MMED1008 End of Semester Quiz Revision

Prokaryotes have this feature in common with eukaryotes:

1) A rigid cell wall

2) Lysosomes

3) A lipid monolayer forming the plasma membrane

4) DNA in the form of a double stranded helix

5) Mitochondria

4) DNA in the form of a double stranded helix

Which among the following statements is most correct about mitochondria?

1) Mitochondria are responsible for producing energy in the form of GTP

2) The inner membrane of the mitochondria is folded to decrease its surface area

3) Mitochondria are always found as short oval-shaped organelles

4) Mitochondria have one lipid bilayer membrane

5) Mitochondria are able to synthesise proteins for themselves

5) Mitochondria are able to synthesise proteins for themselves

At which point in the process of gene expression (transcription or translation) is a stop codon recognised?

1) At the first amino acid, signalling the start of translation

2) At the promoter, signalling the start of transcription

3) After the last amino acid, signalling the end of translation

4) After the last amino acid, signalling the end of transcription

5) At the termination signal, signalling the end of translation

3) After the last amino acid, signalling the end of translation

Which of the following statements best expresses basic cell theory?

1) All living organisms grow by generating more cells via cell division

2) Everything that we see around us is made out of cells if you look closely enough

3) Cells originate from the action of lightning on basic chemicals in the primordial soup

4) Animals primarily grow by increasing the size of their cells

5) New cells are mainly generated when two pre-existing cells come together

1) All living organisms grow by generating more cells via cell division

Which of the following is NOT a feature found in eukaryotic cells?

1) A two-layered membrane around the nucleus

2) Chloroplasts

3) A rigid cell wall

4) Circular double stranded DNA

5) Peroxisomes

4) Circular double stranded DNA

What is the main advantage of electron microscopy over regular light microscopy?

1) You get less background noise in images

2) You get better resolution

3) You get intensification of fluorescent signals (more gain)

4) You get better sensitivity to faint fluorescent signals

5) You get better contrast and a more 3D image

5) You get better contrast and a more 3D image

What is the benefit gained by using Nomarski (DIC) optics?

1) You get less background noise in images

2) You get better resolution

3) You get intensification of fluorescent signals (more gain)

4) You get better sensitivity to faint fluorescent signals

5) You get better contrast and a more 3D image

5) You get better contrast and a more 3D image

What is the main benefit of using GFP in microscopy?

1) It makes it possible to visualise otherwise invisible molecules in patient samples

2) It allows otherwise invisible molecules to be localised and quantitated in live cells

3) It allows otherwise invisible molecules to be localised and quantitated in live cells

4) It allows us to capture images in colour

5) There is no significant optical benefit, it just looks cool

6) It allows us to get better optical resolution

2) It allows otherwise invisible molecules to be localised and quantitated in live cells

Which of the following is most correct?

1) All cells are less than 1cm long

2) Living creatures are built exclusively out of cells

3) Phase contrast microscopy allows us to see chromosomes

4) People who catch Covid lose their sense of smell

5) DNA in cells is always found inside a nucleus

3) Phase contrast microscopy allows us to see chromosomes

Which among the following statements is wrong about the Golgi Apparatus?

1) It is a protein-sorting station for the delivery to many cellular destinations

2) Proteins are modified there by glycosylation (addition of long chain sugars)

3) It is involved in secretion to the cell exterior

4) It disassembles during cell division

5) It is coupled to ribosomes for translation of mRNA into protein

5) It is coupled to ribosomes for translation of mRNA into protein

Which of the following is responsible for storing and transmitting genetic information to the next generation?

1) Nucleoplasm

2) Nuclear envelope

3) Nuclear pores

4) Nucleolus

5) Chromatin

5) Chromatin

Which statement about the rough endoplasmic reticulum (RER) is most correct?

1) A fraction of a cell's energy, in the form of ATP, is produced here

2) Proteins are synthesised in the RER

3) The RER is the main site for calcium storage

4) The RER is the main site for lipid metabolism

5) All cellular proteins are synthesised in the RER

2) Proteins are synthesised in the RER

Which of the following statements is not correct:

1) Functional compartmentalisation of DNA within the nucleus can affect gene expression

2) A selective permeability membrane separates the cytoplasm and the nucleus

3) The nucleus houses all of an organism's genetic material

4) Ribosomal rRNA is synthesised in the nucleolus

5) The nuclear pores permit bi-directional transport

3) The nucleus houses all of an organism's genetic material

The Golgi apparatus is required for:

1) Conversion of light energy into chemical energy

2) Modification of proteins for transport

3) Synthesis and processing of hormones.

