Bio/Biochem

Complement System

A mechanism that includes set of proteins in the blood that complements the immune response, participating in opsonization, chemotaxis, cell lysis, and agglutination to destroy pathogens.

opsonization

* The process in the complement system where foreign particles are marked for phagocytosis.
* Antigens signal the presence of threats, and infected cells are tagged, while circulating pathogens with the same antigen are identified.

Chemotaxis

* The attraction and movement of macrophages to a chemical signal.
* Cytokines and chemokines attract macrophages and neutrophils to the site of infection, enhancing the destruction of pathogens and treating the infection effectively.

Cell Lysis

* The breakdown or destruction of the membrane of a cell.
* Proteins in the complement system puncture the membranes of foreign cells, weakening their ability to grow and stopping the spread of infection.

Agglutination

* The process of using antibodies to cluster and bind pathogens together in the same area.
* Immune cells then attack and weaken the infection.
* Other innate immune system cells continue to circulate throughout the body to locate any pathogens not clustered and bound for destruction.

granulocytes

* a type of white blood cell involved in the immune response.
* They are characterized by the presence of granules in their cytoplasm.
* The three main types are neutrophils, eosinophils, and basophils.
* formed in the bone marrow and are an important part of the body's defense against pathogens.

adaptive immunity

* the specific defense mechanism of the immune system.
* characterized by the ability to recognize and remember specific pathogens or antigens.
* developed over time and is highly adaptable to different types of pathogens.
* involves the activation of lymphocytes, such as T cells and B cells, which produce antibodies and target specific antigens.
* provides long-term protection against pathogens and is a key component of the immune response.

immunological memory

Adaptive immunity retains memory of previous encounters with pathogens, enabling a faster and more effective response upon re-exposure to the same threat.

cells in adaptive immune system

B and T cells

creation of B cells and function in adaptive immunity

* Naïve cells encounter antigens in the lymphatic system, initiating their maturation process.
* possess millions of unique surface antigen-specific receptors coded in the organism's DNA.
* When a cell finds an antigen matching its receptor, it divides into memory cells or effector cells (plasma cells).
* Express specialized receptors called cell receptors (CRs) involved in antigen binding and signaling pathways with other immune cells.

creation of T cells and function in adaptive immunity

* progenitor cells mature into cells in the thymus.
* cells express cell receptors (CRs) and either CD4 or CD8 receptors.
* CRs recognize antigens bound to Major Histocompatibility Complex (MHC) molecules (MHCI or MHCII).
* CD4 and CD8 receptors assist in cell recognition and activation based on MHCI or MHCII binding.

humoral immunity

* a type of adaptive immune response mediated by antibodies.
* involves the production and circulation of **antibodies** in the body's fluids, such as blood and lymph.
* **known as immunoglobulins, are produced by B cells in response to the presence of foreign substances called antigens.**
* plays a crucial role in defending against extracellular pathogens, such as bacteria and viruses, by neutralizing or eliminating them.
* contributes to immune memory, allowing for a faster and more effective response upon subsequent exposure to the same antigen.

cell-mediated immunity

* a type of immune response that involves the activation of T cells to fight against intracellular pathogens, such as viruses and certain bacteria.
* T cells recognize and destroy infected cells directly or release chemical signals to recruit other immune cells to the site of infection.
* It is an important component of the immune system and plays a crucial role in defending the body against infections.
* essential for maintaining the body's defense against intracellular pathogens.

innate immunity

* refers to the body's natural defense mechanisms that are present from birth.
* first line of defense against pathogens and does not require prior exposure to the specific pathogen.
* includes physical barriers like the skin and mucous membranes, as well as cellular components like phagocytes and natural killer cells.
* involves the release of chemical substances such as cytokines and complement proteins.
* provides immediate protection against a wide range of pathogens, but it is not specific to particular pathogens.

B cells

* a type of white blood cell that plays a crucial role in the immune system.
* responsible for producing antibodies, which are proteins that help to identify and neutralize foreign substances in the body, such as bacteria and viruses.
* derived from stem cells in the bone marrow and mature in the lymphoid organs, such as the spleen and lymph nodes.
* Once activated, they can differentiate into plasma cells, which produce and secrete large amounts of antibodies, or memory B cells, which "remember" the specific antigen and mount a faster immune response upon re-exposure.

