Science Word Starting With U: A list of science words starting with the letter ‘U’

Do you like learning new science words? I've made a list of some interesting science words that start with U to help you.

Science words that start with U is a list of all the cool and interesting science words starting with the letter u. There are many science words beginning with u and they can be very silly and funny.

Science is filled with interesting words that start with the letter U. From Unabomber to Umbrella Vector, this science dictionary presents the most common scientific words starting with U.

Science word start with u

Science Glossary of Words Starts With Letter ‘U’

Ultraviolet Radiation: Electromagnetic radiations are of different types with different wavelengths. Among those, ultraviolet radiation is one part and exists within the range of wavelength 10nm to 400 nm. Based on wavelength range, ultraviolet radiation lies shorter to visible rays and longer to X-rays. In regards to frequency, it ranges between 30 PHz to 750 THz. Sun is the main source of ultraviolet radiation, constituting 10% of total electromagnetic radiation.

Coming to human health, the UV rays from the sun are not good for health and cause many kinds of cancer. Of Course, it is natural but overexposure to it may put you in several medical conditions.

Unimolecular Reaction: Any type of reaction which involves only one molecule as a reacting substance refers to a unimolecular reaction. The single reactant molecule rearranges itself to form at least one or more than one product. The best common example of unimolecular reactions is radioactive decay reactions, where an atom rearranges itself and emits particles. Racemization, cis-trans isomerization, and ring-opening process in a chemical reaction also come under unimolecular reactions.

Ultra-High Frequency: The radio frequencies ranging between 300 megahertz (MHz) and 3 gigahertz (GHz) denotes ultra-high frequency. These frequencies are highly useful for manufacturing cell phones, satellite communication, and television broadcasting. In short form, UHF denotes ultra-high frequency. Forex: We can find these high frequencies in personal radio services, Bluetooth, and Wi-Fi mechanisms.

Ultra-Low Frequency: Ultra-low frequencies are frequencies that range between 300 and 3000 Hz of the electromagnetic spectrum. And in short and abbreviated form, denoted as ULF. Mainly, these low frequencies are useful for communicating with submarines. According to earlier researches on these low frequencies tell that they are harmful to human health on long exposure. 

UN ID: UN ID is the harm identifier number value useful for determining hazardous and flammable chemicals. This number comes in four-digit, ranging from UN0001 to about UN3500. And assigned by the United Nations Committee of Experts on the Transport of Dangerous Goods. The other alternate names for UN ID are United Nations number and UN Identifier. Forex: UN2074 is the UN number of acrylamide. 

Unit: In a chemical laboratory, a unit is a standardized unit useful for denoting the measurements of liquid substances. Forex: Metre is the standard unit for measuring lengths and liter is the standard unit that represents volume. 

Universal Gas Constant: Universal gas constant, otherwise known as ideal gas constant, and molar gas constant is a standardized physical gas constant. The letter ‘R’ symbolizes the universal gas constant and is almost equivalent to Boltzmann’s Constant. The value of R is 8.3144621(75) J/K·mol and we can see gas constant in ideal gas law i.e. PV= nRT; Where R= Universal Gas Constant

Unit Cell: In crystallography, the smallest and repeating unit of cubic structure is the unit cell. It is the main building unit of a crystal lattice structure.

Universal Indicator: Universal indicator is a factor that determines the pH values of the solutions made of many compounds. It tells the color changes happening in the solution in the form of pH values ranging between 0-14 and determines whether the solution is an acid or base. Here are the common pH indicators that work as standard: Red= 0 ≥ pH ≥ 3; Yellow= 3 ≥ pH ≥ 6; Green 7; Blue= 8 ≥ pH ≥ 11; Purple= 11 ≥ pH ≥ 14.

Unpaired Electron: In chemistry, the electron which stays single and occupies the atomic orbital solely instead of pairing with other electrons is the unpaired electron. In general, any type of atomic orbital can host two electrons moving in opposite spins. 

Universal Solvent: The liquid or liquid solution, which can dissolve almost all the substances in it rather than any other liquids is the universal solvent. Water is the best common example of universal solvent since water dissolves more substances when compared to other liquid substances. Because it has a polar bonding arrangement of hydrogen and oxygen atoms which has a positive charge on one side and a negative charge on the other side. 

Unsaturated: In chemistry, the term unsaturated denotes too many definitions such as:

1) Any chemical compound which contains double or triple bonds between the carbon atoms refers to an unsaturated compound.

