protien structure and function Flashcards
protein
biomacromolecule
made of amino acid chains folded
into a 3D shape
polypeptide
long chain of amino acids
Peptide hormone:
A protein signalling molecule that regulates physiology or behaviour.
Carboxyl group
the functional group on amino acid molecules that contains a hydroxyl (-OH) and an oxygen double-bonded to a carbon atom.
Amino group:
the functional group on amino acid molecules that is made up of one nitrogen and two hydrogens (NH2).
R-group:
the variable portion of an amino acid molecule. determines the identity of the amino acid.
Condensation reaction:
a reaction where two monomers join to form a larger molecule, producing water as a by-product.
Proteome:
All the proteins that are expressed by a cell or organism at a given time.
Amino Acid Structure
- each amino acid is made of a central carbon, amino group (NH2), CARBOXYL group (COOH), and r group
protien structure
Repeating units of monomers can join together through a condensation reaction to form polymers called polypeptides. This forms a peptide bond between each monomer unit of amino acids. occurs in ribosomes.
Nucleic acids
large polymers of nucleotides monomers that store genetic information n help with the synthesis of proteins
2 types of nucleic acids
Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA)
simil of dna and rna They both have the same basic structure:
A phosphate group
A five-carbon (pentose) sugar ring
A nitrogen containing base (nitrogenous base)
Their main difference
is the presence or absence of an oxygen atom at the 1 prime positon of the five-carbon sugar ring. deox = no oxy
The Protein Secretory Pathway
involves various different organelles that produce, fold, modify, and package proteins,exporting them from the cell via exocytosis.
exocytosis:
process by which contents of a vesicle are released from a cell, form of bulk transport and active transport ( requires energy)
process of exocytosis :
- vesicle containing secretoy products is transported to PM
- Membrane of vesicle fuses with PM
- secretory products are released from the cell ino extracellular env
messenger rna
mRNA:
Carries genetic information from nucleus to protein for protein synthesis
tRNA: transfer
delivers specific amino acids to the ribosomes.
ribosomal rRNA:
serves as the structural component of ribosomes within cells.
Transcription:
The process whereby a sequence of DNA is used as a template to produce a complementary sequence of mRNA
transaltion
The process where an mRNA sequence is read to produce a corresponding amino acid sequence to build a polypeptide
dna structure
two polynucleotide chains which run antiparallel to each other
The nucleotides from each chain forms a hydrogen bond CG AT
DNA forms
a double helix which coils around histone proteins
pre mRNA TO mRNA TRANSCRIPTOIN
- initation:transcriptiors factors bind to promotor region to intiate, RNA polymerase binds to promotor region and signals weak hydrogen bonds in dna to break
- polymares moves along dna template strand, adding rna nucleotides to growing mRNA strand
- reaches end
TRANSLATION
- intiation: mRNA molecule binds to ribosome and is read til a start codon is recognised (aug)
- elongationmRNA molecule is fed through the ribosome so next codon can be matched to its complimentory tRNA
- stop codon signifies for termination