4) Storing and releasing water and nutrients

5) Break down of long-chain fatty acids

2) Modification of proteins for transport

Which of the following statements is true about Nucleosomes?

1) Nucleosomes can be dynamically modified, allowing for gene activation

2) The core component of nucleosomes are ribosomes

3) DNA is made out of nucleosomes

4) They are Protein/RNA complexes found in the nucleus

5) They assist with RNA folding.

1) Nucleosomes can be dynamically modified, allowing for gene activation

What is the role of the endocytic pathway in protein trafficking?

1) Delivers extracellular proteins into the cell for degradation or recycling

2) Regulates protein synthesis in the nucleus

3) Facilitates protein folding and modification in the cytoplasm

4) Transports proteins from the Golgi apparatus to the cell membrane

5) Transports proteins from the ER to the Golgi apparatus

1) Delivers extracellular proteins into the cell for degradation or recycling

Which of the following vesicle-coating complexes is mainly involved in directionality during protein trafficking

1) V-Snares

2) Golgins

3) COPII

4) T-snares

5) VamP

3) COPII

Which of the following is true regarding mitochondrial DNA?

1) It can be seen in a karyotype

2) It sits inside the nucleus

3) It does not code for genes

4) It is approximately the same size as the nuclear genome

5) It does not get compacted at metaphase

5) It does not get compacted at metaphase

How is the q arm defined on a chromosome?

1) The shorter arm

2) The longer arm

3) The arm that is closer to the top of the slide

4) The arm with less G banding

5) The arm with more genes

2) The longer arm

The basic unit of DNA is known as a:

1) Nucleolus

2) Nucleus base

3) Nitrogenous base

4) Nucleoside

5) Nucleotide

5) Nucleotide

What gives DNA its directionality?

1) The double helix structure

2) The hydrogen bonds between the bases

3) The structure of the carbons in the sugar

4) The sequence of the genes

5) The order of the bases (A, G, C and T)

3) The structure of the carbons in the sugar

Regarding the human genome, which of the following statements is INCORRECT?

1) Approximately 20% of the human genome codes for genes

2) The human genome is considerably more variable than we had anticipated

3) Information gained from the human genome sequence is revolutionising medicine

4) Technology advances have significantly contributed to our ability to sequence the human genome

5) There is no such thing as the perfect human genome

1) Approximately 20% of the human genome codes for genes

Regarding DNA and RNA base pairing, which of the following is CORRECT?

1) Uracil cannot base pair with DNA

2) RNA can only base pair with RNA

3) RNA can only base pair with DNA

4) DNA can only base pair with DNA

5) DNA can base pair with both DNA and RNA

5) DNA can base pair with both DNA and RNA

With respect to open reading frames of an mRNA, which of the following statements are CORRECT?

1) The entire open reading frame is usually contained within the first exon

2) All 3 open reading frames will translate into a functional protein

3) Only 1 open reading frame will contain a stop codon

4) Only 1 reading frame will be translated into the correct protein sequence

5) All 3 open reading frames will be translated from every mRNA

4) Only 1 reading frame will be translated into the correct protein sequence

Prokaryotes differ from eukaryotes because:

1) They have a lipid bilayer forming a plasma membrane

2) They have DNA in the form of a double stranded helix

3) They contain no membrane bound organelles

4) They have a cell wall

5) They are typically significantly larger and simpler

3) They contain no membrane bound organelles

A human baby normally doubles their weight in the first six months of life. What is that extra weight primarily from?

1) Longer bones

2) The weight of knowledge

3) More fat

4) Increases in cell size in response to nutrient intake

5) More cells

5) More cells

Which of the following is NOT made out of living, dividing cells?

1) Stick insects

2) Butterfly wings

3) Coelenterates (Jellyfish and corals)

4) Arachnids (Spiders and scorpions)

5) Echinoderms (starfish and sea urchins)

2) Butterfly wings

Which among the following is incorrect about lysosomes?

1) These are membrane bound vesicles that contain digestive enzymes

2) They digest cellular components as part of autophagy

3) They only degrade proteins

4) Lysosomes degrade cellular constituents, accounting for the majority of cellular protein turnover

5) The pH of lysosomes is essential for efficient protein degradation.

