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152 recordsThe Cell · The cell
The smallest unit that can carry out the processes of life.
Plasma Membrane · Plasma membrane
A selective boundary that separates a cell from its surroundings.
Nucleus
The membrane-bound compartment that contains most eukaryotic DNA.
Mitochondrion
An organelle that supports energy conversion and many other cellular processes.
Neuron
An excitable cell specialized to receive, integrate, and transmit information through electrical and chemical signaling.
Homo sapiens · Human
The human species, used here as the organism context for the curated TP53 and p53 records.
Adipocyte
Adipocytes store or use energy and send signals that help coordinate whole-body metabolism.
Allele
One of the alternative DNA sequence forms found at a particular genetic locus.
Amino Acids · Protein-building amino-acid set
Meet the 20 standard amino acids that build most proteins, plus selenocysteine and pyrrolysine, two rare amino acids that some organisms encode directly.
Antibiotic
A medicine that kills or inhibits susceptible bacteria; antibiotics do not treat viral infections.
Antigen
A molecular structure that can be specifically recognized by immune receptors or antibodies.
Archaea
A domain of cellular life distinct from Bacteria and Eukarya, with diverse metabolisms and habitats.
Astrocyte
Astrocytes help maintain the chemical environment around neurons and interact with blood vessels and synapses.
B Cell · B cell
A lymphocyte whose activated descendants can secrete antibodies and form memory cells.
Bacteria
One of the three domains of cellular life, comprising prokaryotic organisms with extensive metabolic and ecological diversity.
Basophil
Basophils are rare circulating granulocytes that can participate in allergic and type 2 immune responses.
Biased Agonism · Biased agonism
A ligand-dependent preference for some receptor signaling routes over others.
Biogeochemical Cycles · Biogeochemical cycles
Transfers and transformations of elements among organisms and environmental reservoirs.
Blood Cell
Blood cells develop from hematopoietic stem cells and include cells that transport gases, defend against infection, or support clotting.
Cardiac Muscle Cell
Cardiac muscle cells contract in a coordinated way to pump blood through the heart.
Cell Signaling · Cell signaling
How cells detect information and convert it into changes in behavior, chemistry, or gene activity.
Cell Wall · Cell wall
A supportive outer layer found in plants, fungi, and many microorganisms; animal cells do not have cell walls.
Chloroplast
A plant and algal organelle that houses photosynthetic membranes and carbon-assimilation machinery.
Chloroplast Stroma · Chloroplast stroma
The aqueous compartment inside the chloroplast envelope and outside the thylakoid lumen.
Cholangiocyte
Cholangiocytes line bile ducts and modify the fluid that flows through them.
Chondrocyte
Chondrocytes make and maintain the specialized matrix of cartilage.
Concentration Gradients · Concentration gradients
Differences in a molecule's concentration across space that can drive diffusion and help power transport.
Connective Tissue Cell
Connective-tissue cells help make, maintain, or remodel the matrix that supports tissues.
CRISPR Gene editing · CRISPR gene editing
A programmable system adapted from microbial defense to target selected DNA sequences.
Cyanobacteria
A group of bacteria that perform oxygenic photosynthesis and contribute to aquatic and terrestrial primary production.
Cytoplasm
The contents of a cell outside the nucleus, including cytosol and many cellular structures.
Cytoskeleton
A network of protein filaments that supports cell shape, movement, organization, and intracellular transport.
Cytosol
The aqueous phase of the cytoplasm outside membrane-enclosed organelles.
Cytotoxic T cell
A CD8⁺ T lymphocyte that can kill target cells displaying recognized peptide–MHC class I complexes.
Dendritic Cell
Dendritic cells collect and process material, then can show antigen fragments to T cells.
DNA Base pair · DNA base pair
Two complementary DNA bases joined across opposite strands: adenine pairs with thymine, and cytosine with guanine.
DNA-encoded Libraries · DNA-encoded libraries
Collections of small molecules tagged with DNA barcodes that record each compound's identity during pooled binding selections.
Drug Selectivity · Drug selectivity
How preferentially a drug affects one target or pathway compared with other biological targets.
Electron Carriers · Electron carriers
Small molecules such as NADH that collect and deliver electrons between metabolic reactions.
