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Endoplasmic Reticulum
The endoplasmic reticulum (ER) is an eukaryotic organelle that forms an interconnected network of tubules, vesicles, and cisternae within cells. TERM 2
Flagellum
DEFINITION 2 A flagellum (, or in plural form: flagella) is a tail-like projection that protrudes from the cell body of certain prokaryotic and eukaryotic cells, and functions in locomotion. TERM 3
Centrosome
DEFINITION 3 In cell biology, the centrosome is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell as well as a regulator of cell-cycle progression. TERM 4
Nuclear Envelope
DEFINITION 4 The nuclear envelope (NE) (also known as the perinuclear envelope, nuclear membrane, nucleolemma or karyotheca) is a double lipid bilayer that encloses the genetic material in eukaryotic cells. TERM 5
Cytoskeleton
DEFINITION 5 The cytoskeleton (also CSK) is a cellular "scaffolding" or "skeleton" contained within the cytoplasm and is made out of protein.
Microvilli
Microvilli (singular: microvillus) are microscopic cellular membrane protrusions that increase the surface area of cells, and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction. TERM 7
Peroxisome
DEFINITION 7 organelle with various specialized functions; produces hydrogen peroxide as a by product then converts it to water TERM 8
Mitochondrion
DEFINITION 8 In cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed organelle found in most eukaryotic cells. Organelle where cellular respiration occurs and most ATP is generated. TERM 9
Lysosome
DEFINITION 9 Lysosomes are cube shaped organelles that contain enzymes (acid hydrolases) that break up waste materials and cellular debris. Digestive organelle where macromolecules are hydrolyzed TERM 10
Golgi Apparatus
DEFINITION 10 Organelle active in synthesis, modification, sorting and secretion of cell products
Nucleolus
The nucleolus (also called nucleole) is a non-membrane bound structure composed of proteins and nucleic acids found within the nucleus. TERM 17
Chromatin
DEFINITION 17 Chromatin is the combination of DNA and proteins that makes up chromosomes. Material consisting of DNA and proteins; visible as individual chromosomes in a dividing cell TERM 18
Central Vacuole
DEFINITION 18 A vacuole is a membrane bound organelle which is present in all plant and fungal cells and some protist, animal and bacterial cells. Prominent organelle in older plant cells; functions include storage, breakdown of waste products, hydrolysis of macromolecules; enlargement of vacuole is a major mechanism for plant growth TERM 19
Chloroplast
DEFINITION 19 Chloroplasts are organelles found in plant cells and other eukaryotic organisms that conduct photosynthesis. Converts energy of sunlight to chemical energy stored in sugar molecules TERM 20
Cell
Wall
DEFINITION 20 Outer layer that maintains cells shape and protects cell from mechanical damage; made of cellulose, other polysaccharides, and protein
Cell
Fractionation
Cell fractionation is the separation of homogeneous sets, usually organelles, from a heterogeneous population of cells. TERM 22
Dehydration Reaction
DEFINITION 22 In chemistry and the biological sciences, a dehydration reaction is usually defined as a chemical reaction that involves the loss of water from the reacting molecule. TERM 23
Enzymes
DEFINITION 23 Enzymes are proteins that catalyze (i.e., increase the rates of) chemical reactions. TERM 24
Hydrolysis
DEFINITION 24 Hydrolysis is a chemical reaction during which molecules of water (H2O) are split into hydrogen cations (H+) (conventionally referred to as protons) and hydroxide anions (OH) in the process of a chemical mechanism. TERM 25
Carbohydrates
DEFINITION 25 Include both sugars and polymers of sugars. Examples: Monosaccharides, Disaccharides, Polysaccharides
Glucose
Glucose (C6H12O6), a simple sugar (monosaccharide), is an important carbohydrate in biology. In aqueous solutions, glucose molecules, as well as most other sugars form rings. TERM 32
Glycogen
DEFINITION 32 Glycogen is the molecule that functions as the secondary long-term energy storage in animal and fungi cells. Polysaccharide. Glycogen stores are depleted in about a day unless they are replenished by consumption of food. TERM 33
Cellulose
DEFINITION 33 Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand (14) linked D-glucose units. The glucose molecules of cellulose are in the beta configurations. Cellulose is never branched, and some hydroxyl groups on its glucose monomers are free to hydrogen bond with the hydroxls of other cellulose molecules lying parallel to it TERM 34
Chitin
DEFINITION 34 Chitin (C8H13O5N)n () is a long-chain polymer of a N- acetylglucosamine, a derivative of glucose. used by arthropods for there exoskeletons. Chitin is similar to cellulose except that the glucose monomer of chitin has a nitrogen-containing appendage TERM 35
Lipids
DEFINITION 35 Lipids are a broad group of naturally occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. Mix very poorly with water. Lipids consist of mostly hydrocarbon regions
Fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. Constructed of two kinds of smaller molecules; glycerol and fatty acids. In making a fat three fatty acids bond to a glycerol. TERM 37
Glycerol
DEFINITION 37 Glycerol is an organic compound, also called glycerin or glycerine. Consists of a alcohol with three carbons. These carbons all bear a hydroxyl group TERM 38
Fatty Acid
DEFINITION 38 a fatty acid is a carboxylic acid with a long unbranched aliphatic tail (chain), which is either saturated or unsaturated. Long carbon skeleton usually consisting of 16 to 18 carbon atoms. This is also known as a triacylglycerol TERM 39
Unsaturated fat
DEFINITION 39 An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. TERM 40
Saturated fatty
acid
DEFINITION 40 Saturated fat is fat that consists of triglycerides containing only saturated fatty acid radicals. No double bonds within the carbon chain. Major contributor of atherosclerosis
Cholesterol
Cholesterol is a waxy steroid metabolite found in the cell membranes and transported in the blood plasma of all animals. Precursor for which steroids are synthesised TERM 47
Proteins
DEFINITION 47 Proteins (also known as polypeptides) are organic compounds made of amino acids arranged in a linear chain and folded into a globular form. Proteins account for more than 50% of the dry mass of most cells. Proteins speed up chemical reactions, structural support, storage, transport, cellular communication, movement and defense against foreign substances. The most structurally sophisticated molecule. Consists of one or more polypeptide, each folded and coiled into a specific three-dimensional structure TERM 48
Polypeptides
DEFINITION 48 Peptides are short polymers of amino acids linked by peptide bonds. TERM 49
Catalysts
DEFINITION 49 Chemical agents that selectively speed up chemical reactions without being consumed by the reaction TERM 50
Amino Acids
DEFINITION 50 Amino acids are molecules containing an amine group, a carboxylic acid group and a side chain that varies between different amino acids. At the center of an amino acid is an asymmetric carbon atom called the alpha carbon. The physical and chemical properties of the side chain determine the unique characteristics of a particular amino acid, thus affecting its functional role in a polypeptide.
Peptide Bond
When two amino acids are positioned so that the carboxyl group of one is adjacent to the amino group of the other, they can become joined by a dehydration reaction, with the removal of a water molecule. This process yields a polypeptide, a polymer of many amino acids linked by peptide bonds TERM 52
Primary structure of Proteins
DEFINITION 52 The primary structure of peptides and proteins refers to the linear sequence of its amino acid structural units. TERM 53
Secondary Structure of Proteins
DEFINITION 53 In biochemistry and structural biology, secondary structure is the general three-dimensional form of local segments of biopolymers such as proteins and nucleic acids (DNA/RNA). TERM 54
Pleated Sheet
DEFINITION 54 The sheet (also -pleated sheet) is the second form of regular secondary structure in proteins, only somewhat less common than alpha helix. TERM 55
Alpha Helix
DEFINITION 55 A common motif in the secondary structure of proteins, the alpha helix (-helix) is a right-handed coiled or spiral conformation, in which every backbone N-H group donates a hydrogen bond to the backbone C=O group of the amino acid four residues earlier ( hydrogen bonding).
Chaperonins
protein molecules that assist in the proper folding of other proteins TERM 62
X-Ray Crystallography
DEFINITION 62 X-ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X- rays strikes a crystal and diffracts into many specific directions. TERM 63
Gene
DEFINITION 63 A gene is a unit of heredity in a living organism. TERM 64
Nucleic Acids
DEFINITION 64 A nucleic acid is a macromolecule composed of chains of monomeric nucleotides. DNA TERM 65
Deoxyribonucleic Acid
DEFINITION 65 Deoxyribonucleic acid () (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms with the exception of some viruses. Directs the RNA in protein synthesis. Without oxygen (Deoxyribose sugar) Chemical groups associated with DNA: thymine
Ribonucleic Acid
Ribonucleic acid (RNA) is a biologically important type of molecule that consists of a long chain of nucleotide units. Controls protein synthesis. With oxygen (Ribose sugar) Chemical groups associated with RNA: Uracil TERM 67
mRNA
DEFINITION 67 Messenger RNA (mRNA) is a molecule of RNA encoding a chemical "blueprint" for a protein product. TERM 68
polynucleotides
DEFINITION 68 nucleic acids are macromolecules that exist as polymers. consists of monomers called nucleotides. TERM 69
Nucleotides
DEFINITION 69 Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. A nucleotide is itself composed of three parts: a nitrogenous base, a five carbon sugar, and a phosphate group. The portion of this unit without the phosphate group is called a nucleoside. TERM 70
Pyrimidine
DEFINITION 70 Pyrimidine is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 3 of the six-member ring. The members of the pyrimidine family are cytosine, thymine, and uracil.
