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General IBS Quiz

Question 1 of 53

1

What is the enzyme that catalyses the reversible reaction that converts Glucose-6-Phosphate to Fructose-6-Phosphate?

Select one of the following:

  • Phosphofructokinase

  • Phosphoglucose isomerase

  • Aldolase

  • Glyceraldehyde-3-phosphate

Explanation

Question 2 of 53

1

What is the function of exonuclease?

Select one of the following:

  • Removal of RNA primers

  • Removal of DNA primers

  • Stitching together of Okazaki fragments

  • Joining adjacent nucleotides together

Explanation

Question 3 of 53

1

What direction does the coding strand run in?

Select one of the following:

  • 5' to 3'

  • 3' to 5'

Explanation

Question 4 of 53

1

What direction does the template strand run in?

Select one of the following:

  • 3' to 5'

  • 5' to 3'

Explanation

Question 5 of 53

1

What is the function of Gyrase?

Select one of the following:

  • Prevent DNA supercoiling

  • Add DNA sequence repeats to the 3' end of DNA strands at the end of chromosomes

  • Unwind the DNA strand

  • Remove RNA primers

Explanation

Question 6 of 53

1

RNA contains the bases Adenine, Thymine, Cytosine and Guanine.

Select one of the following:

  • True
  • False

Explanation

Question 7 of 53

1

snRNA forms part of a complex with proteins (snRNPs) which aid in the formation of the spliceosome that is involved in pre-mRNA splicing.

Select one of the following:

  • True
  • False

Explanation

Question 8 of 53

1

What post-transcriptional modifications are added to mRNA?

Select one or more of the following:

  • 5' methyl-guanosine cap

  • 3' poly A tail

  • 5' methyl-adenosine tail

  • 3' mono A tail

Explanation

Question 9 of 53

1

What codon signals the start of translation of a protein?

Select one of the following:

  • AUG

  • ATG

  • TAC

  • UAA

Explanation

Question 10 of 53

1

Why is the triplet code known as degenerate?

Select one of the following:

  • More than one codon codes for one amino acid

  • Codons can become mutated

  • Codons are read three bases at a time

Explanation

Question 11 of 53

1

Where does DNA replication, transcription and splicing occur?

Select one of the following:

  • Cytoplasm

  • Nucleus

  • Mitochondria

  • Extracellular Matrix

Explanation

Question 12 of 53

1

An open reading frame is a section of RNA with a small number of codons that results in a truncated, non-functional protein.

Select one of the following:

  • True
  • False

Explanation

Question 13 of 53

1

What is the enzyme responsible for charging tRNA with amino acids?

Select one of the following:

  • Amino-acyl tRNA synthetase

  • Peptidyl Transferase

  • Signal Peptidase

  • Phosphotransferase

Explanation

Question 14 of 53

1

Most mutations are only detrimental to a protein if they occur in the exons; the coding regions of DNA.

Select one of the following:

  • True
  • False

Explanation

Question 15 of 53

1

Phospholipids are amphipathic molecules, what does this mean?

Select one of the following:

  • They possess two properties in a single structure

  • They can form bilayer sheets

  • They are highly hydrophobic molecules

  • They can form micelle structures

Explanation

Question 16 of 53

1

Phase transition occurs at a lower temperature in plasma membranes that have shorter, more unsaturated fatty acid tails.

Select one of the following:

  • True
  • False

Explanation

Question 17 of 53

1

Where does phospholipid synthesis occur?

Select one of the following:

  • Outer cytosolic leaflet of the endoplasmic reticulum

  • Outer cytosolic leaflet of the golgi apparatus

  • Inner cytosolic leaflet of the golgi apparatus

  • Inner cytosolic leaflet of the endoplasmic reticulum

Explanation

Question 18 of 53

1

What is the function of scramblase in the formation of new plasma membrane?

Select one of the following:

  • Catalysing the 'flip-flop' mechanism that distributes phospholipids between the outer cytosolic and inner cytosolic portions of the plasma membrane

  • Catalysing the fusion of the newly synthesised portion of the plasma membrane to the existing plasma membrane

  • Catalysing vesicle release from the endoplasmic reticulum after the newly synthesised portion of the plasma membrane is produced

Explanation

Question 19 of 53

1

What are the three subtypes of phospholipid?