T cells

* are a type of white blood cell that plays a crucial role in the immune system.
* produced in the bone marrow and mature in the thymus gland.
* responsible for recognizing and attacking foreign substances, such as viruses, bacteria, and cancer cells, in the body.
* They achieve this by binding to specific antigens on the surface of these foreign substances.
* help regulate the immune response by releasing chemical messengers called cytokines.
* different types including helper T cells, cytotoxic T cells, and regulatory T cells, each with its own specialized function.

immunosuppressors

* medications that suppress or weaken the immune system.
* commonly used in organ transplantation to prevent rejection of the transplanted organ.
* work by inhibiting the activity of immune cells, such as T cells and B cells, which are responsible for mounting an immune response.
* Some commonly used ones include corticosteroids, calcineurin inhibitors (such as cyclosporine and tacrolimus), and antimetabolites (such as azathioprine and mycophenolate).

miRNA expression patterns

refer to the levels of microRNA molecules in a cell or tissue.

small non-coding RNA molecules that play important roles in gene regulation. The expression patterns of miRNAs can vary across different cell types, developmental stages, and disease conditions. Studying miRNA expression patterns can provide insights into biological processes and help identify potential biomarkers or therapeutic targets. Various techniques, such as microarray analysis or RNA sequencing, are used to measure miRNA expression levels.

glomerular function

* filtration process that occurs in the glomerulus, a network of capillaries in the kidney.
* involves the filtration of blood to form urine, removing waste products and excess substances from the body.
* essential for maintaining fluid balance, regulating blood pressure, and excreting metabolic waste.

phosphodiester linkages

* chemical bonds that connect nucleotides in DNA and RNA molecules.
* form between the phosphate group of one nucleotide and the sugar group of another nucleotide.
* create the backbone of the DNA and RNA strands, providing stability and allowing for the transmission of genetic information.

glycosidic linkages

* covalent bonds that connect monosaccharides to form larger carbohydrates, such as disaccharides and polysaccharides.
* formed through a condensation reaction, where the hydroxyl group of one monosaccharide reacts with the anomeric carbon of another monosaccharide, resulting in the formation of an oxygen bridge.
* play a crucial role in the structure and function of carbohydrates, including energy storage (e.g., starch and glycogen) and cell recognition (e.g., glycoproteins and glycolipids).

biopsy specimen

* small sample of tissue taken from a living organism for examination and analysis.
* commonly used in medical diagnostics to determine the presence or nature of a disease or condition.
* typically obtained through a minimally invasive procedure, such as a needle biopsy or surgical biopsy.
* play a crucial role in guiding treatment decisions and monitoring the progress of a disease.

lymphocytes

* a type of white blood cell that play a crucial role in the immune system.
* responsible for recognizing and attacking foreign substances, such as bacteria, viruses, and cancer cells.
* three main types: T cells, B cells, and natural killer (NK) cells.
* T cells are involved in cell-mediated immunity, B cells produce antibodies, and NK cells destroy infected or abnormal cells.
* produced in the bone marrow and can be found in lymph nodes, spleen, and other lymphoid tissues throughout the body.

monocytes

* a type of white blood cell that plays a crucial role in the immune system.
* They are the largest type of white blood cell and are produced in the bone marrow.
* responsible for phagocytosis, which is the process of engulfing and destroying pathogens, dead cells, and other foreign substances.


* they help in initiating an immune response by presenting antigens to other immune cells.
* can differentiate into macrophages or dendritic cells depending on the signals they receive.

human renal cells

* the cells that make up the tissue of the kidneys.
* responsible for various functions, including filtration of blood, reabsorption of nutrients, and secretion of waste products.
* These cells play a crucial role in maintaining the body's fluid and electrolyte balance.

microbiome

* the collection of microorganisms, including bacteria, fungi, viruses, and other microbes, that live in and on the human body.
* plays a crucial role in various aspects of human health, including digestion, immune function, and even mental health.

butyrate

* a short-chain fatty acid that is produced by the gut bacteria during the fermentation of dietary fiber.
* serves as an important energy source for the cells lining the colon

propionate

a type of short-chain fatty acid.

commonly found in the human body as a metabolic byproduct of certain bacteria in the gut.