3) They only degrade proteins

Protein folding in the rough endoplasmic reticulum is assisted by:

1) Energy production in form of ATP

2) The formation of disulfide bonds

3) Calcium preventing protein aggregation

4) Modifications in form of phosphorylation (the addition of a phosphate groups).

5) Quick transit time through the RER

2) The formation of disulfide bonds

Which of the following processes relies on the plasma membrane in eukaryotes?

1) Intracellular digestion and breakdown of cellular waste

2) Synthesis and modification of proteins for transport

3) Energy production in the form of ATP

4) The movement of ions and nutrients

5) Storage and regulation of calcium ions

4) The movement of ions and nutrients

Which answer is most correct:

1) The plasma membrane is composed primarily of lipoproteins and proteins

2) The plasma membrane is composed primarily of proteins and lipids

3) The plasma membrane is composed primarily of amino acids and cellulose

4) The plasma membrane is composed primarily of carbohydrates and nucleic acids

5) The plasma membrane is composed primarily of steroids and lipoproteins

2) The plasma membrane is composed primarily of proteins and lipids

The plasma membrane contains specialised molecules called:

1) Steroids and phosphatases

2) Antibodies and antigens

3) Enzymes and hormones

4) Carriers and pumps

5) Cytoskeleton and motors

4) Carriers and pumps

What process occurs from the Golgi apparatus outwards towards the cell membrane?

1) Marcopinocytosis

2) Phagocytosis

3) Exocytosis

4) Endocytosis

5) Clathrin mediated endocytosis

3) Exocytosis

Which of the following statements is the most accurate

1) Phosphoinositides are regulated by cell surface receptors

2) Phosphoinositides are modified proteins

3) Membrane phosphoinositides are important in defining organelle identity

4) Phosphoinositides regulates opening and closing of membrane transporters

5) Phosphoinositides are modified RNA

3) Membrane phosphoinositides are important in defining organelle identity

What is the role of the SNARE complex in protein trafficking?

1) Facilitates protein folding in the cytoplasm

2) Mediates protein folding and modification

3) Promotes vesicle fusion during protein trafficking

4) Regulates protein degradation

5) Transports proteins from the ER to the Golgi apparatus

3) Promotes vesicle fusion during protein trafficking

Which type of uptake from the external environment involves the engulfment of entire cells?

1) Macropinocytosis

2) Phagocytosis

3) Exocytosis

4) Pinocytosis

5) Receptor-mediated endocytosis

2) Phagocytosis

The carbons in the sugar ring of DNA are labelled 1', 2', 3', 4' and 5'. When part of a nucleotide, which carbon does the base attach to?

4'

5'

2'

1'

3'

1'

How many hydrogen bonds would there be if the following DNA strand was double stranded? 5' TGCCTAA 3'

14

18

17

7

21

17

Why doesn't C base pair with a C on the opposite DNA strand?

1) Because the chemical structure of the C nucleotide does not allow base pairing with itself

2) Because C nucleotides cannot undergo hydrogen bonding, regardless of opposite nucleotide

3) Because C nucleotides are only found on one DNA strand

4) Because C nucleotides on the opposite strand are in the same direction

5) It does but it's not very happy about it

1) Because the chemical structure of the C nucleotide does not allow base pairing with itself

What information about a chromosome is LEAST LIKELY to be used to identify it during a karyotype analysis?

1) Whether the p arm is acrocentric

2) The size of the chromosome

3) The banding pattern

4) The location of the telomeres

5) Whether the p arm is the same size as the q arm

4) The location of the telomeres

Which of the following DNA base pairings is correct?

1) T:G, A:G

2) A:T, G:C

3) G:T, A:C

4) G:A, T:C

5) C:G, C:T

2) A:T, G:C

Which of the following shows the correct order of an mRNA structure?

1) 5'Cap - 5'UTR - ORF - 3'UTR - PolyA

2) 3'Cap - 5'UTR - 3'UTR - PolyA - 5'Cap

3) 5'Cap - 5'UTR - Exon 1 - Intron 1 - Exon 2 - 3'UTR - PolyA

4) 5'Cap - 5'UTR - promoter - gene - 3'UTR - PolyA

5) promoter - 5'Cap - ORF - 3'UTR - PolyA

1) 5'Cap - 5'UTR - ORF - 3'UTR - PolyA

For efficient translation to occur, the following components are necessary:

1) mRNA, ribosomes, amino acids

2) tRNA, amino acids, mRNA

3) tRNA, ribosomes, amino acids, mRNA

4) DNA, tRNA, ribosomes, amino acids

5) DNA, ribosomes, amino acids

3) tRNA, ribosomes, amino acids, mRNA

Which of the following statements best describes the process of translation?