2) The type of solution which can absorb or dissolve any type of other added substances is nothing but unsaturated. 

3) The chemical compounds that tend to undergo additional reactions to produce one or more products denote unsaturated compounds. Forex: Alkenes and Alkynes

Unsaturated Solution: The chemical solution referred to as unsaturated solution when the concentration of solute is lower than the saturation value of solvent is the unsaturated solution. To put it simply, when you put solute into the solvent solution, all the amount of solute gets dissolved and is ready to dissolve more amount as well. 

Unsaturated Fat: The beneficial type of fats that stay in liquid form at room temperature, encompassed of more than two carbon double bonds in unsaturated fat. We can get natural unsaturated fats from plants such as myristoleic acid, palmitoleic acid, arachidonic acid, and linoleic acid. And the foods that contain unsaturated fats include avocado, olive oil, nuts, etc. 

Ununhexium: Ununhexiumis the substituent name for a chemical element that is synthetic holding the atomic number 116 i.e. Livermorium. Since it is man-made, it is available in lesser amounts and hence only useful in the research fields. The chemical symbol for Ununhexium is Uuh. 

Ununoctium: Ununoctium is the earlier name for super heavy chemical element i.e. Oganesson. It has the atomic number 118 and symbol ‘Uuo’ for the earlier name and ‘Og’ for the current one. It is not a natural chemical element and was artificially prepared for the first time in 2002 at Joint Institute for Nuclear Research in Dubna. 

Ununquadium: Ununquadiumis the term given to the chemical element in earlier days, which is currently popular with the name, Flerovium. The atomic number of Flerovium is 114 and by nature, this element is synthetic and highly radioactive. Uuq was the earlier symbol of Ununquadium and FI is the current symbol.

Ununpentium: Ununpentium was the earlier name and is currently popular with the chemical name ‘Moscovium’. It is a man-made chemical element with an atomic number 115 and was synthesized for the first time in the year 2003. This metal element is the resulting product of the chemical reaction between atoms of the element Americium-243 and the ions of calcium-48. By nature, it is a highly reactive radioactive element with the symbol ‘Uup’ for the earlier name and ‘Mc’ for the current name.

Ununseptium: The highly reactive synthetic chemical element with atomic number 117 and symbol Ts, Tennessine was popular with the name in earlier days as Ununseptium.Since it is an artificial element, it is available in every minute quantities but is well-known as the second heaviest element. It holds last to second place in the 7th period of the periodic table.

Uranium: Uranium is the term given to the chemical element of the periodic table which takes atomic number 92 and the symbol ‘U’. Uranium is a radioactive element but exposure to it may not cause hazardous health issues. Because human skin is resistant to alpha particles emitted by uranium elements. But of course, it is still dangerous to handle uranium because it may cause bone or liver cancer under certain conditions.  

Ununtrium: Ununtrium is the old name for the chemical element Nihonium. It is also a synthetic chemical element that takes up 113 atomic numbers and the symbol Nh. Nihonium-286 is the most stable isotope of this highly reactive radioactive element. Nihonium belongs to group 13 and period 7 in the periodic element.

Science Glossary of Words related to Biology and Astronomy

Unearth: Unearth is the term useful for something found in the ground by digging.

Universal: Universal is related to the people or things doing things together in the world. Anything related to the world and its objects is universal.

Unpredictable: The term unpredictable is useful for conditions that cannot be detected certainly. Forex: Unpredictable conditions

Unusual: In chemistry and biology, the word unusual refers to something that is not common or habitually done.

Ursine: Anything that is belonging to the bears is ursine.

Coenzyme Q10: Coenzyme Q10 is a naturally producing nutrient supplement in the human body. It works effectively as an anti-oxidant plus plays a major role in the functioning of the respiratory system. We also find coenzyme Q10 in many types of food and provide energy to all the body cells. Regulating blood sugar levels, recovers heart health, treating cancer, and controls migraine frequencies are the other functions of coenzyme Q10.

Ubiquitin: Ubiquitin is a small and regulatory protein that exists inside the muscles of all eukaryotic cells. It implements its functions by associating with a wide range of target proteins. It works effectively in the synthesis of new proteins and the destruction of any defective proteins. And it consists of 76 amino acids with a molecular mass of 8.6 kDa. 

Ubiquitin-Proteasome System: Ubiquitin-Proteasome System, shortly termed as UPS is a significant cellular quality control system that helps in the degradation of proteins in the tissues of eukaryotic cells. 