Acetate

* refers to the ion or ester derived from acetic acid.
* plays a crucial role in various metabolic pathways, including the citric acid cycle, fatty acid synthesis, and cholesterol synthesis.
* an important source of energy for cells and is involved in the production of ATP through cellular respiration.
* can also be converted into other molecules, such as acetyl-CoA, which is a key intermediate in many biochemical reactions.

gram positive

a group of bacteria that retain the crystal violet stain used in the Gram staining method.

They have a thick peptidoglycan layer in their cell wall, which gives them a purple color when stained.

include species such as Staphylococcus, Streptococcus, and Clostridium.

gram negative

* a group of bacteria that do not retain the crystal violet stain used in the Gram staining method.
* They have a thin peptidoglycan layer in their cell wall, which is surrounded by an outer membrane containing lipopolysaccharide.
* include many pathogenic species such as Escherichia coli, Salmonella, and Pseudomonas aeruginosa.
* They are often more resistant to antibiotics and can cause a wide range of infections in humans and animals.

colonocytes

* specialized cells found in the lining of the colon (large intestine).
* They play a crucial role in the absorption of water, electrolytes, and nutrients from the digested food passing through the colon.
* have microvilli on their surface, which increase the surface area for absorption.
* They also secrete mucus to protect the colon lining and aid in the movement of fecal matter.
* involved in the production of short-chain fatty acids through the fermentation of dietary fiber by gut bacteria.

polysaccharides

* complex carbohydrates made up of long chains of monosaccharide units.
* commonly found in plants and serve as energy storage molecules or structural components.
* Examples include starch, glycogen, and cellulose.

polypeptide

* a chain of amino acids linked together by peptide bonds.
* It is a primary structure of a protein.

bacteria

* single-celled microorganisms that can be found in various environments, including soil, water, and the human body.
* They are prokaryotic organisms, lacking a nucleus and other membrane-bound organelles.
* While some are harmful and can cause diseases, many others are beneficial and are used in industries like food production and medicine.
* can have different shapes, including spherical (cocci), rod-shaped (bacilli), and spiral (spirilla).
* They reproduce through binary fission, a process where one cell divides into two identical daughter cells.

dietary fibers

* a type of carbohydrate found in plant-based foods that cannot be fully digested by the human body.
* They are classified into two types: soluble and insoluble fibers.
* Soluble fibers dissolve in water and form a gel-like substance, while insoluble fibers do not dissolve in water.

Endocrine signaling systems

* a type of cell communication system in which hormones are released into the bloodstream by endocrine glands.
* These hormones then travel to target cells or organs, where they bind to specific receptors and initiate a response.
* Examples include the pituitary gland, thyroid gland, adrenal glands, and pancreas.

endocrine chemical messengers

* substances produced by endocrine glands that are released into the bloodstream to regulate various physiological processes in the body.
* These messengers, known as hormones, travel through the bloodstream and bind to specific target cells or organs, where they exert their effects.
* Hormones play a crucial role in maintaining homeostasis, regulating growth and development, controlling metabolism, and coordinating reproductive processes.
* Examples include insulin, cortisol, estrogen, and testosterone.

paracrine chemical messengers

* signaling molecules that are released by cells and act on nearby cells.
* They are involved in local communication within tissues and organs.
* Examples include growth factors, cytokines, and prostaglandins.

autocrine chemical messengers

* signaling molecules that act on the same cells that release them.
* They play a role in cell communication and can regulate various cellular processes.
* Examples include growth factors and cytokines.

Na+-glucose transporter

a protein found in cell membranes that facilitates the transport of glucose molecules into cells using the energy from the movement of sodium ions.

It is an important mechanism for glucose uptake in various tissues, including the intestines and kidneys.