1) Production of DNA from an mRNA

2) Production of an mRNA from a gene

3) Production of an mRNA from a protein

4) Production of a protein from a messenger DNA

5) Production of a protein from an mRNA

5) Production of a protein from an mRNA

How do transcription factors (TFs) find the promoter region of a gene and bind to it?

1) Reverse transcriptase determines where TFs will bind

2) All TFs bind randomly to all promoters of every gene

3) TFs do not bind to the promoter region of genes

4) Each TF recognises specific DNA sequences present in gene promoters

5) Ribosomes guide the TFs to specific promoters

4) Each TF recognises specific DNA sequences present in gene promoters

Why is RNA used for transcription and DNA used for our genome?

1) Because DNA is double stranded and RNA is always single stranded

2) Because DNA contains a hydroxyl group (OH) at the 2' carbon

3) Because DNA contains deoxyribose, which is very stable

4) Because DNA contains ribose, which is

5) Because RNA is more stable than DNA

3) Because DNA contains deoxyribose, which is very stable

Following transcription and splicing, the mature mRNA undergoes polyadenylation of its 3' tail. What does this do?

1) stabilises the mRNA

2) blocks the mRNA from being exported out of the nucleus

3) increases the speed of degradation of the mRNA

4) stops alternative splicing of the mRNA

5) changes the coding sequence of the mRNA

1) stabilises the mRNA

Regarding untranslated regions (UTRs), which of the following statements is CORRECT?

1) Untranslated regions are not important for translation

2) Genes have both 5' and 3' untranslated regions

3) Untranslated regions are located within the open reading frame

4) Untranslated regions always code for short proteins which have a function

5) Untranslated regions are not transcribed

2) Genes have both 5' and 3' untranslated regions

What is the role of guanosine triphosphate (GTP) in G protein signalling pathways?

1) It binds to protein kinases

2) It is a precursor molecule for ATP synthesis

3) It plays a direct role in gene expression 

4) It promotes signal transduction

5) It directly binds to tyrosine residues on receptor proteins

4) It promotes signal transduction

What is the main role of Ras proteins in cell signaling?

1) To amplify signals in the nucleus

2) To regulate release of hormones

3) To relay signals from receptor tyrosine kinases to downstream pathways

4) To directly bind to DNA and regulate gene expression

5) To act as second messengers in GPCR signaling

3) To relay signals from receptor tyrosine kinases to downstream pathways

How does autocrine signaling differ from paracrine signaling?

1) Autocrine signaling only involves intracellular pathways, while paracrine signaling involves extracellular factors.

2) Autocrine signaling involves long-range signaling, while paracrine signaling is localized.

3) Autocrine signaling involves signaling molecules acting on the same cell, while paracrine signaling affects neighboring cells.

4) Autocrine signaling affects neighboring cells, while paracrine signaling affects the same cell.

5) Autocrine signaling releases hormones, while paracrine signaling releases neurotransmitters.

3) Autocrine signaling involves signaling molecules acting on the same cell, while paracrine signaling affects neighboring cells.

How do secondary messengers contribute to cell signalling?

1) By activating receptor tyrosine kinases

2) By inducing protein synthesis

3) By directly inducing cellular division

4) By activating gene expression

5) By transmitting cell signals

5) By transmitting cell signals

Which molecule serves as a common second messenger in many cell signaling pathways in human cells?

1) Glucose, a primary source of cellular energy

2) Cyclic adenosine monophosphate (cAMP)

3) Adenosine triphosphate (ATP), the universal energy currency of cells

4) Ribonucleic acid (RNA), involved in protein synthesis

5) Potassium ions, involved in osmotic regulation

2) Cyclic adenosine monophosphate (cAMP)

In cell signalling, which class of molecules are the main contributors?

1) Proteins

2) Lipids

3) Vitamins

4) Carbohydrates

5) Nucleic acids

1) Proteins

Which of the following best describes the purpose of cell signalling?

1) To increase cell size and division rates

2) To modify  cell behavior in response to external cues

3) To active gene expression

4) To ensure proper nutrient uptake and waste removal

5) To maintain cellular metabolism and energy production

2) To modify  cell behavior in response to external cues

Which is most correct?