Endocrine Cell
Endocrine cells release hormones or other signals that can coordinate activities in distant cells and organs.
Endoplasmic Reticulum · Endoplasmic reticulum
A membrane network involved in protein production and processing, lipid synthesis, and calcium storage.
Endosome
A membrane-bound sorting compartment that receives endocytosed cargo and routes it for recycling, further transport, or degradation.
Endothelial Cell
Endothelial cells form the inner lining of blood and lymphatic vessels.
Enterocyte
Enterocytes absorb nutrients from the inside of the intestine.
Enteroendocrine Cell
Enteroendocrine cells sense nutrients and other cues and release hormones that help coordinate digestion and metabolism.
Enzymes
Biological catalysts that speed reactions; most known enzymes are proteins, while some RNA molecules also catalyze reactions.
Eosinophil
Eosinophils are granulocytes involved in responses to some parasites and in allergic inflammation.
Ependymal Cell
Ependymal cells line fluid-filled spaces in the brain and spinal cord.
Epidemiology
Study of how health events are distributed in populations and what factors influence them.
Epithelial Cell
Epithelial cells form sheets that cover surfaces and line many organs and tubes in the body.
Epstein-Barr virus · Human gammaherpesvirus 4
A very common herpesvirus that spreads mainly through saliva and stays in the body for life after infection.
Erythrocyte
An erythrocyte, or red blood cell, carries oxygen through the blood using hemoglobin.
Escherichia coli
A diverse bacterial species that includes harmless strains as well as strains associated with disease.
Fed And fasting states · Fed and fasting states
Coordinated changes in hormones and fuel use that help the body respond to eating and time without food.
Fibroblast
Fibroblasts make and remodel much of the extracellular matrix that supports tissues.
Gene
A region of genetic material used to produce a functional RNA; some genes also provide instructions for a protein.
Gene Variants · Gene variants
DNA sequence differences that can have many different effects.
Genetic Variation · Genetic variation
Differences in genetic material among individuals or populations, generated and reshaped by multiple processes.
Genomics
Study of an organism's genome, including its sequence, organization, variation, and change over time.
Genotype
The genetic-variant or allele combination considered for an individual or locus.
Germ Cell
Germ cells give rise to gametes and pass genetic information to the next generation.
Glial Cell
Glial cells are nervous-system cells that support, protect, insulate, or regulate the environment around neurons.
Goblet Cell
Goblet cells secrete mucus that helps protect and lubricate epithelial surfaces.
Golgi Apparatus · Golgi apparatus
A membrane-bound sorting and processing center that receives cargo from the ER and sends it to destinations.
GPCR Agonists and antagonists · GPCR agonists and antagonists
Ligands that increase or prevent a G-protein-coupled receptor's signaling response.
Granulocyte
Granulocytes are white blood cells with prominent cytoplasmic granules, including neutrophils, eosinophils, and basophils.
GTPase-activating Proteins · GTPase-activating proteins
Proteins that accelerate GTP hydrolysis by a GTPase, helping return the switch toward its GDP-bound state.
Guanine Nucleotide dissociation inhibitors · Guanine nucleotide dissociation inhibitors
Regulators that bind GDP-bound members of selected small GTPase families and can influence their activity and localization.
Guanine Nucleotide exchange factors · Guanine nucleotide exchange factors
Proteins that help a GTPase release GDP so GTP can bind and activate the switch.
Helicobacter pylori
A Gram-negative bacterium that colonizes the stomach lining and is a major cause of peptic ulcers.
Helper T cell
A CD4⁺ T lymphocyte that coordinates immune responses through cell contacts and secreted signals.
Hepatitis B virus
A partially double-stranded DNA virus that infects liver cells and causes hepatitis B.
Hepatitis C virus · Orthohepacivirus hominis (hepatitis C virus)
A positive-sense RNA virus that infects the liver and causes hepatitis C.
Hepatocyte
Hepatocytes are the main working cells of the liver and carry out many chemical tasks for the body.
High-throughput Screening · High-throughput screening
Automated testing of many candidate molecules in parallel to find compounds with a desired measurable activity.
How Kinase inhibitors work · How kinase inhibitors work
Kinase inhibitors can bind different structural states or sites and interfere with phosphorylation signaling.