Na+-H+ exchanger antiporter

* a membrane protein that facilitates the exchange of sodium ions (Na+) for hydrogen ions (H+) across the cell membrane.
* plays a crucial role in maintaining the pH balance and regulating intracellular sodium levels in various cells and tissues.

Na-Cl cotransporter

* a protein found in the kidneys that helps transport sodium (Na+) and chloride (Cl-) ions across the cell membrane.
* plays a crucial role in the reabsorption of these ions from the urine back into the bloodstream, maintaining electrolyte balance and blood pressure regulation.

GLUT2 facilitative glucose transporter

* a protein that is responsible for transporting glucose across cell membranes.
* It is primarily found in the liver, pancreas, and small intestine.
* has a high capacity for glucose transport and is not dependent on insulin.
* It plays a crucial role in maintaining blood glucose levels and regulating glucose uptake in these organs.

erythrocytes

* red blood cells, are the most common type of blood cell in the human body.
* They are responsible for carrying oxygen from the lungs to the body's tissues and removing carbon dioxide.
* lack a nucleus and other organelles, allowing them to have a biconcave shape and maximize their surface area for efficient gas exchange.
* They are produced in the bone marrow and have a lifespan of about 120 days

fibroblasts

* the most common type of connective tissue cells in the body.
* They are responsible for producing and maintaining the extracellular matrix, which provides structural support to tissues and organs.
* play a crucial role in wound healing, tissue repair, and the formation of scar tissue.
* They also secrete various proteins, such as collagen and elastin, that contribute to the strength and elasticity of tissues.

neurons

* specialized cells that transmit information in the form of electrical signals in the nervous system.
* They are the basic building blocks of the nervous system and are responsible for receiving, processing, and transmitting information throughout the body.
* consist of a cell body, dendrites, and an axon, which allows them to communicate with other neurons through synapses.

hemoglobin

a protein found in red blood cells that is responsible for carrying oxygen from the lungs to the body's tissues and removing carbon dioxide.

It consists of four subunits, each containing a heme group that binds to oxygen.

plays a crucial role in maintaining oxygen balance in the body.

myoglobin

* protein found in muscle tissues that is responsible for storing and transporting oxygen.
* It has a higher affinity for oxygen than hemoglobin, allowing it to efficiently bind and release oxygen in muscle cells.
* plays a crucial role in providing oxygen to working muscles during exercise.

hemocyanin

copper-containing protein found in the blood of some invertebrates, such as mollusks and arthropods.

plays a crucial role in oxygen transport, similar to hemoglobin in vertebrates.

binds to oxygen molecules and carries them throughout the body, giving the blood a blue color

uses copper to bind oxygen

Apoptosis

* a programmed cell death process that occurs in multicellular organisms.
* It is a natural and controlled mechanism by which cells undergo self-destruction.

blood viscosity

* the thickness or stickiness of blood.
* It is a measure of the resistance of blood flow due to the internal friction between blood cells and plasma.
* Factors that affect this include hematocrit (percentage of red blood cells in the blood), plasma proteins, and temperature.

erythropoetin (EPO)

* hormone produced by the kidneys that stimulates the production of red blood cells in the bone marrow.
* plays a crucial role in maintaining the oxygen-carrying capacity of the blood.
* commonly used in medical treatments to treat conditions such as anemia, kidney disease, and certain types of cancer.

glycoprotein hormone

* a type of hormone that consists of a protein chain and a carbohydrate chain.
* These hormones are produced and secreted by various endocrine glands in the body.
* Examples include follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH).
* They play important roles in regulating reproductive processes, growth, and metabolism.

erythroprotein receptor (EPO receptor)

* a protein found on the surface of cells that binds to erythropoietin (EPO).
* When EPO binds to its receptor, it triggers a signaling cascade that promotes the growth and differentiation of red blood cell precursors.
* This process is crucial for maintaining adequate oxygen levels in the body.