1) Cell signalling pathways in human cells only respond to hormones and growth factors 

2) 7 helix transmembrane receptors transport signalling molecules across the cell membrane

3) Endocytosis can regulate cell signalling 

4) Cell to cell communication always occurs via plasma membrane receptors

5) Guanosine monophosphate (GMP) can regulate cell signalling

3) Endocytosis can regulate cell signalling 

What is the central role of protein kinases in cell signalling?

1) Protein kinases regulate the activity of target proteins by phosphorylating them

2) Protein kinases degrade proteins within cells 

3) Protein kinases transport signalling molecules across membranes.

4) Protein kinases store energy for cellular activities and regulate metabolic pathways.

5) Protein kinases bind to DNA to control gene expression directly.

1) Protein kinases regulate the activity of target proteins by phosphorylating them

Which organelle release calcium ions crucial for various signalling pathways?

1) Nucleus

2) Lysosome

3) Golgi apparatus

4) Endoplasmic reticulum (ER)

5) Mitochondria

4) Endoplasmic reticulum (ER)

What is anterograde transport for?

1) Propagating depolarisation along the length of an axon

2) Moving dyneins to the plus ends of microtubules

3) It is the capping of microtubule minus ends that allows growth and extension of microtubules from the plus end

4) Moving chromosomes toward the spindle pole in anaphase

5) Moving mitochondria to the end of axons via kinesins

5) Moving mitochondria to the end of axons via kinesins

What promotes loss of actin from the minus end of microfilaments and gain of actin at the plus end?

1) Actin being bound to ADP or ATP

2) Actin being embedded in focal adhesions at the cell membrane

3) Capping by profilin

4) Phosphorylation or dephosphorylation of actin subunits

5) Bundling and crosslinking via alpha-actinin

1) Actin being bound to ADP or ATP

Which of the following molecules would you expect to find at focal adhesions?

1) Kinesins

2) Microtubule minus ends

3) Actin filaments

4) Muscle myosin filaments

5) Lamin fibres

3) Actin filaments

Which of the following is a feature of Microtubules?

1) Stable fibre lengths

2) Primarily found around the cell cortex

3) Associated with myosin motors

4) Anchored in hemidesmosomes

5) Polarity mediated by GTP/GDP binding

5) Polarity mediated by GTP/GDP binding

What is the main role of filopodia?

1) To build broad attachment surfaces for cell adhesion

2) To find and engulf bacteria

3) To explore the substrate around the cell

4) To increase the surface area of gut cells, increasing absorbtion

5) To establish channels for cell-cell communication

3) To explore the substrate around the cell

How does cytokinesis work?

1) The two daughter cells migrate apart in telophase, pulling the cell in two

2) A ring of actin filaments anchored in the membrane is pulled tight by myosin filaments

3) The microtubule spindle contracts at the end of mitosis, pulling in the cell membrane

4) The membrane at the centre of the cell is connected to the nuclei, which separate in anaphase, pulling in the membrane to separate the daughter cells

5) Plus end directed dynein motors pull the cell membrane along the astral microtubules to separate the daughter cells

2) A ring of actin filaments anchored in the membrane is pulled tight by myosin filaments

How does muscle contraction work?

1) Tropomyosin responds to a Calcium signal by pulling the actin filaments

2) Actin in sarcomeres depolymerises when the nerve signal is received, shortening the muscle

3) Muscle myosin is a minus end directed motor and responds to nerve signals by using ATP to push the plus ends apart

4) ATP is broken down, and the energy released is used to push the Z discs apart

5) Calcium release allows myosin heads to walk toward the plus ends of actin filaments powered by ATP hydrolysis

5) Calcium release allows myosin heads to walk toward the plus ends of actin filaments powered by ATP hydrolysis

Which of the following best describes how cell motility occurs?

1) Actin/myosin sarcomeres contract in response to the release of cytoplasmic Calcium ions

2) The cell membrane is extended by microvilli and retracted at the trailing edge by lamellipodia

3) Actin fibres anchored in the substrate are pulled together by myosin

4) Cells extend pseudopodia that find adhesion points, then contract pulling the cell forward

5) Microtubules anchored in the membrane by kinesin complexes pull the membrane via depolymerisation

3) Actin fibres anchored in the substrate are pulled together by myosin

Why are actin filaments described as dynamic?