Human immunodeficiency virus 1 · HIV-1
A retrovirus that infects immune cells and causes HIV infection; HIV-1 accounts for most infections worldwide.
Human immunodeficiency virus 2 · HIV-2
A retrovirus distinct from HIV-1 that also causes HIV infection; laboratory HIV testing looks for antibodies to both HIV-1 and HIV-2.
Keratinocyte
Keratinocytes make up most of the epidermis and help form a protective barrier.
Ketone Bodies · Ketone bodies
Small molecules made mainly by the liver from acetyl-CoA and used as fuel by several tissues during prolonged fasting.
Leukocyte
Leukocyte is the broad name for a white blood cell, a member of the body's immune and defense systems.
Leydig Cell
Leydig cells produce testosterone in response to hormonal signals.
Ligands And receptors · Ligands and receptors
A ligand is a molecule that binds a specific partner, such as a receptor, and can change its activity.
Lymphocyte
A lymphocyte is an immune cell family that includes B cells, T cells, and natural killer cells.
Lysosomal Storage disorders · Lysosomal storage disorders
Inherited conditions in which lysosomal enzyme or transporter defects disrupt breakdown and recycling of cellular material.
Lysosome
An acidic compartment where enzymes digest selected cellular material for recycling and other functions.
Macrophage
Macrophages are tissue immune cells that engulf material and help coordinate defense, cleanup, and repair.
Major Human Cell Types · Representative human cell-type atlas
Explore representative cell types across blood, immunity, organs, metabolism, the nervous system, and reproduction. This is a guided starting set, not an exhaustive inventory of every human cell state.
Mast Cell
Mast cells are tissue-resident immune cells that can rapidly release stored mediators during certain immune reactions.
Megakaryocyte
Megakaryocytes are large bone-marrow cells that produce platelets.
Melanocyte
Melanocytes make melanin pigment and transfer pigment-containing structures to nearby cells.
Membrane Potential · Membrane potential
A voltage difference across a cell membrane created by unequal ion distributions and selective permeability.
Memory B Cell
Memory B cells can persist after an immune response and respond more quickly if a related antigen appears again.
Microglial Cell
Microglia are resident immune cells that monitor and respond to changes in the central nervous system.
Molecular Glues · Molecular glues
Small molecules that stabilize or create an interaction between proteins, changing the function or fate of one or both partners.
Monocyte
Monocytes circulate in blood and can take part in defense and tissue repair.
Muscle Cell
Muscle cells generate force using actin and myosin, but their structure and control differ across tissues.
Mycobacterium tuberculosis
The bacterium that causes tuberculosis, spread through the air when a person with TB disease of the lungs or throat coughs or speaks.
Natural Killer Cell
Natural killer cells are lymphocytes that can respond to some infected or abnormal cells without first learning a unique antigen through a T-cell receptor.
Neutrophil
Neutrophils are fast-responding white blood cells that help control many bacterial and fungal infections.
Noncoding RNA
RNA molecules that perform functions without serving as templates for protein synthesis.
North American deer mouse
Peromyscus maniculatus, a rodent that serves as an important reservoir host for Sin Nombre virus in the United States.
Nucleolus
A dynamic region inside the nucleus where ribosomal RNA is made and ribosome subunits begin to assemble.
Nucleotide
A building block of DNA or RNA made of a sugar, a phosphate group, and a nitrogen-containing base.
Oligodendrocyte
Oligodendrocytes make myelin around parts of axons in the central nervous system.
Oocyte
An oocyte is a female germ cell that has entered meiosis and can contribute a haploid genome to an embryo after fertilization.
Orthoebolavirus zairense
A species of filovirus that includes viruses responsible for Ebola disease outbreaks.
Orthohantavirus sinnombreense
A hantavirus species whose reservoir in the United States is chiefly the deer mouse and that can cause hantavirus pulmonary syndrome.
Osteoblast
Osteoblasts build new bone matrix and help control its mineralization.
Osteoclast
Osteoclasts break down bone matrix as part of normal bone remodeling.
Osteocyte
Osteocytes are mature bone cells embedded in the matrix they help maintain.
Oxygen Gradient · Oxygen gradient
A spatial difference in oxygen availability that can support different microbial metabolisms in one environment.