Erythrocyte precursor cells (erythroblasts)

* immature cells found in the bone marrow. These cells give rise to red blood cells
* During maturation, they synthesize hemoglobin and gradually lose their nucleus and other organelles.
* The final stage of maturation is the reticulocyte, which is released into the bloodstream and eventually matures into a fully functional erythrocyte

angiogenesis

* the process of forming new blood vessels from pre-existing ones.
* It plays a crucial role in various physiological and pathological processes, such as wound healing, embryonic development, and tumor growth.
* endothelial cells increase and migrate to form new capillaries, which supply oxygen and nutrients to tissues.

recombinant gene product (rHuEPO)

* refers to a protein or molecule that is produced as a result of genetic engineering techniques.
* It is created by combining genetic material from different sources, typically by inserting a specific gene into a host organism's DNA.
* The host organism then produces the product

prokaryotic ribosomes

* cellular structures responsible for protein synthesis in prokaryotic organisms.
* They are smaller in size and consist of two subunits, the 30S and 50S subunits.
* The 30S subunit is involved in decoding the genetic information, while the 50S subunit is responsible for peptide bond formation.
* play a crucial role in the translation of mRNA into proteins.

eukaryotic ribosomes

* cellular structures responsible for protein synthesis in eukaryotic cells. They are larger, more complex, and
* consist of two subunits, the larger 60S subunit and the smaller 40S subunit, which come together during protein synthesis. found in the cytoplasm and on the endoplasmic reticulum (ER) in eukaryotic cells.
* play a crucial role in translating the genetic information encoded in mRNA into functional proteins.

protein translation

* the process by which the genetic information encoded in mRNA is used to synthesize proteins.
* It occurs in the ribosomes, where transfer RNA (tRNA) molecules bring amino acids to the ribosome according to the mRNA sequence.
* The ribosome then catalyzes the formation of peptide bonds between the amino acids, resulting in the synthesis of a polypeptide chain.

process of protein translation

* three main steps: initiation, elongation, and termination.
* Initiation involves the assembly of the ribosome on the mRNA,
* elongation involves the addition of amino acids to the growing polypeptide chain
* termination occurs when a stop codon is reached, leading to the release of the completed protein.

glycosylation

* a post-translational modification process in which a carbohydrate (glycan) is attached to a protein or lipid molecule.
* It plays a crucial role in protein folding, stability, and function.
* can occur in the endoplasmic reticulum and Golgi apparatus, where various enzymes catalyze the addition of specific sugar residues to the target molecule.
* This process is essential for cell-cell recognition, immune response, and many other biological functions.

cytosol

* liquid component of the cytoplasm, which is the gel-like substance inside cells.
* It is a complex mixture of water, ions, small molecules, and proteins.
* plays a crucial role in various cellular processes, such as metabolism, protein synthesis, and signal transduction.
* It provides a medium for biochemical reactions and serves as a storage site for molecules needed by the cell.

endoplasmic reticulum

* a network of membranous tubules and sacs found in eukaryotic cells.
* It plays a crucial role in protein synthesis, lipid metabolism, and calcium storage.
* can be divided into two regions: rough, which is studded with ribosomes and involved in protein synthesis, and smooth, which lacks ribosomes and is involved in lipid metabolism and detoxification.

nucleus

* a membrane-bound organelle found in eukaryotic cells.
* contains the cell's genetic material, including DNA, and is responsible for controlling the cell's activities and reproduction.

plasma membrane

* a thin, flexible barrier that surrounds the cell and separates its internal environment from the external environment.
* It is composed of a phospholipid bilayer with embedded proteins, cholesterol, and other molecules.
* regulates the movement of substances in and out of the cell, allowing for selective permeability.
* It also plays a crucial role in cell signaling and communication.

erythrocyte production

* the process by which red blood cells (erythrocytes) are produced in the body.
* It occurs primarily in the bone marrow, specifically in the spongy tissue called the hematopoietic stem cell niche.
* regulated by the hormone erythropoietin, which is produced by the kidneys in response to low oxygen levels in the blood.
* The process involves the differentiation and maturation of hematopoietic stem cells into erythrocytes, which then enter the bloodstream to carry oxygen to tissues throughout the body.

