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Browse Qlopedia topics grouped under Science.
298 topics, showing 217-240 on page 10 of 13.
PCR, or polymerase chain reaction, is a laboratory technique for rapidly amplifying a selected DNA segment. By cycling temperature and using primers plus a heat-stable DNA polymerase, PCR can turn tiny amounts of genetic material into enough copies for analysis.
DNA polymerases are enzymes that build DNA strands from nucleotide building blocks. They are essential for genome replication, many DNA repair pathways, and laboratory techniques that copy DNA, but they can only extend from a primer and synthesize new DNA in one direction.
RNA polymerase is the enzyme that synthesizes RNA from a DNA template during transcription. It recognizes transcription start regions with help from other factors, opens DNA locally, adds RNA nucleotides, and produces transcripts used as mRNA, rRNA, tRNA, and other RNAs.
Translation is the biological process that uses messenger RNA instructions to build a protein. Ribosomes read mRNA codons, transfer RNAs bring amino acids, and the growing chain folds into a protein that can do cellular work.
Transcription is the process of making an RNA copy from a DNA template. It is a central step in gene expression, allowing cells to turn stored DNA information into messenger RNA, ribosomal RNA, transfer RNA, and other functional RNA molecules.
A ribosome is a cellular machine made of ribosomal RNA and proteins that builds proteins from messenger RNA instructions. It reads codons, positions transfer RNAs, forms peptide bonds, and links the genetic code to the working proteins of the cell.
The genetic code is the rule set cells use to translate nucleotide sequences into protein sequences. It connects codons in messenger RNA with amino acids, start signals, stop signals, and the molecular machinery that builds proteins.
A mutation is a change in genetic sequence. Mutations can happen during DNA copying, after DNA damage, or through larger chromosome changes, and they can be neutral, harmful, beneficial, inherited, or limited to particular cells.
An allele is one version of a DNA sequence at a particular genomic location. Alleles explain why individuals can carry different versions of the same gene or DNA segment, and they help connect inheritance, traits, genetic variation, and disease risk.
A gene is a stretch of genetic sequence that helps produce a functional product, usually a protein or a functional RNA molecule. Genes are carried in genomes, inherited through reproduction, regulated by cells, and changed by mutation and variation.
A genome is the complete set of genetic material in an organism, cell, organelle, or virus. In cellular life it is usually DNA, organized into chromosomes or other structures, and it includes genes, regulatory sequences, repeated DNA, and other regions that shape inheritance, development, and evolution.
A chromosome is a packaged DNA molecule, together with proteins, that helps cells organize, copy, read, and pass on genetic information. Chromosomes make long DNA usable inside cells and help ensure that inherited instructions are distributed during cell division.
DNA, or deoxyribonucleic acid, is the molecule that stores hereditary instructions in cells and many viruses. Its double-helix structure, base pairing, and organization into genes and chromosomes let organisms copy information, pass it on, and use it to build proteins.
RNA, or ribonucleic acid, is a nucleic acid that helps cells copy, use, regulate, and sometimes store genetic information. RNA molecules can carry protein instructions, form part of ribosomes, deliver amino acids, regulate genes, catalyze reactions, and serve as genetic material in some viruses.
Amino acids are small organic molecules with an amino group, a carboxyl group, and a variable side chain. Cells join them into peptides and proteins, and their side chains help determine protein shape, chemistry, nutrition, and many metabolic roles.
Proteins are large biological molecules made from amino acid chains. Their sequences fold into shapes that let cells build structures, catalyze reactions, carry signals, move materials, defend against disease, and turn genetic instructions into working biology.
Enzymes are biological catalysts that let cells run chemistry fast enough for life. Most are proteins, a few are catalytic RNA, and their folded shapes help them bind specific substrates, lower activation energy, and release products without being used up.
Yeasts are single-celled fungi that live in soil, on plants, on fruit, in fermented foods, and in many human-made processes. Some yeasts turn sugars into carbon dioxide and alcohol, which makes them useful in bread, beer, wine, biotechnology, and research, while other yeasts live quietly in ecosystems or occasionally cause disease.
A heat wave is a period of unusually hot weather that lasts long enough to strain bodies, buildings, power systems, roads, farms, and ecosystems. The danger depends on local climate, humidity, nighttime temperatures, exposure, health, housing, and access to cooling, which is why the same temperature can be routine in one place and hazardous in another.
A heat-transfer process that lets surfaces lose thermal energy by emitting infrared radiation, sometimes cooling buildings, materials, or landscapes without active refrigeration.
Lithium is the lightest metal and a highly reactive alkali element. It is central to lithium-ion batteries, but it also appears in ceramics, glass, lubricants, medicines, alloys, and emerging geothermal-brine supply chains.
Rare-earth elements are a group of chemically similar metals used in magnets, lights, catalysts, electronics, defense systems, and clean-energy technologies. They are not all geologically rare, but they are difficult to separate and refine.
A radio telescope is an astronomical instrument that collects radio waves from space, turning faint signals from planets, gas clouds, stars, galaxies, pulsars, and black-hole environments into data scientists can analyze.
Fermentation is a biochemical process in which cells and microorganisms break down sugars without oxygen, producing energy and compounds such as acids, alcohol, and carbon dioxide.