1.2: Proteins

Question 1

The entire set of proteins expressed by the genome of an organism.

Answer 1

Proteome

Question 2

Process that results in many different proteins being synthesised from each gene which may explain why the proteins is much larger than the genome.

Answer 2

Alternative RNA splicing

Question 3

Various exons of a gene may be included or excluded from the final. mature mRNA.

Answer 3

Alternative RNA splicing

Question 4

Coding DNA and RNA
AND
Non-coding DNA and RNA.

Answer 4

Exon
AND
Intron

Question 5

Products of non-coding RNA genes.

Answer 5

Transfer RNA (tRNA) or Ribosomal RNA (rRNA) or RNA that controls expression of other genes

Question 6

Internal and external factors
that affect the set of proteins
size on the surface area to
expressed by a cell.

Answer 6

Metabolic activity OR Cellular stress OR Signalling molecules OR Disease

Question 7

Affect of an increase in cell size on the surface area to volume ratio.

Answer 7

Decreases

Question 8

Network of tubules continuous with the nuclear membrane involved in lipid and protein synthesis.

Answer 8

Endoplasmic reticulum or ER

Question 9

The sequence in which the amino acids are synthesised into the polypeptide.

Answer 9

Primary protein structure

Question 10

Series of flattened membrane discs involved in protein modification and secretion.

Answer 10

Golgi apparatus

Question 11

Vesicles containing hydrolase
enzymes used to digest worn
out organelles and invading
micro-organisms.

Answer 11

Lysosomes

Question 12

Membrane containers that transport materials around the cell using protein motors and microtubules.

Answer 12

Vesicles

Question 13

Protein fibres that carry vesicles to the correct destination.

Answer 13

Microtubules

Question 14

Organelle that synthesises lipids such as phospholipids.

Answer 14

Smooth Endoplasmic reticulum or SER

Question 15

Translates mRNA to produce proteins.

Answer 15

Ribosomes

Question 16

Part of cell all proteins start to be translated by ribosomes.

Answer 16

Cytosol

Question 17

Short stretch of amino acids at the start of a protein that determines the eventual site for complete translation.

Answer 17

Signal sequence

Question 18

Two parts of a cell involved in the complete synthesises of a transmembrane protein.

Answer 18

Cytosol and Rough ER

Question 19

Part of RER in which the translation of transmembrane proteins are completed.

Answer 19

Membrane

Question 20

Part of RER in which the translation of proteins to be secreted are completed.

Answer 20

Lumen

Question 21

Examples of secreted proteins

Answer 21

Peptide hormones OR Digestive enzymes

Question 22

Process in which sugars are added to proteins as they pass though the Golgi apparatus.

Answer 22

Post-translational modification

Question 23

Term for a short section of an inactive precursor enzyme being cut out to activate once secreted into the digestive system.

Answer 23

Proteolytic cleavage

Question 24

Structural changes which may result in several different forms of the same protein.

Answer 24

Post-translational modification

Question 25

Change in the shape of a protein which usually results in a change in function or activity.

Answer 25

Conformation change

Question 26

Polymer composed of many amino acid monomers

Answer 26

Protein

Question 27

Describes the structure and function of a protein.

Answer 27

Sequence of amino acid’s

Question 28

Covalent bond joining amino acids in a polypeptide.

Answer 28

Peptide bond

Question 29

The sequence in which the amino acids are synthesised into the polypeptide.

Answer 29

Peptide bond

Question 30

Bonds that hold the secondary protein structure together.

Answer 30

Hydrogen

Question 31

The sequence in which the amino acids are synthesised into the polypeptide.

Answer 31

Primary protein structure

Question 32

Types of secondary protein structures.

Answer 32

Alpha helixes AND Parallel / anti-parallel beta pleated sheets AND Turns.

Question 33

Classes of amino acid R groups.

Answer 33

Basic (positively charged), Acidic (negatively charged), Polar and Hydrophobic.

Question 34

Level of protein structure which is folded and held together by various bonds and interactions between the R groups.

Answer 34

Tertiary

Question 35

Types of bonds and interactions that hold a folded tertiary protein structure together

Answer 35

Ionic bonds, hydrogen bonds, ldfs, disulphide bridges or hydrophobic interactions.

Question 36

A non-protein unit which is tightly bound to a protein and is necessary for its function.

Answer 36

Prosthetic group.

Question 37

What level of protein structure is haemoglobin? It is also the protein structure of an allosteric protein that consists of four subunits.

Answer 37

Quaternary structure

Question 38

Factors influencing interactions between R groups.

Answer 38

Temperature and pH

Question 39

Substance that can bind to the protein R groups which are not involved in protein folding.

Answer 39

Ligand

Question 40

Region of protein with complementary shape and chemistry to a ligand.

Answer 40

Binding site

Question 41

Consequence of the conformation change once a ligand binds to a protein.

Answer 41

Change of function OR protein activated OR protein deactivated

Question 42

Proteins that have at least two active sites which are spatially separate.

Answer 42

Allosteric

Question 43

Term for changes in binding at one subunit alters the affinity of the remaining subunits in allosteric proteins.

Answer 43

Co-operativity

Question 44

Name for the second binding site on allosteric enzymes.

Answer 44

Allosteric or secondary

Question 45

Name for molecules that regulate the activity of an enzyme when they bind to an allosteric site.

Answer 45

Modulators

Question 46

Ligand that binds to a secondary allosteric binding Site increasing the affinity of the enzyme for the substrate.

Answer 46

Positive modulator

Question 47

Ligand that binds to a secondary allosteric binding site decreasing the activity of the enzyme.

Answer 47

Negative modulator

Question 48

Term for the strength of attraction between a protein and its ligand.

Answer 48

Affinity

Question 49

Quaternary protein found in red blood cells which shows co-operativity in the binding of oxygen.

Answer 49

Haemoglobin

Question 50

Affect of the first oxygen binding to a haemoglobin subunit on the affinity to the second due to co-operativity.

Answer 50

Increased

Question 51

Factors which decrease the affinity of haemoglobin for oxygen. Causes a right shift in oxygen dissociation curves.

Answer 51

Increased temperature AND decreased pH

Question 52

Form of post translational modification where a phosphate group is added to a protein, resulting in a reversible conformation change.

Answer 52

Phosphorylation

Question 53

Enzyme which adds a phosphate group to protein molecules (phosphorylation).

Answer 53

Protein kinase

Question 54

Source of the phosphate protein kinase adds to proteins.

Answer 54

ATP

Question 55

Enzyme which removes a phosphate group from protein molecules (dephosphorylation).

Answer 55

Protein phosphorylase

Question 56

Affect of phosphorylation on proteins.

Answer 56

Change in conformation or activity.

Question 57

Examples of cellular proteins who activity is regulated by phosphorylation or dephosphorylation.

Answer 57

Enzymes or receptors.

Question 58

Charges added to protein by phosphorylation.

Answer 58

Negative