Unit 1 KA 1.2 ✓ Flashcards
Proteins (25 cards)
What is an organisms Genome?
An organisms genome is its complete set of DNA
NOTE: Not all of this DNA codes for proteins
What is an organisms Proteome?
An organisms proteome is the entire set of proteins that can be expressed using an organisms genome
NOTE: The proteome is much larger than the genome - alternative splicing
What is an Exon?
An exon is a coding region in DNA, it can be left in or removed during transcription to produce different mature RNA transcripts (alternative splicing).
NOTE: Introns are non-coding regions
What is a Eukaryote?
A eukaryote is a cell which has a clearly defined nucleus
In terms of membrane bound organelles:
What is an Intracellular membrane?
NOTE: Remember intra = IN the cell
A membrane that helps with protein synthesis and transport in a cell
e.g. Eukaryote cells need this as they dont have enough membrane to perform vital functions
(Membrane bound organelle)
What is the Endoplasmic reticulium?
(Smooth ER and Rough ER)
The ER is a series of membrane tubules that extend from the nuclear membrane. RER has ribosomes along its surface, SER does not
What are Lipids?
(Where are they synthesised?)
Lipids make up part of the plasma membrane (phospholipid bilayer), they form the hydrophobic lipid tails.
They are synthesised in the smooth endoplasmic recticulium (SER)
What is a Cytosolic protein?
A cytosolic protein is a protein which is synthesised at a cytosolic ribosome (a ribosome in the cytosol) and it remains in the cytosol
What is a Transmembrane protein?
A transmembrane protein is a protein which is permanantly attached to a membrane, it is synthesised at a cystolic ribosome (ribosome in the cytosol)
(Membrane bound organelle)
What is the Golgi apparatus?
The golgi apparatus is a series of flattened mebrane disks that proteins can pass through to be modified
What is the major Post translational modification that occurs in the Golgi?
The addition of carbohydrates to form a glycoprotein is a major post translational modification that occurs in the Golgi
(Membrane bound organelle)
What are Lysosomes?
Lysosomes contain hydrolases (enzymes) that break down the covalent bonds of proteins, lipids, nucleic acids and carbohydrates using water
(Membrane bound organelle)
What are Vesicles?
Vesicles transport proteins and other substances around the cell
NOTE: They ‘walk’ along microtubules between organelles
What are Microtubules?
Microtubules are cytoskeleton structures that vesicles “walk” along between organelles in the cell
What is the Cytosol?
The cytosol is the fluid in which organelles are suspended
What is the Cytoplasm?
The cytoplasm is the cytosol and all the organelles (not the nucleus) within the plasma membrane of a cell
What is a Signal sequence?
A signal sequence is a string of amino acids that determines the final location of a protein in a cell and signals a ribosome to dock with the endoplasmic recticulium
What Post translational modification occurs to secretory proteins?
Proteolytic cleavage is the post translational modification that occurs to secretory proteins
What are Monomers?
Monomers are the building blocks that make up polymers
e.g. Amino acids join with peptide bonds to make proteins
What is a Polypeptide?
A polypeptide is a long chain of amino acids joined together with peptide bonds
NOTE: Remember poly(many) peptide(peptide bonds)
What is the R group of an amino acid?
The R group of an amino acid is the variable section that determines the properties of the amino acid
What is a Prosthetic group?
A prosthetic group is a non protein subunit in a protein with quaternary structure
What is a Ligand?
A ligand is a substance that can bind to a protein and cause a conformational change in the protein
What is a Modulator? (+/-)
A modulator binds to allosteric sites on a protein, changing the conformation of the active site
(+ modulators increase affinity, - decreases affinity)
