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Proboscis

/prəˈbäsəs/ Noun, pl. proboscises 1. An elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular mouthparts used for feeding and sucking. In vertebrates, the term is used to describe an elongated nose or snout. (wikipedia.org) 2. The nose of a mammal, esp. when it is long and mobile, such as the trunk of an elephant (Google Dictionary); the human nose especially when prominent (merriam-webster.com). 4. Any of various elongated or extensible tubular processes (as the sucking organ of a butterfly) of the oral region of an invertebrate. (merriam-webster.com) Word origin: From Latin proboscis (Pliny), from Greek proboskis “elephant’s trunk,” literally “means for taking food,” from pro “forward” + boskein “to nourish, feed,” from boskesthai “graze, be...

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Prokaryote

/prōˈkarēˌōt/ Noun, pl. prokaryotes 1. Any of the group of organisms primarily characterized by the lack of true nucleus and other membrane-bound cell compartments: such as mitochondria and chloroplasts, and by the possession of a single loop of stable chromosomal DNA in the nucleiod region and cytoplasmic structures, such as plasma membrane, vacuoles, primitive cytoskeleton, and ribosomes. 2. Group of organisms, mostly unicellular, whose cells lack a cell nucleus (karyon). (wikipedia.com)   Word origin: from the Greek πρό- (pro-) “before” + καρυόν (karyon) “nut or...

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Proptosis

/präpˈtōsəs/ Noun 1. Forward projection or displacement especially of the eyeball. (biology-online.org) See also...

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Protein

/ˈprōˌtē(ə)n/  Noun, pl. proteins 1. Large biological molecule consisting of one or more chains of amino acids. Proteins perform a vast array of functions within living organisms, including catalyzing metabolic reactions, replicating DNA, responding to stimuli, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in folding of the protein into a specific three-dimensional structure that determines its activity. (wikipedia.org) 2. (Biochemistry) Any of numerous large, complex naturally-produced molecules composed of one or more long chains of amino acids, in which the amino acid groups are held together by peptide bonds. (wiktionary.org) 3. (Nutrition) One of three major classes of food or source of food energy (4 kcal/gram) abundant in animal-derived foods (ie: meat) and some vegetables, such as legumes. see carbohydrate and fat for the other two major classes. (wiktionary.org) 4. Any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids and are an essential part of all living organisms, esp. as structural components of body tissues such as muscle, hair, collagen, etc., and as enzymes and antibodies. (Google Dictionary) 5. Any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers...

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Protoplasm

/ˈprōtəˌplazəm/ Noun 1. The living contents of a cell that is surrounded by a plasma membrane. It is a general term for the cytoplasm. Protoplasm is composed of a mixture of small molecules such as ions, amino acids, monosaccharides and water, and macromolecules such as nucleic acids, proteins, lipids and polysaccharides. In eukaryotes, the protoplasm surrounding the cell nucleus is known as the cytoplasm and that inside the nucleus as the nucleoplasm. In prokaryotes, the material inside the plasma membrane is the bacterial cytoplasm, while in Gram-negative bacteria the region outside the plasma membrane but inside the outer membrane is the periplasm. (wikipedia.org) 2. The entire contents of a cell comprising the nucleus and the cytoplasm. It is a semi-fluid, transparent substance which is the living matter of plant and animal cells. (wiktionary.org) 3. The fluid living content of the cell that consists of two major divisions, the cytoplasm and the nucleoplasm (cell nucleus). It is composed mainly of nucleic acids, proteins, lipids, carbohydrates, and inorganic salts. (biology-online.org) 4. The organized colloidal complex of organic and inorganic substances (as proteins and water) that constitutes the living nucleus, cytoplasm, plastids, and mitochondria of the cell. (merriam-webster.com) 5. The colorless material comprising the living part of a cell, including the cytoplasm, nucleus, and other organelles. (Google Dictionary) Word origin: From German Protoplasma (1846), used by German botanist Hugo von Mohl (1805-1872),...

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