Life Sciences

Life Sciences is another very popular foundation module among NatScis! This module sets the stage for future choices in molecular biology, neuroscience, biomed, and genetics.

The table below covers some of the molecular biology which is covered in the foundation module.

Acidic   Refers to a substance that releases protons when dissolved in water. Has a pH of below 7. 
Action potential   a change in the electrical potential across a nerve cell membrane that reverses polarisation of the membrane and allows propagation of an electrical impulse.  
Active transport   The movement of ions or molecules across a membrane from an area of low concentration to high concentration (against the electrochemical gradient), requiring energy. 
Adenine, cytosine, guanine, thymine and uracil  The five bases that can be present on nucleotides. A,C,G and T are presented on DNA nucleotides/monomers and T is replaced with U in RNA nucleotides/monomers. 
Amine group  a functional group consisting of a nitrogen atom with a lone pair of electrons. 
Amino acid  A small organic molecule with both amino and carboxyl functional groups. Are monomers and polymerise to form proteins. 
Anaerobic   Metabolic reactions, for example respiration, that occur in the absence of oxygen. 
Anti-parallel   Parallel (continuously the same distance apartbut moving in opposite directions. Refers to the two strands of a DNA helix.  
Apoptosis   Programmed cell death wherein the cell constituents are broken down during foetus development and to eliminate damaged/infected cells. 
Aqueous   in reference to a solution; containing water. A water environment. 
ATP (adenosine triphosphate)   A molecule containing a nucleotide and three phosphate groups. The terminal phosphate is removed and reattached to transfer energy inside cells for metabolic reactions, for example active transport.  
Autonomic   In reference to the nervous system; the involuntary system that regulated activity of internal organs.  
Autophagy   The regulated cell mechanism of degrading and recycling dysfunctional components, for example misfolded proteins. 
Basic   Refers to a substance that accepts protons in aqueous solutions. Has a pH of above 7. 
Carrier protein  A transmembrane protein with a specific binding site for an ion or molecule to transport that substance over the plasma membrane. 
Chaperonin   Proteins that provide favourable conditions for the correct folding of proteins. 
Chloroplast   An organelle containing chlorophyll that conducts photosynthesis in green plant leaves. 
Chromatid  When chromosomes have self-replicated, this is one of the two identical chromosomes.  
Chromatography   A technique to separate a mixture by passing it by suspension through a medium in which each component moves at a different rate. 
Chromosome   Structure formed by the condensation DNA and associated histone proteins in early stages of cell division.  
CNS (central nervous system)  The collective term for the brain and spinal cord. 
Cofactor   A non-protein chemical compound or metallic ion required for an enzyme’s function. 
Covalent bond  A chemical bond involving the sharing of electrons between atoms. 
Cytoplasm   A thick solution of water, salt and proteins that surrounds organelles in the cell and encased by the plasma membrane. 
Degenerate   Refers to the genetic code because each amino acid may be coded for by more than one codon (set of 3 bases). 
Denaturation  Disruption of the three dimensional structure of a protein by breakage of weak hydrogen bonds, thus altering or stopping the function that protein. Caused by exposure to pH change or raised temperature. 
Diffusion   Passive movement of a substance from a region of high concentration to an area of lower concentration of that substance.  
Electrochemical gradient   The tendency of an ion to move from one side of a membrane to another, considering the electrical charge, concentration gradient and potential difference across the membrane. 
Endoplasmic reticulum   An organelle consisting of a system of enclosed membranes. The Rough ER has ribosomes attached to synthesise proteins and smooth ER synthesises lipids.  
Enzyme   Proteins that regulate the rate of metabolic reactions without being used up or altered.  
Epidermis   A layer of tissue that covers the outer surface of a structure, e.g. the body or a plant. 
Eukaryote   Multi-celled organisms that have a nucleus enclosed in a membrane. They have membrane bound organelles. 
Excitatory   In reference to postsynaptic potential, a postsynaptic potential that makes the neuron more likely to fire an action potential.  
Genome   The complete set of genetic material contained in each cell, including genes, non-coding DNA, mitochondrial DNA, and for plants, chloroplast DNA. 
Helix   A shape like a corkscrew or a spiral, characteristic of DNA 
Heredity   Also called inheritance, is the genetic passing of physical and mental characteristics from parents to offspring.  
Hormone   A chemical signal released into the blood by endocrine cells in order to regulate activity of another group of cells. 
Hydrophilic   A substance that is soluble in water.  
Hydrophobic   A substance that is only partially soluble or insoluble in water. 
Inhibitory   Of postsynaptic potential, decreases the likelihood of a neuron firing an action potential. 
In vitro  Studies of biological matter taken outside of their natural biological context, I.e carried out in a test tube, flask or petri dish. 
In vivo  Biological studies where the organism is studied as a whole organism rather than by tissue extract.  
Ion channel  A transmembrane protein that allows specific ions pass through the membrane. 
Ligand   A compound consisting of an ion or molecule (acting as functional group) attached to a central metal atom. 
Macromolecule   A large molecule that is composed of many covalently bonded atoms. 