Select one or more of the following:

  • Phosphotidylcholine

  • Phosphotidylethanolamine

  • Phosphotidylserine

  • Phosphotidylvaline

  • Phosphotidylethylamine

  • Phosphotidyladenosine

Explanation

Question 20 of 53

1

The function of the enzyme Flippase is to aid fusion of the newly synthesised plasma membrane with the current plasma membrane.

Select one of the following:

  • True
  • False

Explanation

Question 21 of 53

1

Glycosylation is the process by which a triglyceride side chain is added to a protein, such as when glycoproteins are made in the endoplasmic reticulum.

Select one of the following:

  • True
  • False

Explanation

Question 22 of 53

1

Transmembrane proteins contain which of the following components that enable them to become embedded in membranes?

Select one or more of the following:

  • Signal sequence

  • Stop-transfer sequence

  • Embed sequence

  • Translocate sequence

Explanation

Question 23 of 53

1

Recognition of the stop-transfer sequence in a transmembrane protein causes what to happen?

Select one of the following:

  • The transmembrane protein to travel across the membrane

  • The transmembrane protein to become embedded in the membrane

  • The transmembrane protein to be removed by enzymatic digestion

Explanation

Question 24 of 53

1

Steroid and Thyroid hormones can travel across the plasma membrane and the nuclear membrane due to what property?

Select one of the following:

  • Lipophilic

  • Hydrophilic

Explanation

Question 25 of 53

1

Lipophilic hormones such as Testosterone (steroid hormone) can only exhibit its function if :

Select one of the following:

  • A special transporter protein that enables testosterone transport across the membrane is present

  • The receptor that testosterone binds to in order to act as a transcriptional factor is not faulty

  • The enzyme that catalyses testosterone transport is not denatured

Explanation

Question 26 of 53

1

Due to adrenaline's lipophobic nature, how can it cause intracellular effects?

Select one of the following:

  • It acts on a receptor on the external cell surface, causing the alpha sub-unit of the heterotrimeric complex to activate and go on to activate adenylyl cyclase. This enzyme produces cAMP that participates in further cascade reactions in order to produce adrenalines required effect - glucose release.

  • A special accomodating channel protein (AACT) allows adrenaline and other catecholamines to be transported across lipophilic membranes and produce their effects intracellularly, without altering osmolarity.

Explanation

Question 27 of 53

1

Wnt is another lipophobic hormone. It activates the destruction complex which destroys beta-catenin and then allows activation of transcriptional factors to promote transcription.

Select one of the following:

  • True
  • False

Explanation

Question 28 of 53

1

How many layers does pseudostratified epithelium contain?

Select one of the following:

  • 1

  • 2

  • 3

Explanation

Question 29 of 53

1

What is the appearance of stratified columnar epithelium?

Select one or more of the following:

  • One layer thick

  • Multiple layers thick

  • Equally wide and long, cuboidal in shape

  • Long, thin, column arrangement in shape

Explanation

Question 30 of 53

1

What is the barrier and fence function?

Select one of the following:

  • The prevention of paracellular movement of molecules due to tight junctions between cells

  • The prevent of diffusion of molecules across the plasma membrane, without a facilitating channel protein

  • The way in which lateral surface modules (such as desmosomes) anchor adjacent cells together

Explanation

Question 31 of 53

1

Adherens junctions contain actin filaments.

Select one of the following:

  • True
  • False

Explanation

Question 32 of 53

1

Desomosomes contain tubulin microtubules.

Select one of the following:

  • True
  • False

Explanation

Question 33 of 53

1

Collagen formation occurs in what order?

Select one of the following:

  • Protocollagen -> Tropocollagen -> Collagen fibre assembly

  • Tropocollagen -> Protocollagen -> Collagen fibre assembly

  • Collagen fibre assembly -> Tropocollagen -> Protocollagen

  • Collagen fibre assembly -> Protocollagen -> Tropocollagen

Explanation

Question 34 of 53

1

Intermediate filaments are cell specific.

Select one of the following:

  • True
  • False

Explanation

Question 35 of 53

1

What are the layers of the epidermis in descending order?

Select one of the following:

  • Stratum Corneum -> Granular layer -> Spinus layer -> Basal layer

  • Granular layer -> Spinus layer -> Basal layer -> Stratum Corneum

  • Spinus layer -> Basal layer -> Granular layer -> Stratum Corneum

  • Granular layer -> Stratum Corneum -> Basal layer -> Spinus layer

Explanation

Question 36 of 53

1

Where is more K5/K14 found?

