2A Flashcards
protein structure and function
Protein/polypeptide
diverse group of moleculesMade of monomers of amino acids bound together via peptide bonds and has several structural and functional properties like hair and bodily processes.
what is DNA made of
Dna contains a phosphate gorup, a 5 carbon pentose sugar and a nitrogenous base.
What nitrogenous bases are complementary in DNA
Adenine & Thymine
Cytosine and Guanine
What nitrogenous bases are complementary in RNA
Adenine binds with Uracil
Cytosine pairs with guanine
DNA codes for a certain type of protein to made through what processes
Transcription
Translation
Transcription
involves the copying of DNA stand into an mRNA strand
Translation
involves the reading mRNA strand to produce a polypeptide chain of amino acids in the ribosomes
Proteome
completeset of proteins in acell
Proteomics
the study of the structure and function of proteins as well as the way they function and interact with eachother.
Where is proteomics used
1.medical diagnosis
2. producing monoclonal antibodies to treat cancer and viruses
3. design drugs to produce various conditions
how proteins are so diverse/the differnet proteins
- Transport proteins
2.Receptors on the plasma membrane
- enzymes as biological catalyst that speed up chemical reactions
- antibodies
- hormones
6.structural proteins like hair and nails
Transport proteins
proteins that move ions and large molcules across the plasma membrane during facicilated diffusion
Receptors
receptors are proteins that bind to specific signalling molecules, initiating a celluar response and involved in signla transudction
signal transduction
the process of celluar communcation and response to external signals.
enzymes
biological catalayst that speeds up chemcial reactions
antibodies
proteins produce by the immune system to defend against foreign pathogens
Hormones
released by the endocrine gland to signal between different cells, or cause stimulation or inhibition
Chemical structure of AMINO ACIDS
carboxyl group(COOH)
Amino group(NH2)
R group(which determine the type of amino acid )
central carbon
How many amino acidsare there and of them how many are actually essientla
20 amino acids
9 are essiental amino acids because they are not produced in the body.
What are amino acids made of
C-carbon
H-hydrogen
O-oxygen
N-nitrogen
S-sulfur
R group
a group that contains a carbon andhydrogen attom attached to a moleucle and determines the type of amino acid
what forms the primary structure of a protein
polypeptide chain
Condensation polymerisation reaction
a chemical process where smaller molecules combine to form larger molecules, releasing a smaller molecule such as water in the process.
What are the 4 levels of protein stuctures
- primary
2.secondary
3.tertiary - quaternary
What is a primary structure and when is it formed
a polypeptide chain of amino acids help together via peptide bonds
Primary structures is formed when amino acids are joined together through a condensation reaction and produced in SOME ribosomes through translation.
Secondayr structure
formed when a polypeptide chain folds and coils forming hydrogen bonds between amino acids which forms an alpha helices and beta pleated sheet
Tertiary structure
, refers to the 3D shape of a protein and is formed when secondary structures further fold by forming interactions and bonds between amino acids and the R group.Functions to determine the proteins shape and functiinalcapabitlies
Types of interactions of the tertiary structures
disulfide bond(strong)
weak hydrogen or ionic bonds
hydrophobic interactions
Quaternary structure
is formed when two or more polypeptide chains with tertiary structures join together.
functions to enhance proteins functionla capabilties
and not all proteins will have quantatary structures
what are possible Changes to protein structures
- proteins can folded, based on the sequence of the amino acids in a primary structure is dependen
- one chnage in an amino acid will form a different protein OR the amino acid may no longer be functional due to that change
- Proteins can bestructure via denaturation when exposed to high temperatures or extreme PH levels
Unfolding of protein structures results in
a loss of function and is irreversible
what is a hormone and examples
released by the endocrine gland to signal between different cells, or cause stimulation or inhibition
Insulin is a hormone that maintains glucose levels by allowing glucose to enter the cell
what the elements make up the proteins of the amino acid
CHON=
carbon, hydrogen, oxygen and nitrogen
why are essiental amino acids knwon as essiental amino acids
they are known as essential amino acids because their not sythensised by the body, and therefore it is essential for these amino acids to consumed through ones diet.
what is the signifance of an R group- 2 marks
R group provides the amino acid with its own identity
and the R group provides the amino acid its own chemical properties which determines how the amino acid will react with the eachother and the surrounding environments, and therefore this will determine their specific function.
proteins have R groups that can be hydrophilic or hydrophobic.
eg Alenine is an amino acidwith a hydrophbic R group, whilst tryosine has an hydrophilic R group
which is more advantageous
tyrosine which has an hydrophilic R group is more advantageous because it can travel through the body to carry out bodily processes as 60% of the body is composed of water n it repels water.
what happens to an hydrophobic R group of amino acid in the body.
hydrophobic molecules of the R group are carried by lipophobic or hydrophilic molecules through the bloodstream
hydrogen can only bond with…. nitrogen can only bond with… oxygen cna only bondwith… and carbon can only bond with
hydrogen can only bond with one element at once
nitrogen can only bond with 3 elements at once
oxygen can only bond with 2 elements at once
carbon can only bond with 4 elements at one.
beable to draw peptide bond
when/how is a peptide bond formed
a peptide bond is formed between two amino acids.
wehen the bonds between amiino acid is broken down the reaction is knwon as the
hydrolysis reaction
how beta pleatedsheets and alpha sheets created
secondary structures LIKE alpha helicies and beata sheets are formed when the hydrogen of the amino group of one amino acid and the oxygen of the caboxyl group of another amino acid join together to create a hydrogen bond which is the flattened folding for beta sheets nad tight coils for alpha sheets.
which sturcutres have functions and what arethose functions
Primary structures have NO FUNCTION
secondary structures have NO FUNCTION
tertiary structures have FUNCTIONwhich is to determinign the proteins shape and its functional capabilties.
quaternary have FUNCTION of enhancing the functional capabilties of the protein complex like enzyme catalasis
a minium strucutre that a protein needs to be at to function
is the tertiary structure.
examples of each type of structure
primary structure; peptide bonds
secondary: alpha helix and beat pleated sheets
tertiary: hydrogen bonds between the R groups, ionic bonds, ionic bonds, disulfide bridges, and hydrophobic interactions
quanternarystructure;haemoglobin
an example of a quaternary structure
an example of quaternary is hemoglobin which contains 4 polypeptide chains and contains a prosthetic group of haem which contains an iron ion –> function: carry O2
must be able to label structure of cell and organelles function
what is the folding of a protein dependent on
the folding of the proteins is dependent on the sequence of amino acids in a primary structure
when are proteins denatured
high temperatures or extreme high or low PH levels
hydrolysis reaction
wehen the bonds between amiino acid is broken down the reaction
function of RNA vs DNA
The function of DNA is to store genetic information for the long term, whilst the function of RNA is to to transfer genetic information.
