a branch of chemistry that deals with the design, synthesis, and development of chemical entities used as medications. It involves the study of drugs' physical, chemical, and biological properties, as well as their interactions with living organisms. This field also encompasses understanding the absorption, distribution, metabolism, and excretion (ADME) of drugs in the body, which are critical factors in drug design and development. Pharmaceutical chemists often work closely with biologists, medical professionals, and engineers to develop new medications and improve existing ones.

I'm sorry for any confusion, but "Polyesters" is not a medical term. It is a term used in materials science and textile industry to describe a type of synthetic fiber made from polymers characterized by the presence of ester groups in their main chain. If you have any questions related to medical terminology or concepts, I'd be happy to help with those instead!

Freeze-drying, also known as lyophilization, is a method of preservation that involves the removal of water from a frozen product by sublimation, which is the direct transition of a solid to a gas. This process allows for the preservation of the original shape and structure of the material while significantly extending its shelf life. In medical contexts, freeze-drying can be used for various purposes, including the long-term storage of pharmaceuticals, vaccines, and diagnostic samples. The process helps maintain the efficacy and integrity of these materials until they are ready to be reconstituted with water and used.

Lipids are a broad group of organic compounds that are insoluble in water but soluble in nonpolar organic solvents. They include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids. Lipids serve many important functions in the body, including energy storage, acting as structural components of cell membranes, and serving as signaling molecules. High levels of certain lipids, particularly cholesterol and triglycerides, in the blood are associated with an increased risk of cardiovascular disease.

Caveolae are small, flask-shaped invaginations of the plasma membrane that are abundant in many cell types, including endothelial cells, adipocytes, and muscle cells. They are characterized by the presence of caveolin proteins, which play a crucial role in their formation and function.

Caveolae have been implicated in various cellular processes, such as endocytosis, signal transduction, cholesterol homeostasis, and mechanoprotection. They can also serve as platforms for the assembly of signaling complexes and the regulation of various enzymatic activities.

The invaginated structure of caveolae allows them to interact with extracellular molecules and intracellular proteins, facilitating the exchange of materials between the plasma membrane and the cytosol. Dysregulation of caveolae function has been linked to several diseases, including cardiovascular disorders, cancer, and neurological conditions.

A nanocapsule is a type of nanoparticle that is characterized by its hollow, spherical structure. It is composed of a polymeric membrane that encapsulates an inner core or "cargo" which can be made up of various substances such as drugs, proteins, or imaging agents. The small size of nanocapsules (typically ranging from 10 to 1000 nanometers in diameter) allows them to penetrate cells and tissue more efficiently than larger particles, making them useful for targeted drug delivery and diagnostic applications.

The polymeric membrane can be designed to be biodegradable or non-biodegradable, depending on the desired application. Additionally, the surface of nanocapsules can be functionalized with various moieties such as antibodies, peptides, or small molecules to enhance their targeting capabilities and improve their stability in biological environments.

Overall, nanocapsules have great potential for use in a variety of medical applications, including cancer therapy, gene delivery, and vaccine development.

Coloring agents, also known as food dyes or color additives, are substances that are added to foods, medications, and cosmetics to improve their appearance by giving them a specific color. These agents can be made from both synthetic and natural sources. They must be approved by regulatory agencies such as the U.S. Food and Drug Administration (FDA) before they can be used in products intended for human consumption.

Coloring agents are used for various reasons, including:

* To replace color lost during food processing or preparation
* To make foods more visually appealing
* To help consumers easily identify certain types of food
* To indicate the flavor of a product (e.g., fruit-flavored candies)

It's important to note that while coloring agents can enhance the appearance of products, they do not affect their taste or nutritional value. Some people may have allergic reactions to certain coloring agents, so it's essential to check product labels if you have any known allergies. Additionally, excessive consumption of some synthetic coloring agents has been linked to health concerns, so moderation is key.