Pancreatic Alpha Cell
Pancreatic alpha cells release glucagon, a hormone that helps coordinate fuel availability, especially during fasting.
Pancreatic Beta Cell
Pancreatic beta cells release insulin when blood glucose and other signals indicate that fuel is available.
Paneth Cell
Paneth cells release antimicrobial molecules near the base of small-intestinal crypts.
Pathogen
A biological agent that can cause disease in a host under particular conditions.
Pedigree Analysis · Pedigree analysis
Use of family relationships and trait observations to evaluate possible inheritance patterns.
Pericyte
Pericytes sit alongside endothelial cells on many small blood vessels.
Peroxisome
An organelle that carries out specialized oxidative reactions, including selected steps in lipid metabolism.
Phage Display · Phage display
A selection method that links a displayed peptide or antibody fragment to the genetic sequence that encodes it.
Phenotype
An observable or measurable characteristic shaped by genetic, developmental, and environmental factors.
Photoreceptor Cell
Photoreceptor cells convert light into changes in electrical signaling in the retina.
Plasma Cell
Plasma cells are antibody-secreting cells that develop from activated B cells.
Plasmodium falciparum
A protozoan parasite and a major cause of severe malaria in humans.
Podocyte
Podocytes wrap around kidney glomerular capillaries and help form the filtration barrier.
Potency And efficacy · Potency and efficacy
Two different properties: how much drug is needed for an effect and how large an effect the drug can produce.
Protein Binding pockets · Protein binding pockets
Regions of a protein surface or interior that can accommodate a molecule and support binding.
Protein Druggability · Protein druggability
How well a protein can be reached and modulated by a medicine with useful selectivity and effect.
Protein Kinases · Protein kinases
Enzymes that transfer phosphate groups, usually from ATP, onto protein targets.
Protein Phosphatases · Protein phosphatases
Enzymes that remove phosphate groups from proteins and help balance kinase activity.
Proton-motive Force · Proton-motive force
Stored electrochemical energy created by differences in proton concentration and charge across a membrane.
Proximal Tubule Epithelial Cell
Proximal tubule cells reclaim much of the filtered water and useful solutes from kidney fluid.
Punnett Square · Punnett square
A grid for enumerating possible allele combinations from specified parental gametes.
Regulatory T Cell
Regulatory T cells help limit immune responses and support immune tolerance.
Resistance To kinase inhibitors · Resistance to kinase inhibitors
Tumor cells can restore signaling or alter drug binding so a kinase inhibitor loses effect.
Retinal Cone Cell
Cone cells support color vision and detailed vision in brighter light.
Retinal Rod Cell
Rod cells are retinal photoreceptors that are highly sensitive to dim light.
Schwann Cell
Schwann cells support peripheral nerves and can wrap axons with myelin.
Second Messengers · Second messengers
Small intracellular signals that relay and distribute information after many receptors are activated.
Sertoli Cell
Sertoli cells support developing sperm cells inside the seminiferous tubules.
Skeletal Muscle Cell
Skeletal muscle cells generate force for movement and posture and can respond to voluntary motor commands.
Smooth Muscle Cell
Smooth muscle cells change the diameter of vessels and move or regulate material through hollow organs.
Sperm Cell
A sperm cell is a mature male gamete that can deliver a haploid genome to an egg during fertilization.
T Cell
T cells are lymphocytes whose receptors recognize specific molecular fragments displayed by other cells.
Target Engagement · Target engagement
Evidence that a candidate medicine binds or otherwise interacts with its intended biological target in a relevant setting.
The Genetic code · The genetic code
Rules that relate three-base RNA codons to amino acids or translation stop signals.
Thylakoid
An internal chloroplast membrane sac that carries photosystems, electron-transfer complexes, and ATP synthase.
Transport Vesicle · Transport vesicle
A small membrane-bound carrier that moves selected cargo between cellular compartments or to the cell surface.
Treponema pallidum
The spirochete bacterium species that includes the subspecies causing syphilis.
Type I Alveolar Cell
Type I alveolar cells form much of the thin surface across which oxygen and carbon dioxide exchange.
Type II Alveolar Cell
Type II alveolar cells make pulmonary surfactant, which helps keep alveoli from collapsing during breathing.
Virus
An acellular infectious agent whose replication depends on host-cell machinery.