bone marrow

* a soft, spongy tissue found inside the bones.
* It is responsible for the production of blood cells, including red blood cells, white blood cells, and platelets.
* plays a crucial role in the immune system by producing immune cells.
* It contains two types of bone marrow: red marrow, which is involved in blood cell production, and yellow marrow, which consists mainly of fat cells.

protein kinase

* an enzyme that adds phosphate groups to proteins, a process known as phosphorylation. This modification can regulate the activity, localization, and function of the target protein.
* play crucial roles in various cellular processes, including cell signaling, metabolism, and gene expression.
* involved in numerous physiological and pathological processes, making them important targets for drug development.

tyrosine kinase receptor

* a type of cell surface receptor that is activated by the binding of specific ligands, such as growth factors or hormones.
* have an intracellular domain that possesses kinase activity, which allows them to phosphorylate tyrosine residues on target proteins.
* This phosphorylation event triggers a signaling cascade that regulates various cellular processes, including cell growth, differentiation, and survival.
* Examples include the epidermal growth factor receptor (EGFR) and the insulin receptor.

ligand gated ion channel

* a type of ion channel that opens or closes in response to the binding of a specific molecule, called a ligand, to the channel protein.
* This binding causes a conformational change in the channel, allowing ions to pass through the channel pore.
* play crucial roles in various physiological processes, including neurotransmission, muscle contraction, and sensory perception.
* Examples include nicotinic acetylcholine receptors and GABA receptors.

G-protein coupled receptor

* a type of cell membrane receptor that plays a crucial role in signal transduction.
* It consists of seven transmembrane domains and interacts with a G-protein upon activation.
* involved in various physiological processes, including sensory perception, neurotransmission, and hormone signaling.

cytokines

* small proteins that play a crucial role in cell signaling.
* secreted by various cells in the immune system and act as chemical messengers to regulate immune responses and inflammation.
* can stimulate or inhibit the function of other cells, and they are involved in a wide range of physiological processes, including immune defense, cell growth, and tissue repair.
* Some examples include interleukins, interferons, and tumor necrosis factor.

interferon gamma

* a cytokine, a type of protein, that plays a crucial role in the immune response against viral and bacterial infections.
* It is produced by various immune cells, including T cells and natural killer cells.
* helps activate immune cells, enhances their ability to kill infected cells, and regulates the immune system's inflammatory response.
* It also plays a role in autoimmune diseases and certain cancers.

transmembrane receptor

* a type of protein that spans across the cell membrane, with parts of it located on both the inside and outside of the cell.
* play a crucial role in cell signaling, as they are responsible for transmitting signals from the extracellular environment to the inside of the cell.
* They can bind to specific molecules, such as hormones or neurotransmitters, and initiate a cascade of intracellular events that ultimately lead to a cellular response.
* Examples include G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs).

GTPase activity

* refers to the ability of a protein to hydrolyze GTP (guanosine triphosphate) into GDP (guanosine diphosphate) and inorganic phosphate.
* crucial for various cellular processes, including signal transduction, protein synthesis, and vesicle trafficking.
* involved in regulating key cellular events by switching between an active GTP-bound state and an inactive GDP-bound state.
* Examples include Ras, Rho, and Rab proteins.

pathogenesis

* refers to the process by which a disease develops and progresses within the body.
* It involves the study of the mechanisms and factors that contribute to the initiation, progression, and outcome of a disease.

steps of citric acid cycle

a series of chemical reactions that occur in the mitochondria of cells. Here are the steps of the citric acid cycle:


1. Acetyl-CoA combines with oxaloacetate to form citrate.
2. Citrate is converted to its isomer, isocitrate.
3. Isocitrate undergoes oxidative decarboxylation to form alpha-ketoglutarate, releasing carbon dioxide and reducing NAD+ to NADH.
4. Alpha-ketoglutarate is further decarboxylated to form succinyl-CoA, releasing another molecule of carbon dioxide and reducing NAD+ to NADH.
5. Succinyl-CoA is converted to succinate, generating GTP (which can be used to produce ATP) and reducing FAD to FADH2.
6. Succinate is oxidized to fumarate, reducing FAD to FADH2.
7. Fumarate is hydrated to form malate.
8. Malate is oxidized to oxaloacetate, reducing NAD+ to NADH.

