ib biology 2.4 proteins Test and Flashcards

peptide bond

c-n. c of carboxyl and n of nh2

what do the polypeptides that all organisms use have in common? (hint: same buildiing blocks )

they are all made up of a combo of the same 20 amino acids. what differs is the combination

what happens in ribosomes

polypeptide synthesis

what substance tells ribosomes what polypeptide to make

messenger RNA (mRNA)

what is the primary structure for protein (1st stage of synthesis)

amino acid sequence. its the order formed by covalent peptide bonds

what is the process of DNA telling informtaion to RNA called? (DNA _____ the instructions to RNA)

transcription

what is the verb for RNA sending the instructions to the ribosome

translation

what is the genetic code?

sequence of bases on mRNA it tells the ribosome which amino acids to use in polypeptide synthesis

what are some examples of properties that amino acids can have

polar/hydrophilic, nonpolar/hydrophobic, +/- charge (ionic )some have sulfur

what do properties of amino acids/polypeptides affect?

how it folds up into a protein during the third stage

whats the alpha helix

a coiled secondary protein structure. results from a hydrogen bond every fourth amino acid

how does the secondary structure happen (how is it bonded)

hydrogen bonds between the H in NH3 and O in carboxyl

whats the beta pleated sheet

a secondary structure of protein. formed by hydrogen bonds between parallel proteins

what is tertiary structure primarily dependent on?

interactions between R groups

whats a disulfide bridge

tertiary structure. strong covalent bonds between 2 sulfur atoms (from a R group) ex is cysteine

what are ionic bonds (in proteins)

bond bw positively and negatively charged side chains

where do hydrophobic chains go in a protein relative to the other ones

inside, because it wants to get away from the water.

how do we know if something is a quaternary structure

made up of multiple polypeptide chains. the structure is dependent on interactions bw the seperate polypeptide chains

whats a conjugated protein

it functions with chemical groups that aren't polypeptides quaternary structures only

whats a example of conjugated protein

hemoglobin each polypeptide chain contains an iron containing molecule called a heme group.

shape of fibrous and globular protein

fibrous: long and narrow. globular: spherical and rounded (globe = earth = round)

what function do fibrous and globular proteins have

fibrous: structural. strength and support globular: catalyctic, transport

is fibrous proteins soluble or insoluble (generally )

insoluble globular is the opposite: soluble

is globular soluble or insoluble

soluble. globular = circular = water (like a water droplet) fibrous is the opposite: insoluble

what is a trait of the amino acid sequence of a fibrous protein

its repetitive

what is a trait of the amino acid sequence of a globular protein

the sequence is irregular. no pattern

is fibrous or globular more stable (sensitivity to heat, pH, etc.)

fibrous is more stable: less sensitive, more resistant to change

provide a few examples of fibrous proteins (dont need all, just a few)

collagen, myosin, actin, keratin, elastin

provide a few examples of globular proteins (dont need all, just a few)

catalase, haemoglobin, insulin, immunoglobin

what is a difference in where the R groups are between fibrous and globular proteins? (hint: it has to do w water)

●●In globular proteins the hydrophobic R groups are folded into the core of the molecule, away from the surrounding water molecules, this makes them soluble. In fibrous proteins the hydrophobic R groups are exposed and therefore the molecule is insoluble.

what have biotechnologically produced (made by humans) proteins allowed us to do?

•enzymes for removing stains in clothing detergent •monoclonal antibodies for pregnancy tests •insulin for treating diabetics Disease treatments

what are GMOs often used to do (in relation to proteins)

they are used to produce proteins. its a difficult and expensive process though

how do proteins help with cell adhesion?

they make adjacent animal cells stick together. ex: adherens

what are membrane transport proteins used for?

facilitated diffusion and active transport, and also for electron transport during cell respiration and photosynthesis. diffusion = spreading

which category of macromolecules (carbs, lipids, etc.) are receptors (for hormones and stuff) made up of?

proteins.

what are histones?

a type of protein Histones are associated with DNA in eukaryotes and help chromosomes to condense during mitosis. it condenses/packs the dna

what are immunoglobins

antibodies. a type of protein

whats rubisco

ribulose bisphosphate carboxylase it is an enzyme that catylzes the reaction that turns carbon dioxide into more useful stuff (like carbohydrates), (what it turns into is kinda complicated and prob doesnt matter so prob dw about specifics)

where is rubisco found in high concentrations

leaves, algal cells (in algae )

what type of cell in which part of the body is insulin secreted from

beta cells in the pancreas

what does insulin do

signal cells to open up to take in glucose. it therefore reduces concentration of glucose in blood (cus the glucose goes out of the blood, into the cell(s))

what happened to the insulin of type 1 diabetics

they dont make enough so they need to inject some synthetic insulin

whats an antigen binding site

receptor that detects molecules on a pathogen(germ) to trigger an immune response

whats rhodopsin

a pigment that absorbs light . retinal molecule absorbs a single photon of light -> changes shape -> change to the opsin -> the rod cell sends a nerve impulse to the brain. it is made from opsin (polypeptide) that surrounds a prosthetic group

what is collagen

rope-like proteins made of three polypeptides wound together and it strengthens stuff

how much of the protein of the body is collagen (fraction)

1/4th

what does collagen do (purpose)

strengthens skin + blood vessel walls (makes it resistant to tearing). prevents cracks and fractures in bones and teeth

what does the molecular structure of spider silk look like

bottom has parrallel arrays and middle is more disordered

defintion of proteome?

all protein produced by cell/tissue/organism

definitoin of genome?

all genes produced by cell/tissue/organism

what does genome determine

what proteins its possible for a organism to produce

other than genome, what affects proteome?

environment

how can we analyze a proteome

mixtures of proteins are extracted from a sample and are then separated by gel electrophoresis.

what is denaturation

disruption or breaking of bonds between proteins (especially weak ones like hydrogen bonds)

is denaturation reversible?

not usually

what are some things that can cause denaturation

extreme pH and heat

what are thermophiles

organisms (often archaea or eubacteria that live in relatively hot conditions (45 to122 °C). their proteins are stable at temperatures that are higher than normal.

Flashcards: ib biology 2.4 proteins