Mitochondria   Membrane bound organelles that synthesise ATP through oxidative phosphorylation and have their own DNA called mtDNA. 
Motor neuron  A neuron/nerve cell that carries impulses from the brain or spinal cord to the effector muscle or secretory gland. 
Mutualistic   An ecological interaction between two species where each species benefits from said interaction.  
Neuron   Preferred name for a nerve cell, which is a cell specialised for transmitting electrical signals throughout the body. 
Neurotransmitter   A chemical signal released at the synaptic terminal to diffuse across the synapse and influence activity of the target cell by binding to it. 
Nucleic acid   The nucleic acids are DNA and RNA, which consist of long chains of nucleotides. DNA is a double stranded helix shape ad RNA is a single strand. 
Nucleotide   An organic compound that contains a base, pentose sugar and one or more phosphate groups. 
(cell) Nucleus   The largest organelle in each cell, containing all of the DNA and the nucleolus.  
Nucleolus   A region in the nucleus that contains protein and RNA, and synthesises ribosome subunits and RNA. 
Organelle   A discrete structure in a cell that has a specific function.  
Osmosis   The movement of water from an area of lower concentration to an area of higher concentration of solution through a semi-permeable membrane.  
Parallel   DNA strands are parallel because they run side by side with the same distance consistently between them. 
Peptide bond   The bond between the carboxyl group of one amino acid and the amino group of another amino acid.  
Phosphodiester bond   A covalent bond in DNA or RNA where a phosphate on the 5th carbon of one nucleotide bonds to the hydroxyl group on the 3rd carbon of another nucleotide. 
Phosphorylation   The addittion of a phosphoryl group (PO3-) to an organic molecule. 
Plasma membrane   The lipid membrane that covers the entire outer surface of a cell. 
Polar   The tendency of electrons in a bond to be associated with only one of the two atoms in the bond. Polar substances are soluble in water. 
Polymerase   An enzyme used in DNA replication to join together nucleotides as they pair up against the DNA template. 
Potential difference   Also called membrane potential, is the difference in charge between the inside and outside of the neuron.  
Primary structure   The simplest level of protein structure, this is just the sequence of amino acids in the polypeptide chain. 
Primer   A short nucleic acid sequence that acts as the starting point for DNA synthesis.  
Prokaryote   microscopic single-celled organism that does not have a nucleus or organelles that are membrane bound.  
Promoter region   a region of DNA where transcription of a gene is initiated. Where RNA polymerase binds.  
Prosthetic group   A non-protein chemical or a metal ion that is required to combine to a protein such as an enzyme for it to function.  
Protease   An enzyme that catalyses proteins into smaller polypeptides and single amino acids. 
Protein   nitrogenous organic compound.  
Purine   Describes the adenine and guanine bases that are part of nucleotides. They are based on a double ring structure therefore are larger than pyramidines.  
Pyrimidine   Describes the cytosine, thymine and uracil bases that are part of nucleotides. Based on a single ring structure so are smaller than purines. 
Quaternary structure   The final level of protein structure that is the number and arrangement of protein subunits into a multi-subunit structure.  
Relay neuron  Neurons found in the brain and spinal cord to connect sensory neurons at the input and motor neurons at the output. 
Respiration   The biochemical reaction inside every living cell to obtain energy by oxidising glucose. 
RNA (ribonucleic acid)  Single stranded copies of sections of DNA. There are multiple types involved in the translation and transcription of DNA. 
Secondary structure   Recurring arrangements of adjacent amino acids in the chain, held together by hydrogen bonds to form an alpha helix or beta pleated sheet. 
Semiconservative   Describes DNA repliction because each molecule of DNA is comprised of one original strand and one newly formed strand.  
Senescence   Loss of a cell’s ablity to divide and grow – deterioration.  
Sense and anti sense   Refers to the two stands of DNA. Sense runs in the 5’ to 3’ direction and contains the translatable code, which is complimentary and thus opposite to the anti-sense strand.  
Sensory neuron  The input neuron where external stimuli are converted into electrical impulses.  
Somatic   Relates to the body. 
Specialised   Cells that have developed particular characteristics for a specific function.  
Symbiosis   Close, long-term, physical interaction of two organisms to the advantage of both.  
Synapse   The junction between a nerve ending/ axon terminal and the next target cell, eg a neuron, mescle or gland.  
Telomere   A region of repetitive nucleotide sequences at the end of a chromosome to protect the ends from fusing or deteriorating.  
Tertiary structure   The overall three dimensional shape of a single polypeptide.  
Transcription   The process by which the information in a strand of DNA is copied into a smaller, single stranded molecule called messenger RNA that is able to leave the nucleus.  
Translation   The process by which ribosomes form proteins after transcription has occurred.  
Truncated   Shortened by cutting off the end.  
Ubiquitination   The process by which proteins are marked and targeted for degradation.  
Vesicle   A structure present inside and out of cells that can pass through the membrane to transport substances. It is comprised of a liquid cytoplasm enclosed in a lipid bilayer.  
XNA (xenonucleic acid)  Synthetic nucleic acids with a different sugar backbone to DNA and RNA.