Transmission electron microscopy (TEM) is a type of microscopy in which an electron beam is transmitted through a ultra-thin specimen, interacting with it as it passes through. An image is formed from the interaction of the electrons with the specimen; the image is then magnified and visualized on a fluorescent screen or recorded on an electronic detector (or photographic film in older models).

TEM can provide high-resolution, high-magnification images that can reveal the internal structure of specimens including cells, viruses, and even molecules. It is widely used in biological and materials science research to investigate the ultrastructure of cells, tissues and materials. In medicine, TEM is used for diagnostic purposes in fields such as virology and bacteriology.

It's important to note that preparing a sample for TEM is a complex process, requiring specialized techniques to create thin (50-100 nm) specimens. These include cutting ultrathin sections of embedded samples using an ultramicrotome, staining with heavy metal salts, and positive staining or negative staining methods.

In the context of medical definitions, polymers are large molecules composed of repeating subunits called monomers. These long chains of monomers can have various structures and properties, depending on the type of monomer units and how they are linked together. In medicine, polymers are used in a wide range of applications, including drug delivery systems, medical devices, and tissue engineering scaffolds. Some examples of polymers used in medicine include polyethylene, polypropylene, polystyrene, polyvinyl chloride (PVC), and biodegradable polymers such as polylactic acid (PLA) and polycaprolactone (PCL).

Indomethacin is a non-steroidal anti-inflammatory drug (NSAID) that is commonly used to reduce pain, inflammation, and fever. It works by inhibiting the activity of certain enzymes in the body, including cyclooxygenase (COX), which plays a role in producing prostaglandins, chemicals involved in the inflammatory response.

Indomethacin is available in various forms, such as capsules, suppositories, and injectable solutions, and is used to treat a wide range of conditions, including rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, gout, and bursitis. It may also be used to relieve pain and reduce fever in other conditions, such as dental procedures or after surgery.

Like all NSAIDs, indomethacin can have side effects, including stomach ulcers, bleeding, and kidney damage, especially when taken at high doses or for long periods of time. It may also increase the risk of heart attack and stroke. Therefore, it is important to use indomethacin only as directed by a healthcare provider and to report any unusual symptoms or side effects promptly.

Medical definitions of water generally describe it as a colorless, odorless, tasteless liquid that is essential for all forms of life. It is a universal solvent, making it an excellent medium for transporting nutrients and waste products within the body. Water constitutes about 50-70% of an individual's body weight, depending on factors such as age, sex, and muscle mass.

In medical terms, water has several important functions in the human body:

1. Regulation of body temperature through perspiration and respiration.
2. Acting as a lubricant for joints and tissues.
3. Facilitating digestion by helping to break down food particles.
4. Transporting nutrients, oxygen, and waste products throughout the body.
5. Helping to maintain healthy skin and mucous membranes.
6. Assisting in the regulation of various bodily functions, such as blood pressure and heart rate.

Dehydration can occur when an individual does not consume enough water or loses too much fluid due to illness, exercise, or other factors. This can lead to a variety of symptoms, including dry mouth, fatigue, dizziness, and confusion. Severe dehydration can be life-threatening if left untreated.

A cell line that is derived from tumor cells and has been adapted to grow in culture. These cell lines are often used in research to study the characteristics of cancer cells, including their growth patterns, genetic changes, and responses to various treatments. They can be established from many different types of tumors, such as carcinomas, sarcomas, and leukemias. Once established, these cell lines can be grown and maintained indefinitely in the laboratory, allowing researchers to conduct experiments and studies that would not be feasible using primary tumor cells. It is important to note that tumor cell lines may not always accurately represent the behavior of the original tumor, as they can undergo genetic changes during their time in culture.

