Gene Expression Flashcards
What do the proteins produced do?
All work together to determine the characteristics that are typical for a species
What type of cell expresses two types of gene?
A specialised cell
What are the 2 types of gene expressed by a specialised cell?
Those that are vital for its maintenance ( like genes coding for respiratory enzymes) and ones that are vital for its specialised function ( like genes coding for the slow and fast twitch muscle fibres
What is RNA?
A single stranded molecule made of nucleotide sub units
In RNA what does each sub unit consist of?
A phosphate group, a base and a ribose sugar
What are the bases in RNA?
Cytosine
Uracil
Guanine
Adenine
What types of RNA are there?
mRNA
tRNA
rRNA
When is mRNA formed and what is its function?
Formed during the transcription of the DNA in the nucleus
Iris the template for protein synthesis at the ribosomes and it dictates the sequence of amino acids in the protein being synthesised
Describe mRNA
The sugar used is ribose
The bases are adenine cytosine guanine and URACIL
It only has one strand
It moves from the nucleus to the cytoplasm
What is the function of tRNA?
It carries specific amino acids to the ribosomes for translation of the genetic code
What is the function of rRNA?
It binds proteins to ribosomes
Describe a ribosome
Composed of 2 sub units, a small one and a large one
It’s the site of protein synthesis
The small sub unit reads the code on mRNA
Large sub unit provides active sites
What determines the phenotype of an organism?
Gene expression