Select one of the following:

  • Apical layer

  • Basal layer

Explanation

Question 37 of 53

1

Where is more K1/K10 found?

Select one of the following:

  • Apical layer

  • Basal layer

Explanation

Question 38 of 53

1

Keratin genes are differentially expressed in the different epidermal layers, producing dominant subtypes in different epidermal layers

Select one of the following:

  • True
  • False

Explanation

Question 39 of 53

1

What are the components of a desmosome?

Select one or more of the following:

  • Desmogleins

  • Desmocollins

  • Plakoglobin

  • Plakophilin

  • Plakotrypsin

  • Desmoglobulin

  • Desmochitin

Explanation

Question 40 of 53

1

What is a hemidesmosome?

Select one of the following:

  • A basal cell-cell adhesion module that can interact with the ECM of the basement membrane

  • A lateral cell-cell adhesion module that permits electrical communication between cells

  • A lateral cell-cell adhesion module that anchors adjacent cells together

Explanation

Question 41 of 53

1

Pemphigus Foliaceus affects what epidermal layer?

Select one of the following:

  • Upper

  • Lower

Explanation

Question 42 of 53

1

Epidermolysis bullosa affects what cell-cell adhesion module?

Select one of the following:

  • Desmosomes

  • Hemi-desmosomes

  • Tight junctions

  • Adherens junctions

Explanation

Question 43 of 53

1

What are types of epidermolysis bullosa?

Select one or more of the following:

  • EB Simplex

  • EB Junctional

  • EB Dystrophic

  • EB Vulgaris

  • EB Foliaceus

  • EB Desmosomal

Explanation

Question 44 of 53

1

Why is Tubulin known as "dynamically unstable"?

Select one of the following:

  • It is continually assembled and disassembled at its plus end

  • It cannot be stored in cells as it is unstable

  • Tubulin is composed of more than one sub-units

Explanation

Question 45 of 53

1

Actin's structure shows a twisting pattern due to the + and - charges on G-actin during polymerisation

Select one of the following:

  • True
  • False

Explanation

Question 46 of 53

1

Mutations in intermediate filaments are more detrimental to cells than mutations in actin filaments or tubulin microtubules

Select one of the following:

  • True
  • False

Explanation

Question 47 of 53

1

What is meant by actin cycling?

Select one of the following:

  • The disassembly of actin filaments, diffusion and subsequent reassembly close to a stimulus site

  • The way actin polymerises into F-actin

Explanation

Question 48 of 53

1

Which of the following protein translocations into organelles are unidirectional?

Select one or more of the following:

  • Nucleus translocation

  • Mitochondria translocation

  • Peroxisomal translocation

Explanation

Question 49 of 53

1

Mutations in peroxisomes are not always fatal because peroxisomes are cell specific.

Select one of the following:

  • True
  • False

Explanation

Question 50 of 53

1

Which of the following are ER modifications of proteins?

Select one or more of the following:

  • N-linked glycosylation

  • Completion of translation

  • Folding of proteins

  • Formation of disulphide bonds

  • Modification of N-linked oligosaccharide side chains

  • Oxygen-linked glycosylation

  • Mannose-6-phosphate modification

  • Sorting to final destinations

Explanation

Question 51 of 53

1

Which of the following are Golgi modifications of proteins?

Select one or more of the following:

  • Nitrogen-linked glycosylation

  • Completion of translation

  • Folding of proteins

  • Formation of disulphide bonds

  • Modification of N-linked oligosaccharide side chains

  • Oxygen-linked glycosylation

  • Mannose-6-phosphate modification

  • Sorting to final destinations

Explanation

Question 52 of 53

1

What is direct sorting in the golgi network?

Select one of the following:

  • Vesicles travelling straight to the membrane from the golgi apparatus

  • Vesicles travelling from the golgi to the wrong domain and then being retrieved by early endosomes and being sent to the correct domain such as the membrane

Explanation

Question 53 of 53

1

What is indirect sorting in the golgi network?

Select one of the following:

  • Vesicles travelling from the golgi to the wrong domain and then being retrieved by early endosomes and being sent to the correct domain such as the membrane

  • Vesicles travelling straight to the membrane from the golgi apparatus

Explanation