These steps complete one cycle of the citric acid cycle. The cycle can then repeat with the regenerated oxaloacetate to continue producing energy in the form of ATP and reducing agents like NADH and FADH2.

steps of electron transport chain

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1. NADH and FADH2 donate electrons to the first complex, NADH dehydrogenase (Complex I) and succinate dehydrogenase (Complex II) respectively.
2. Electrons are passed from Complex I or Complex II to coenzyme Q (ubiquinone), which acts as a mobile carrier.
3. Coenzyme Q transfers electrons to Complex III (cytochrome bc1 complex), which pumps protons across the inner mitochondrial membrane.
4. Electrons are then transferred from Complex III to cytochrome c, another mobile carrier.
5. Cytochrome c transfers electrons to Complex IV (cytochrome c oxidase), which also pumps protons across the inner mitochondrial membrane.
6. Finally, electrons are transferred from Complex IV to molecular oxygen (O2), forming water (H2O).

Overall, this process generates a proton gradient across the inner mitochondrial membrane, which is used to produce ATP through ATP synthase.

Na+-pumping NADH:quinone oxidoreductase (Na+-NQR) enzyme

* plays a crucial role in the electron transport chain of certain bacteria.
* It is responsible for the transfer of electrons from NADH to quinone, while simultaneously pumping sodium ions across the cell membrane.

steps of glycolysis

The steps of glycolysis are as follows:


1. Glucose phosphorylation: Glucose is converted to glucose-6-phosphate by the enzyme hexokinase.
2. Isomerization: Glucose-6-phosphate is converted to fructose-6-phosphate by the enzyme phosphoglucose isomerase.
3. Phosphorylation: Fructose-6-phosphate is converted to fructose-1,6-bisphosphate by the enzyme phosphofructokinase.
4. Cleavage: Fructose-1,6-bisphosphate is split into two three-carbon molecules, glyceraldehyde-3-phosphate and dihydroxyacetone phosphate.
5. Isomerization: Dihydroxyacetone phosphate is converted to glyceraldehyde-3-phosphate by the enzyme triose phosphate isomerase.
6. Oxidation and phosphorylation: Glyceraldehyde-3-phosphate is converted to 1,3-bisphosphoglycerate, generating NADH and ATP through the actions of glyceraldehyde-3-phosphate dehydrogenase and phosphoglycerate kinase.
7. Substrate-level phosphorylation: 1,3-bisphosphoglycerate is converted to 3-phosphoglycerate, generating ATP through the action of phosphoglycerate kinase.
8. Isomerization: 3-phosphoglycerate is converted to 2-phosphoglycerate by the enzyme phosphoglycerate mutase.
9. Dehydration: 2-phosphoglycerate is converted to phosphoenolpyruvate by the enzyme enolase.
10. Substrate-level phosphorylation: Phosphoenolpyruvate is converted to pyruvate, generating ATP through the action of pyruvate kinase.

These steps occur in the cytoplasm of the cell and are the initial stage of glucose metabolism.

enterocytes

* specialized cells found in the lining of the small intestine.
* They play a crucial role in the absorption of nutrients from the digested food.
* have microvilli on their surface, which increase the surface area for absorption.
* They have transport proteins that facilitate the uptake of nutrients such as glucose, amino acids, and fatty acids.
* secrete digestive enzymes and mucus to aid in the digestion and absorption process.

southern blotting

* a laboratory technique used to detect specific DNA sequences in a sample.
* It involves the separation of DNA fragments by gel electrophoresis, transfer of the fragments to a membrane, and hybridization with a labeled DNA probe.

exergonic \~ equilibrium constant (K)

K > 1

endergonic \~ equilibrium constant (K)

K < 1

@ equilibrium \~ equilibrium constant (K)

K = 1

pancreatic beta cells

* a type of cell found in the pancreas that are responsible for producing and releasing insulin.
* Insulin is a hormone that helps regulate blood sugar levels by allowing cells in the body to take in glucose from the bloodstream.

