Glossary

Adenine

Or deoxyadenosine 5'-monophosphate (dAMP), a nitrogenous base of nucleotide in DNA and RNA

Amino acids

The fundamental building blocks of all proteins

Anaphase

The third stage of mitosis

Base Analogues

Chemicals that resemble a base

Buffer Solution

A solution used in PCR and electropherisis to maintin pH and to provide magnesium/calcium ions

Cell division

The process of a cell dividing into new daughter cells

Centrioles

Centrioles look like a pair of short cylinders, oriented at right angles to each other, and spindle fibers are formed from them.

Centromere

A structure of chromosome, shaped like a knot and is connected to the spindle during cell division

Chromatids

Two identical duplicated chromosomes

Chromatin

Nuclear DNA-protein complex in non-dividing cells

Crossovers

Points where two different pairs of nonsister chromatids exchange their genetic information by breaking and reunioning

Cytoplasm

The material surrounding the nucleus of a cell

Cytosine

Or deoxycytidine 5'-monophosphate (dCMP), a nitrogenous base of nucleotide in DNA and RNA

ddNTPs

Nucleotides lacking a 3' hydroxyl group making them incapable of bonding to the next nucleotide

Deoxyribonucleic acid

Or DNA in short form, the genetic material of almost all living things, which can be found in the cell nucleus and controls all cellular activities and heredity

Deoxyribose

A five-carbon sugar molecule which is a component of deoxyribonucleotide

Diploid organisms

Organisms whose chromosomes in each cell exist in pairs

DNA

Deoxyribonucleic acid, the genetic material of almost all living things, which can be found in the cell nucleus and controls all cellular activities and heredity

DNA polymerase

An enzyme that catalyse the extension of a new DNA strand during DNA replication

DNA replication

The process that DNA is duplicated to form exact copies of itself

Drosophila melanogaster

A fruit fly for investigating and discovering the structure and function of chromosomes

Electrophilic

Chemicals with high electronegativity. They attract electrons

Erythrocyte

The kind of cell in our blood that is responsible for transporting oxygen

Frameshift mutation

A type of mutation in which a pair of bases is lost or inserted

Genes

Occupy specific locations on the chromosomes

Guanine

Or deoxyguanosine 5'-monophosphate (dGMP), a nitrogenous base of nucleotide in DNA and RNA

Haemoglobin

A kind of pigment in erythrocytes. It binds with oxygen to increase the oxygen carrying capacity of them.

Haploid number

The reduced number of chromosomes in the sex cells

Histones

Proteins that pack DNA within chromosomes

Hybridization

The process in which a single stranded fragment matches with its partner in a single stranded DNA

Interphase

The stage before cell division when the DNA in the cell nucleus replicates to form two identical copies of each of the DNA molecules

Karyotypes

Photographs of banded chromosomes

Lysis

When a virus invades a cell, it will make use of the materials in the cytoplasm of that cell to reproduce. The offsprings then burst (lyse) the cell to continue invading other cells. The process in which the offsprings burst the cell is called lysis.

M-RNA

"Messenger" ribonucleic acid, carries the genetic codes transcribed from DNA to ribosomes

Melenin

A dark pigment that is present on our skin to prevent UV burns

Messenger Ribonucleic Acid

Or m-RNA in short form, carries the genetic codes transcribed from DNA to ribosomes

Metaphase

The second stage of cell division when the chromatids are being moved to the middle of the cell by the spindle fibers

Mitochondrion

A rod-shaped organelle which is a site of aerobic respiration and contains enzymes that help to release energy during respiration

Mitosis

Mitosis is a type of cell division where a cell splits into two with the same exact genetic information.

Morgan, Thomas Hunt (1866-1945)

The first to investigate and had discovered the structure and function of chromosomes by researching on the fruit fly, Drosophila melanogaster

Nitrogenous base

Especially refers to organic ring compounds containing nitrogen, such as adenine, thymine, guanine, cytosine and uracil

Nonhistone chromosomal protein

A protein that further packs the nucleosomes together into a dense, narrow coil

Nuclear envelope

A double membrane surrounding the nucleoplasm

Olignucleotide

A fragment of nucleotides

Oncogene

Genes or groups of genes that cause a cell to transform into a cancer cell

Organelles

Cell organs

PCR

Polymerase Chain Reaction. This technique is developed to duplicate DNA fragments in a short time with high purity.

Photomicrographs

Photographs of dividing cell nucleus

Plasma Membrane

The outermost layer of a human cell which encloses all the contents of a cell

Point Mutation

A type of mutation in which a base is changed into another

Primer

The segment of RNA to initiate DNA synthesis in DNA replication

Prophase

The first stage of cell division that the chromatin condenses and the chromosomes become visible

Protein

Proteins are composed of amino acids. Structures and functions of proteins are determined by the sequences of their amino acids

Protein synthesis

The process of tapping the genetic code to create proteins

Proto-Oncogene

These are genes in normal body cells, which control cell division

Purine

A nucleotide which composed of two rings, a six-membered ring fused with a five-membered ring, in its nitrogenous base

Pyrimidine

A nucleotide which has a single six-membered ring in its nitrogenous base

Radiation

Electromagnetic waves with frequency and energy much higher than UV

Replication fork

The place where the two strands of DNA separate

Replication of DNA

The process that DNA is duplicated to form exact copies of itself

Ribonucleic acid

Or RNA in short form, can be found in the cell nucleus and the cytoplasm, and involves in protein synthesis and replication of DNA

Ribose

Five-carbon sugar molecule which forms part of ribonucleotide

Ribosome

A site for protein synthesis which is responsible to hold the m-RNA in place and to coordinate the activities of the enzymes

RNA

Ribonucleic acid, which can be found in the cell nucleus and the cytoplasm, and involves in protein synthesis and replication of DNA

RNA polymerase

An enzyme that catalyse the formation of RNA

Spindle

Consists of fibers to move the centromeres and cause the rest of each chromosome to follow. This ensures each chromosome moves to its appropriate place during cell division.

Suicide Enzyme

Enzymes that are not reusable

T-RNA

"Transfer" ribonucleic acid, is responsible for major translation work during protein synthesis

Tautomeric Shift

A type of point mutation where tautomers of purines and pyrimidines are formed

Telomerase

An enzyme that directs the replication of telemeres

Telomere

Specialized and repeated sequences of DNA found at the ends of chromosomes to protect and prevent the ends of chromosomes attaching to each other

Telophase

The fourth and the last stage of mitosis

Thymine

Or deoxythymidime 5'-monophosphate (dTMP), a nitrogenous base of nucleotide in DNA

Transcription

First step of protein synthesis which copies the code of DNA in the nucleus to the m-RNA

Transfer Ribonucleic Acid

Or t-RNA in short form, is responsible for major translation work during protein synthesis

Translation

The process of translation is to translate genetic code to the language of proteins

Uracil

A nitrogenous base of nucleotide in RNA

UV

Ultra Violet, an range of electromagnetic wave of fairly high frequency. It also carries a fairly high amount of energy