Protein Synthesis Flashcards
Define nucleic acids
Macromolecules that are involved in inherited information.
What is he condensation reaction
When two Amino acids are joined to form a dipeptide. It releases water molecule.
What is the hydrolysis reaction
When a dipeptide is split because water is added. This occurs in digestion
What is a peptide bond
When a hydrogen bond occurs
Define nucleic acids
Biochemical macromolecules that are involved in the transmission of inherited information
What doesDNA and RNA stand for (spelling must be right)
Deoxyribonucleic acid (DNA) Ribonucleic acid (RNA)
Nucleic acids are polymers what does this mean
They are made up of monemers called nucleotides
What are the four bases in DNA nucleotides
Adenine
Guanine
Thymine
Cytosine
What is the complementary base pair rule
Adenine to thymine
Guanine to cytosine
Which part of DNA has strong bonds and which have weak
Weak hydrogen bonds between the bases
Strong hydrogen bonds between phosphate and sugar
What’s some differences between RNA and DNA
RNA is single stranded DNA is double stranded
RNA contains the base uracil rather then thymine in DNA
DNA contains deoxyribose sugar RNA has ribose sugar
DNA is longer
All proteins are made up of monomers called
Amino acids
What’s the different between plants and animals with amino acids
Plants can manufacture all the amino acids they require
Animals must obtain a certain number of essential amino acids from their diet.
What is the structure of an amino acid and picture
Picture
What changes in each amino acid to make them difference
The R group
What is a purine
Larger bases they have two rings
Eg adenine and guanine
What is a pyrimidines
Smaller bases have one ring eg cytosine and thymine
Define anti parallel
DNA chains run in opposite directions
What does the complementary base pairing gaurantee
That new pieces of DNA are identical to the original
What are the four types of protien structure
Primary protein structure
Secondary protein structure
Tertiary protein structure
Quaternary protein structure
What is primary protein structure
A single chain of amino acids known as a polypeptide chain
What is a secondary protein structure. And the two types
The way in which the polypeptide chain is folded or coiled. Contains hydrogen bonds Alpha helix-spiral
Beta pleated- zig zag shape
What is a tertiary protein structure and example
When the protien has become 3D and has stronger bonds. It is a mixture of different types of secondary protein structures
Eg enzymes
What is quaternary protein structure
When several different polypeptide chains are attached to eachother
What determines how a polypeptide chain will fold up and determines the shape of the protein
The specific order of amino acids
Define gene
The section of DNA that controls the sequence of amino acids of a specific protein or peptide
What is the first step of gene expression called and define it
Transcription the process of copying DNA into messenger RNA. only occurs in the nucleus
What are the steps of transcription
- The double strand of DNA unwinds
- Complementary nucleotides are brought into place by RNA polymerase and placed on RNA chain.
- Pre mRNA is modified (cap and poly A tail is added introns are removed)
- Mature RNA travels out of the nucleus through a pore into the cytoplasm
Explain how pre mRNA is modified
A cap is added on the 5’ end, this protects it from enzymes
A poly-A tail is added at the 3’ end to show where the rna stops
Splicing-introns (interrupt) therefore they are cut out
-exon (excellent) therefore stay and all put together
What are introns
Introns (interrupt) a repeating bases that don’t code together
Define translation
The process of building a polypeptide chain from amino acids, guided by the sequence of codons on mRNA
The steps of translation
- Initiation- mRNA connects with ribosome.
- the first codon which codes for MET is the starting primer - Elongation- mRNA is read and tRNA brings amino acids that match with RNA codons.
- the amino attaches from the tRNA and forms a polypeptide chain. The empty tRNA is released and goes back to find more amino acids. - the stop codon is read(last codon on mRNA) and last amino acid is hydrolysed (no more amino acids can be added).
- released and processed in the Golgi body
- the stop codon is read(last codon on mRNA) and last amino acid is hydrolysed (no more amino acids can be added).
What is a codon
Three bases on mRNA
What is an anticodon
3 base sequence on tRNA that matches with a codon
The process of reading the codes
3’ to 5’ DNA strand
Through transcription to
mRNA strand (opposites with U instead of T)
Through translation with Anti codons on tRNA
with amino acids attached
Creating a protein from the polypeptide chain steps
- The chain is threaded through a poor in the ER membrane into the cisternal space this is where the folding of amino acids occurs
- Folded protein travels song er continuing structural changes
- At the end of the ER channel the protieons will be encased in a lipid membrane called vesicle.
The vesicle buds off the ER and moves to Golgi body.
Why does the protein from the ER become encased with a lipid memebrane called a vesicle
Therefore enzymes won’t destroy it and protects it while it goes to the Golgi apparatus for transport
What happens to the protein in the Golgi body
Vesicles travel through Golgi faces where they are modified using enzymes
The final stage of packaging involves gathering the same proteins wrapped in a vesicle for bulk transport
What’s the cis face and trans face of the Golgi body
Cis face-Receives vesicles from the er (closest to er)
Trans face-Ships off material in vesicles which pinch off from the Golgi body.
What are the two types of genes
Structural genes and regulatory genes
What is a structural gene
A gene that will be used to produce a specific protein (genes that make our body run)
What is a regulatory gene
A gene that produces protein that control the action of other genes (regulate when structural genes are turned on)
What’s the lac operon
Deals with lactose (lad stands for lactose)
Lac Z is a protein that breaks down lactose
Only needed if lactose is present inside prokaryotic cell
What occurs if no lactose is present
The repressor protein binds to the operator and the lac Z can’t be made
Diagram in photos
What happens when lactose is present in a prokaryotic cells
When lactose is present it binds repressor protein changing its shape so it releases from the operator site. EXPRESSSION ON
rna polymerase is able to form Lac Z
What is the codon on mRNA that means start and what’s the amino acid it codes for
AUG is the codon
MET is the amino acid