pancreatic alpha cells

* a type of endocrine cells found in the pancreas.
* They are responsible for producing and secreting the hormone glucagon.
* Glucagon plays a crucial role in regulating blood sugar levels by stimulating the liver to release stored glucose into the bloodstream.

fluid mosaic model

* describes the structure of the cell membrane.
* suggests that the cell membrane is composed of a fluid lipid bilayer with embedded proteins, creating a mosaic-like pattern.
* The lipid bilayer consists of phospholipids that can move laterally within the membrane, giving it a fluid nature.
* The proteins within the membrane can also move and are responsible for various functions such as transport, signaling, and cell adhesion.
* the model helps explain the dynamic nature of the cell membrane and its ability to regulate the movement of substances in and out of the cell.

uncoupling protein (UCP)

* a group of proteins found in the inner mitochondrial membrane.
* play a role in **thermogenesis** by uncoupling the process of ATP synthesis from the electron transport chain.
* leads to the **dissipation of energy as heat**, which can be important for regulating body temperature and energy balance.
* particularly abundant in brown adipose tissue, where they contribute to **non-shivering thermogenesis.**
* heat production due to metabolic energy transformation

oxidative phosphorylation

the process by which cells generate ATP (adenosine triphosphate) through the transfer of electrons from NADH and FADH2 to oxygen.

occurs in the inner mitochondrial membrane and involves a series of protein complexes called the electron transport chain.

As electrons pass through the chain, energy is released and used to pump protons across the membrane, creating an electrochemical gradient.

This gradient drives ATP synthesis by ATP synthase, a protein complex that uses the flow of protons to convert ADP (adenosine diphosphate) to ATP.

Overall, oxidative phosphorylation is a crucial step in cellular respiration, producing the majority of ATP in aerobic organisms.

glucose homeostasis

* refers to the regulation of blood glucose levels within a narrow range in the body.
* It involves the balance between glucose production and glucose utilization.
* insulin and glucagon help maintain stable blood glucose levels, preventing hyperglycemia (high blood sugar) or hypoglycemia (low blood sugar).
* The hormone insulin, produced by the pancreas, plays a crucial role by promoting the uptake of glucose into cells and inhibiting glucose production in the liver.
* Glucagon, another pancreatic hormone, has the opposite effect, stimulating glucose release from the liver.

substrate level phosphorylation

* a metabolic process in which ATP is generated by transferring a phosphate group from a substrate molecule directly to ADP.
* This occurs during glycolysis and the citric acid cycle in cellular respiration.
* It does not involve the electron transport chain and occurs in the cytoplasm or mitochondrial matrix.
* produces a small amount of ATP compared to oxidative phosphorylation.

proton gradient

* a difference in proton concentration across a membrane.
* It is commonly found in biological systems, such as mitochondria and chloroplasts.
* established by the movement of protons across the membrane, either through active transport or facilitated diffusion.
* essential for various cellular processes, including ATP synthesis, ion transport, and signaling.

ATP synthase

* an enzyme found in the inner mitochondrial membrane and chloroplast thylakoid membrane.
* plays a crucial role in cellular respiration and photosynthesis by synthesizing adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and inorganic phosphate (Pi).
* This process is known as oxidative phosphorylation in cellular respiration and photophosphorylation in photosynthesis.
* utilizes the energy stored in the proton gradient across the membrane to drive the synthesis of ATP.
* It consists of two main components: F0, which spans the membrane and acts as a proton channel, and F1, which protrudes into the matrix and contains the catalytic sites for ATP synthesis

Na+-K+ ATPase

* an enzyme that plays a crucial role in maintaining the electrochemical gradient across cell membranes.
* It actively transports sodium ions (Na+) out of the cell and potassium ions (K+) into the cell, against their concentration gradients.
* This process requires the hydrolysis of ATP to provide the energy needed for the ion transport.

transformation

process that transfer genetic material from environment into bacteria.

transduction

process by which nucleic acids are transferred from viruses to cells

contamination

act of making a solution or sample impure