Under Dominance: Under dominance is opposite to overdominance which refers to the natural selection of phenotypic expression of the heterozygote. Either of the wild type and mutant homozygotes is also associated during under dominance. 

Unequal Crossing Over Unequal crossing over is a type of gene transfer either through duplication and deletion methods. It works by deleting some part of the actual DNA sequence and substituting it with duplicated genes. These duplicated genes may get separated either from the homologous chromosome of meiosis or the sister chromatid of mitosis. They are capable of interchanging DNA sequences of different chromosomes. 

Unequal Crossover: Unequal crossover is the cross-over between imperfectly arranged homologs. It is almost similar to unequal crossing over. 

Unicellular: Unicellular organism consists of only a single cell, unlike multicellular organisms. They are also popular as single-celled organisms. These single-celled organisms are classified into two main categories of organisms such as eukaryotic organisms and prokaryotic organisms. Forex: Protozoa, Escherichia coli, Streptococcus, Protista, Dinoflagellates, and Pneumococci. 

Unfavorable Reaction: In chemical thermodynamics, an unfavourable reaction is nothing but an endergonic reaction, where the emitted energy change exhibits positive. And these reactions need extra force to drive the reaction to further steps. Such a driving force helps in reducing the activation energy and thus drives the reaction to further steps. Also, in such reactions, the energy state of reactants is lesser than the energy state of products. 

 Uninemic Chromosome: Uninemic chromosome is a linear arrangement of gene sequences present in the form of the double helix of DNA. These chromosomes are seen in the nucleus of cells bounded with proteins. 

Uniparental Inheritance: The type of inheritance transmitted by organelle genes such as mitochondria and chloroplast of definite phenotypes from one parent to all progeny is uniparental inheritance. 

Unique DNA: Any type of DNA sequence that does not consist of any repetitive sequences refers to unique DNA. Mostly, structural genes and introns belonging to them come under unique DNA sequences. 

Unique Mutation: The type of mutation which exists and happens only once is a unique mutation. Forex: Mutation in vitamin D receptor gene

Unmixed Codon Family: A collection of four codons code for the same amino acid by sharing their primary two bases that come under the unmixed codon family. 

Unsaturated Hydrocarbon: Any chemical compound consisting of carbon atoms bonded through double or triple bonds is an unsaturated hydrocarbon. Unsaturated hydrocarbons are ready to captivate additional hydrogen atoms. 

Unstable Mutation: In genetics, the type of mutation is reversible and is dynamic with high frequency. It works by regulating the introduction of the heritable controlling element, which is responsible for reversion. 

UTR: The full form of UTR is an untranslated region, which refers to the coding sequences on mRNA present on either side of it. There are two main types of UTR on mRNA i.e. 3’ UTR and 5’ UTR. 

Upstream: Upstream in genetics and molecular biology states the relative position of gene sequences on double-stranded DNA i.e. at 5’ end of DNA strand. 

Uracil: RNA is a composition of four types of chemical bases. Uracil is one of those chemical bases. This base substitutes by thymine while forming DNA.

Unusual Bases: Unusual bases are the bases formed after the transcription process of regular bases. 

URF: URF is an open reading frame whose functionality is not yet known. The full form of URF is the Unassigned Reading Frame. 

Uridine: Uridine is a significant nucleoside that consists of uridine as the base. It helps in treating life-threatening medical conditions caused due to overdose or intake of capecitabine or fluorouracil compounds. Such life-threatening side effects may connect to the heart, stomach, intestines, nervous system, and blood cells. 

Udometer: The medical instrument that is useful for measuring rainfall i.e. it measures the quantity of liquid precipitation in an area in a predefined period is the udometer. 

Urethroscope: Urethroscope is a laboratory device useful for examining the internal part of the urethra doe detecting any defects. And the process of examining the inside part of the bladder and urethra is urethroscopy. 

Ultra-microscope: An optical device that consists of a microscope to detect tiny particles by illuminating light at lower wavelengths at certain angles is nothing but an ultra-microscope. Mainly, this instrument is useful for observing the Tyndall effect on a dark background. 

Urinometer: Urinometer is a specific laboratory device designed for determining the specific gravity of urine and also helps in measuring the concentrating power of the kidney. 

Science words Starts with Letter u

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This worksheet includes a list of words that start with the letter U. Students can copy or type out the words and add them to a word search puzzle. The next step is for students to research the meanings of the words.

Worksheet for Science words starts with u

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