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Search Results for: transition

Transition

Definition noun, plural: transitions (genetics) A small-scale mutation characterized by the replacement of a purine by... Read More

Health transition

Health transition Demographic and epidemiologic changes that have occurred in the last five decades in many developing... Read More

Demographic transition

Definition noun A concept in demography that elucidates the transition from high to low birth and death rates as a country... Read More

Transition mutation

transition mutation A point mutation involving substitution of one base-pair for another, i.e., replacement of one purine... Read More

Valence electron

What are valence electrons? Why are they significant? Valence electrons definition in chemistry: The electrons in an atom's... Read More

Cellular respiration

Cellular Respiration Definition The main function of cellular respiration is to break down glucose to form energy. What is... Read More

Insects

To learn more about arthropods, look at the previous tutorial. The Class Insecta of the Arthropoda Phylum is by far the... Read More

Geological Periods

Precambrian Times (Most Ancient) All time before life existed, Earth was still a volatile environment, though the origins... Read More

Activation energy

Definition noun The amount of energy (in joules) needed to convert all the molecules in one mole of a reacting substance... Read More

Transversion

Definition noun, plural: transversions (genetics) A small-scale mutation characterized by the replacement of a purine by... Read More

Phosphodiester bond

Phosphodiester Bond Definition Phosphodiester bonds are the backbone of the strands of nucleic acid present in the life... Read More

Anaphase

In order to keep the process of biological existence ever-going, the phenomenon of cell multiplication is very important.... Read More

Frameshift mutation

Define Frameshift Mutation What is a frameshift mutation? In biology, insertions or deletions of nucleotides in the coding... Read More

Amphibians & Early Reptiles

Amphibia Definition (Science: zoology) Amphibia is one of the classes of vertebrates. The amphibia are distinguished by... Read More

Phosphorylation

Phosphorylation Definition We can define phosphorylation as a biochemical process in which a phosphate molecule is added to... Read More

Protein

Protein Definition Proteins are biomolecules comprised of amino acid residues joined together by peptide bonds.... Read More

Centrosome

Centrosome Definition What is a centrosome? The centrosome is considered to be the main microtubule-organizing... Read More

Cytokinin

Plants require growth hormones for their regulated growth. Plant growth hormones or regulators (PGRs) are small organic... Read More

Fibroblast

The building block of living things is known as the cell. The cell contributes to many parts and functions of different... Read More

Cytokinesis

The cell cycle of eukaryotes is a cyclical series of biological events that certain asexual cells go through. The cell cycle... Read More

Parthenogenesis

To reproduce, by definition, means to produce new offspring. The process is referred to as reproduction, which is one of the... Read More

Missense mutation

What is a missense mutation? Literally speaking, a mutation that changes the meaning of the encoded gene sequence is the... Read More

Substitution mutation

Definition noun, plural: substitution mutations (genetics) A small-scale mutation characterized by a substitution of one or... Read More

Prophase I

Organisms all use mitosis to create more cells in the body. Meiosis, a similar process, is used in some organisms to undergo... Read More

Cytidine

Definition noun plural: cytidines cy·ti·dine, ˈsaɪtɪdiːn A pyrimidine nucleoside that has cytosine attached to the... Read More

Facultative anaerobe

Facultative Anaerobe Definition What does facultative anaerobe mean? Facultative organisms are the most adaptable... Read More

Living things

Living Things Definition A living thing pertains to any organism or a life form that possesses or shows the characteristics... Read More

Thermophile

Thermophiles Definition What are thermophiles? Let us first understand the literal meaning of the word ‘thermophile’.... Read More

Enzyme

An enzyme is a biomolecule that can be synthesized biologically (naturally occurring) or through other processes... Read More

Depolarization

Depolarization is the removal of polarity by a process or action. It might also be used to describe how such activity leads... Read More

Osteocyte

Osteocyte Definition The osteocyte is a mature bone cell. Other bone cell types are osteoprogenitor cells, osteoblasts, and... Read More

Primitive Animals

Incorrect taxonomic classifications deemed organisms to be either animals or plants, in the Plantae or Animalia kingdoms... Read More

Arthropods

There are over two million species of arthropods, who initially arrived on Earth in the middle of the Cambrian period.... Read More

Mammalian Ancestors

Humans are mammals, the most successful taxonomic class of organisms to colonize the Earth. The word mammal derives from the... Read More

Circulation

Blood Blood is composed of a liquid, plasma, and blood cells such as erythrocytes (red blood cells,) leukocytes (white... Read More

Base pair substitution

Definition noun, plural: base pair substitutions A type of mutation involving replacement or substitution of a single... Read More

At Home in the Universe: The Search for the Laws of Self-Organization and Complexity

At Home in the Universe: The Search for the Laws of Self-Organization and Complexity  ... Read More

Angiosperm

Angiosperms Definition What is an angiosperm? An angiosperm is a plant that produces flowers. The angiosperms, also... Read More

Activation

Definition noun (general) The state or the process of being active and/or effective (biochemistry) The process of making a... Read More

Ecosystem

Ecosystem Definition An ecosystem is a system consisting of biotic and abiotic components that function together as a unit.... Read More