Unit 1: Cells And Proteins Flashcards
(74 cards)
Actin
Globular protein which forms microfilaments. Associated with myosin for cell movement.
Affinity
The degree to which a substance tends to combine with another
Allosteric enzymes
Enzymes which change conformation in response to a modulator which binds at a secondary binding site
Alpha helix
Polypeptide chain coiled into a helix with hydrogen by ding occurring to maintain the arrangement
Alternative RNA splicing
Removal of non-coding introns from a primary mRNA transcript to leave only the coding expand. Several mature transcripts can be produced from a single primary transcript.
Antibody
Y-shapes globular protein with specificity to an antigen
Apoptosis
Programmed cell death in response to damage to DNA etc
Aquaporin
Integral channel forming proteins within the membrane which selectively allow movement of water molecules across the membrane
AQP2 (aquaporin 2)
Channel protein found in the collecting duct of the kidneys. They are triggered to move to the cell surface by ADH and allow increased reabsorption of water into the bloodstream
Aseptic techniques
Procedures in place to prevent contamination including sterilisation of equipment and work surfaces
Bacteriorhodopsin
Light absorbing molecule found in Archae (one of the three domains of life, the other two being bacteria and eukaryota) It pumps protons across the membrane creating a proton gradient which can then be used to generate ATP
Beta sheets
Polypeptide chain arranged in rows with the chain coiling in parallel or anti parallel arrangements
Buffer
A solution used to set and maintain a particular pH
Caspase cascade
Caspase proteins are involved in a series of reactions (a cascade) which destroys a cell
Cell cycle checkpoints
Checkpoints which assess the readiness of a cell to enter the next stage of the cell cycle. They occur during G1, G2 and Metaphase
Centrifuge
Apparatus which spins very quickly to desperate materials due to their density. Heavier components move to the bottom of the tube
Centrosome (MTOC)
Microtubules radiate from the centrosome and are active during cell division as microtubules form the spindle fibres
Chromatography
A separating technique in which there is a stationary phase (paper or gel) which the mobile phase (solvent) moves through carrying the substance being examined. Different substances have different solubility in each so move different distances
Cooperativity
Proteins composed of several polypeptides (subunits) can show cooperativity. Changes in binding of one subunit give the other subunits a greater affinity for the molecule e.g. Binding of oxygen to one haemoglobin subunit gives the other subunits a greater affinity for oxygen
Complex media
A nutrient rich growth medium providing all basic requirements for cell growth: amino acids, glucose, salts, water. They also may contain specific growth factors required for animal cell lines
Cyclin
Proteins that control the progression of cells through the cell cycle by activating cyclin- dependant kinase (Cdk) enzymes
Cyclin dependant kinases (Cdks)
When activated by cyclin, Cdks cause the phosphorylation of proteins which stimulate the cell cycle
Cytoskeleton
A microscopic network of protein filaments and tubules in the cytoplasm of many living cells, which support their shape and function
Type 1 diabetes
Diabetes is the inability to regulate blood glucose levels. Type one is caused by the failure to produce insulin