Biology terminology
DNA: code of life
DNA Deoxyribonucleic acid; made up of monomers called nucleotides with
nitrogenous bases A, T, C and G; carries the genetic code for protein
synthesis.
RNA Ribonucleic acid; there are 3 types of RNA: mRNA, tRNA and rRNA
each of which play particular roles in protein synthesis.
Protein synthesis Process by which amino acids are linked together in a particular
sequence to form a required protein.
Chromosome String-like structure found in the nucleus of dividing cells; formed from
chromatin network; contains the hereditary material DNA.
Nuclear Membrane surrounding the nucleus.
membrane
Chromatin An entangled mass of threads found in the nucleus of cells which are in
network resting stage (not dividing); they give rise to chromosomes.
Nucleolus Structure in the Nucleus in which rRNA (ribosomal RNA) is synthesized.
Nucleotide A monomer which forms DNA and RNA; each nucleotide is made up of
sugar, a phosphate ion and a nitrogenous base.
Nuclear DNA DNA found in the nucleus of cells, is made up of genetic material from
both parents.
Extra-nuclear DNA that is located outside the nucleus such as mitochondrial DNA.
DNA
Mutation Sudden, random changes in the genetic code of an organism which can
be inherited.
Deoxyribose A sugar that is part of a DNA molecule.
Complimentary Nitrogenous bases that always pair with each other and are joined by
base pairs weak hydrogen bonds in DNA molecules. E.g. guanine and cytosine &
adenine and thymine.
Double helix The shape of the DNA molecule that consists of 2 strands joined to each
other which are spirally twisted.
Adenine 1 of 4 nitrogenous bases found in DNA and RNA; in DNA it joins with
thymine, in RNA it joins with uracil.
Guanine 1 of 4 nitrogenous bases found in DNA and RNA; joins with cytosine in
DNA and RNA.
Cytosine 1 of 4 nitrogenous bases found in DNA and RNA; Joins to guanine in
DNA and RNA.
Thymine 1 of 4 nitrogenous bases found in DNA; not found in RNA; pairs with
adenine in DNA.
Weak hydrogen Bonds holding nitrogenous bases together in DNA.
bond
Gene A small portion of DNA which carries the genetic code for the formation
of a particular trait or characteristic; it also carries the code for proteins.
Non-coding DNA Portions of DNA that do not code for specific amino acids.
Mitosis A type of cell division which results in 2 cells which are genetically
identical to each other and to the parent cell (which no longer exists).
Meiosis A type of cell division where the nucleus divides twice but the
chromosomes duplicate once only, resulting in 4 cells each with half the
chromosome number as the original.
DNA replication Process by which 2 identical DNA molecules are formed from 1 DNA
molecule; occurs just before cell division.
Interphase The stage in mitosis during which DNA replication takes place.
Template Strand of DNA upon which another strand of DNA is built during
replication or mRNA is built during protein synthesis.
, Complementary The new DNA strand that is developed during DNA replication according
strand to the template strand of DNA, using free nucleotides.
Fingerprints Imprint of the pattern on a finger that is unique to all individuals except
identical twins.
DNA ‘fingerprint’ The unique pattern formed by the DNA fragments of an individual.
DNA profiling The process by which a DNA ‘fingerprint’/profile of an individual is
obtained.
Inherited disorder A disorder that can be passed on from one generation to the next since it
is controlled by a particular gene.
Forensic science The application of a broad spectrum of sciences and technologies to
investigate and establish facts of interest in relation to criminal or civil
law.
Amino acid The monomers which serve as building blocks for the synthesis of
proteins.
Protein A complex organic compound made up of a long chain of amino acids.
Dipeptide Molecule consisting of 2 amino acids.
Polypeptide A long chain of amino acids linked together by peptide bonds.
Dehydration The process by which small molecules combine to form longer ones with
synthesis water being released during the process.
Transcription Synthesis of mRNA from DNA, by complimentary matching of the
nitrogenous bases in DNA.
Translation Part of protein synthesis involving the combination of amino acids
according to codons on mRNA.
Codon A sequence of 3 consecutive bases found in mRNA onto which fit 3
complimentary bases of tRNA during protein synthesis.
Anticodon Sequence of 3 consecutive bases on tRNA which complement the bases
on the codon found on mRNA.
mRNA Messenger RNA.
tRNA Transfer RNA.
Ribosome Small grain like structure found in the cytoplasm which are the sites of
protein synthesis.
