Unit 1 KA2 Flashcards
What is the proteome?
It is all the proteins made from all the genome
In eukaryotic cells, what size is the proteome compared to the genome. (2 points) Why? (3 points)
- Larger
- Because alternative RNA splicing allows for more than one protein to be expressed
Not all genes are expressed as…
Proteins in a particular cell type
What can happen to the set of proteins expressed over time?
They can vary because of certain conditions
Name the factors that can affect types of proteins expressed
- Metabolic activity
- Cellular stress
- Response to signalling molecules
- Disease
Give an example of metabolic activity
Age
Dormancy state
Give an example of cellular stress
Extremes of:
- temperature
- pH
-exposure of toxins
Give an example of a response to signalling molecules
Hormones
What can RNA genes be transcribed to produce?
tRNA, rRNA, mRNA, RNA molecules that
1. Control gene expression of other genes
2. Protection of telomeres
Alternative RNA Splicing
definition
Removal of non-coding introns from a primary mRNA transcript to leave only the coding exons; several different mature transcripts can be produced from a single primary transcript
ER
what does it stand for and what is the definition?
- endplasmic reticulum
- a network of membrane tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane
exon
definition
a section of RNA that is usually retained in splicing
Glycoprotein
definition
a protein with a carbohydrate added by post-translational-modification
Golgi Apparatus
how is it identifiable? definition.
- it is a series of membrane discs
- it packages proteins into membrane bound vesicles inside the cell before the vesicles are sent to their destination
looks like pancakes, acts as the amazon of the cell
Hydrolases
a class of enzymes that use water the break chemical bonds
intron
a section of RNA that is usually removed during splicing
Lysosome
definition
a modified golgi vesicle containing hyrolytic enzymes
Non-coding RNA gene
A gene that codes for RNAs other than mRNA so do not code for a protein
phospholipid
definition
component of cell membranes
post-translational modification
definition
addition of different chemical groups to, or modification of, a protein to allow a particular function
Proteolytic cleavage
definition
A major form of post-translational modification
digestive enzymes require this
activate protein
Proteolytic cleavage
process in brief and the purpose of this
occurs when a protein cleaves one or more bonds in a target protein to activate, inhibit or destroy the protein’s activity
cleaves- cuts out
RER
definition
- Rough endoplasmic reticulum
- organelle made up of membranes with ribosomes attached
Signal sequence
a short stretch of amino acids at one end of the polypeptide that determines its eventual location in the cell
SER
what it stands for and definition
- Smooth endoplasmic reticulum
- an organelle found in most eukaryotic cells
what does SER produce compared to RER
SER- lipids, steroid hormones
RER- proteins
vesicles
definition
small membrane bound compartments filled with liquid
microtubules
definition
a network of tubes where vesicles move across the cell
cytosolic proteins
definition
finish translation in cytosol and stay there to synthesise proteins
carry a signal sequence that directs them to the correct location inthe cell
cytosolic proteins
examples
enzymes of glycolisis
enzymes that attach amino acids to tRNA molecules for use in protein synthesis