Endocytosis is the process by which cells absorb substances from their external environment by engulfing them in membrane-bound structures, resulting in the formation of intracellular vesicles. This mechanism allows cells to take up large molecules, such as proteins and lipids, as well as small particles, like bacteria and viruses. There are two main types of endocytosis: phagocytosis (cell eating) and pinocytosis (cell drinking). Phagocytosis involves the engulfment of solid particles, while pinocytosis deals with the uptake of fluids and dissolved substances. Other specialized forms of endocytosis include receptor-mediated endocytosis and caveolae-mediated endocytosis, which allow for the specific internalization of molecules through the interaction with cell surface receptors.

Cisplatin is a chemotherapeutic agent used to treat various types of cancers, including testicular, ovarian, bladder, head and neck, lung, and cervical cancers. It is an inorganic platinum compound that contains a central platinum atom surrounded by two chloride atoms and two ammonia molecules in a cis configuration.

Cisplatin works by forming crosslinks between DNA strands, which disrupts the structure of DNA and prevents cancer cells from replicating. This ultimately leads to cell death and slows down or stops the growth of tumors. However, cisplatin can also cause damage to normal cells, leading to side effects such as nausea, vomiting, hearing loss, and kidney damage. Therefore, it is essential to monitor patients closely during treatment and manage any adverse effects promptly.

Antineoplastic agents are a class of drugs used to treat malignant neoplasms or cancer. These agents work by inhibiting the growth and proliferation of cancer cells, either by killing them or preventing their division and replication. Antineoplastic agents can be classified based on their mechanism of action, such as alkylating agents, antimetabolites, topoisomerase inhibitors, mitotic inhibitors, and targeted therapy agents.

Alkylating agents work by adding alkyl groups to DNA, which can cause cross-linking of DNA strands and ultimately lead to cell death. Antimetabolites interfere with the metabolic processes necessary for DNA synthesis and replication, while topoisomerase inhibitors prevent the relaxation of supercoiled DNA during replication. Mitotic inhibitors disrupt the normal functioning of the mitotic spindle, which is essential for cell division. Targeted therapy agents are designed to target specific molecular abnormalities in cancer cells, such as mutated oncogenes or dysregulated signaling pathways.

It's important to note that antineoplastic agents can also affect normal cells and tissues, leading to various side effects such as nausea, vomiting, hair loss, and myelosuppression (suppression of bone marrow function). Therefore, the use of these drugs requires careful monitoring and management of their potential adverse effects.

Phospholipids are a major class of lipids that consist of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails. The head is composed of a phosphate group, which is often bound to an organic molecule such as choline, ethanolamine, serine or inositol. The tails are made up of two fatty acid chains.

Phospholipids are a key component of cell membranes and play a crucial role in maintaining the structural integrity and function of the cell. They form a lipid bilayer, with the hydrophilic heads facing outwards and the hydrophobic tails facing inwards, creating a barrier that separates the interior of the cell from the outside environment.

Phospholipids are also involved in various cellular processes such as signal transduction, intracellular trafficking, and protein function regulation. Additionally, they serve as emulsifiers in the digestive system, helping to break down fats in the diet.

Biological transport refers to the movement of molecules, ions, or solutes across biological membranes or through cells in living organisms. This process is essential for maintaining homeostasis, regulating cellular functions, and enabling communication between cells. There are two main types of biological transport: passive transport and active transport.

Passive transport does not require the input of energy and includes:

1. Diffusion: The random movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.
2. Osmosis: The diffusion of solvent molecules (usually water) across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
3. Facilitated diffusion: The assisted passage of polar or charged substances through protein channels or carriers in the cell membrane, which increases the rate of diffusion without consuming energy.

Active transport requires the input of energy (in the form of ATP) and includes:

1. Primary active transport: The direct use of ATP to move molecules against their concentration gradient, often driven by specific transport proteins called pumps.
2. Secondary active transport: The coupling of the movement of one substance down its electrochemical gradient with the uphill transport of another substance, mediated by a shared transport protein. This process is also known as co-transport or counter-transport.