DNA: code of life
DNA Deoxyribonucleic acid; made up of monomers called nucleotides with
nitrogenous bases A, T, C and G; carries the genetic code for protein
synthesis.
RNA Ribonucleic acid; there are 3 types of RNA: mRNA, tRNA and rRNA
each of which play particular roles in protein synthesis.
Protein synthesis Process by which amino acids are linked together in a particular
sequence to form a required protein.
Chromosome String-like structure found in the nucleus of dividing cells; formed from
chromatin network; contains the hereditary material DNA.
Nuclear Membrane surrounding the nucleus.
membrane
Chromatin An entangled mass of threads found in the nucleus of cells which are in
network resting stage (not dividing); they give rise to chromosomes.
Nucleolus Structure in the Nucleus in which rRNA (ribosomal RNA) is synthesized.
Nucleotide A monomer which forms DNA and RNA; each nucleotide is made up of
sugar, a phosphate ion and a nitrogenous base.
Nuclear DNA DNA found in the nucleus of cells, is made up of genetic material from
both parents.
Extra-nuclear DNA that is located outside the nucleus such as mitochondrial DNA.
DNA
Mutation Sudden, random changes in the genetic code of an organism which can
be inherited.
Deoxyribose A sugar that is part of a DNA molecule.
Complimentary Nitrogenous bases that always pair with each other and are joined by
base pairs weak hydrogen bonds in DNA molecules. E.g. guanine and cytosine &
adenine and thymine.
Double helix The shape of the DNA molecule that consists of 2 strands joined to each
other which are spirally twisted.
Adenine 1 of 4 nitrogenous bases found in DNA and RNA; in DNA it joins with
thymine, in RNA it joins with uracil.
Guanine 1 of 4 nitrogenous bases found in DNA and RNA; joins with cytosine in
DNA and RNA.
Cytosine 1 of 4 nitrogenous bases found in DNA and RNA; Joins to guanine in
DNA and RNA.
Thymine 1 of 4 nitrogenous bases found in DNA; not found in RNA; pairs with
adenine in DNA.
Weak hydrogen Bonds holding nitrogenous bases together in DNA.
bond
Gene A small portion of DNA which carries the genetic code for the formation
of a particular trait or characteristic; it also carries the code for proteins.
Non-coding DNA Portions of DNA that do not code for specific amino acids.
Mitosis A type of cell division which results in 2 cells which are genetically
identical to each other and to the parent cell (which no longer exists).
Meiosis A type of cell division where the nucleus divides twice but the
chromosomes duplicate once only, resulting in 4 cells each with half the
chromosome number as the original.
DNA replication Process by which 2 identical DNA molecules are formed from 1 DNA
molecule; occurs just before cell division.
Interphase The stage in mitosis during which DNA replication takes place.
Template Strand of DNA upon which another strand of DNA is built during
replication or mRNA is built during protein synthesis.
, Complementary The new DNA strand that is developed during DNA replication according
strand to the template strand of DNA, using free nucleotides.
Fingerprints Imprint of the pattern on a finger that is unique to all individuals except
identical twins.
DNA ‘fingerprint’ The unique pattern formed by the DNA fragments of an individual.
DNA profiling The process by which a DNA ‘fingerprint’/profile of an individual is
obtained.
Inherited disorder A disorder that can be passed on from one generation to the next since it
is controlled by a particular gene.
Forensic science The application of a broad spectrum of sciences and technologies to
investigate and establish facts of interest in relation to criminal or civil
law.
Amino acid The monomers which serve as building blocks for the synthesis of
proteins.
Protein A complex organic compound made up of a long chain of amino acids.
Dipeptide Molecule consisting of 2 amino acids.
Polypeptide A long chain of amino acids linked together by peptide bonds.
Dehydration The process by which small molecules combine to form longer ones with
synthesis water being released during the process.
Transcription Synthesis of mRNA from DNA, by complimentary matching of the
nitrogenous bases in DNA.
Translation Part of protein synthesis involving the combination of amino acids
according to codons on mRNA.
Codon A sequence of 3 consecutive bases found in mRNA onto which fit 3
complimentary bases of tRNA during protein synthesis.
Anticodon Sequence of 3 consecutive bases on tRNA which complement the bases
on the codon found on mRNA.
mRNA Messenger RNA.
tRNA Transfer RNA.
Ribosome Small grain like structure found in the cytoplasm which are the sites of
protein synthesis.