1) Because they get longer or shorter over time

2) Because they use ATP to drive cell motility

3) Because they form networks that stabilise the cell membrane

4) Because they are essential for muscle attachment sites

5) Because they move during muscle contraction

1) Because they get longer or shorter over time

What is the primary role of intermediate filaments?

1) They are used to separate the DNA in mitosis

2) They are used as the main protein motor substrate for transporting vesicles in long axons

3) They are used for muscle contraction

4) They are stable, lasting fibres used to anchor cell architecture

5) They are used for cell motility

4) They are stable, lasting fibres used to anchor cell architecture

Which of the following best describes the structure of proteoglycans?

1) A core chain of heparan sulfate is bound by multiple different chains of amino acids (peptides)

2) They are formed by hydroxylation of prolines, leading to crosslinking of triple helix fibres

3) Multiple chains of sugars are attached to a core protein, which may in turn be attached to a sugar chain such as hyaluronan

4) Branched chains of sugars are crosslinked together to form a meshwork

5) A protein meshwork, such as the basal lamina, has short sugar chains attached, one or two per laminin trimer

3) Multiple chains of sugars are attached to a core protein, which may in turn be attached to a sugar chain such as hyaluronan

Which of the following statements about integrins is CORRECT?

1) Integrins are used to form an apical watertight barrier

2) Integrins bind identical integrins on adjacent cells in the presence of Calcium ions

3) Integrins can be activated to bind ECM by signals from inside the cell

4) There are four dimeric integrins found in humans, and their role is to bind growth factors in the blood and transmit that signal into the cell to drive proliferation.

5) Integrins are found as a trimeric receptor that binds ECM ligands such as proteoglycans

3) Integrins can be activated to bind ECM by signals from inside the cell

Why does collagen make such strong, stable extracellular matrix?

1) Because it is formed from a highly crosslinked triple helix

2) Because it is hydroxylated, and the hydroxy-alanine residues are crosslinked to the plasma membrane

3) Because the chains are negatively charged and hydrated sugars, making a shock absorbing gel

4) Because it is calcified with phosphates to make rigid structures

5) Because it is made out of GTP-bound tubulin dimers that polymerise into a long fibre

1) Because it is formed from a highly crosslinked triple helix

Which transmembrane molecule is primarily responsible for cell-ECM attachment and is essential for cell motility?

1) Integrins

2) Selectins

3) Laminins

4) Collagens

5) Cadherins

1) Integrins

What does Vitamin C have to do with the extracellular matrix?

1) It is needed for proper degradation of glycosaminoglycans, which otherwise build up in the lysosomes

2) It is needed for proline hydroxylation, which is needed for collagen stability

3) It is needed to prevent rickets (insufficient bone calcification)

4) It is needed for laminin structure, so deficiency leads to loss of basement membrane stabililty

5) It is needed for scavenging reactive oxygen species to prevent retinal degeneration

2) It is needed for proline hydroxylation, which is needed for collagen stability

What is the difference between desmosomes and hemidesmosomes?

1) Hemidesmosomes are approximately half as strong an adhesive junction as desmosomes

2) Hemidesmosomes are attached to intermediate filaments, while desmosomes are attached to microtubules

3) Hemidesmosomes are apical, while desmosomes are baso-lateral

4) Desmosomes attach laterally to other desmosomes, while hemidesmosomes attach basally to the ECM

5) Desmosomes primarily attach to actin microfilaments, while hemidesmosomes attach to microtubules

4) Desmosomes attach laterally to other desmosomes, while hemidesmosomes attach basally to the ECM

What are gap junctions for?

1) To help cells select and bind to similar cells

2) To hold together adjacent cells in an epithelium

3) To hold epithelial layers down onto the basement membrane

4) To allow adjacent cells to share cytoplasm

5) To make a barrier at the apical surface of epithelia

4) To allow adjacent cells to share cytoplasm

What are tight junctions for?

1) To allow adjacent cells to share cytoplasm

2) To help cells select and bind to similar cells

3) To hold epithelial layers down onto the basement membrane

4) To mark the basolateral surface of the cell membrane

5) To make a barrier at the apical surface of epithelia

5) To make a barrier at the apical surface of epithelia

What is the primary defect in Sanfillipo syndrome?

1) Lysosome failure due to buildup of heparan sulfate

2) Loss of basement membranes

3) Failure to synthesise glycosaminoglycans such as aggrin

4) Dietary deficiencies lead to a lack of proteoglycans

5) Loss of collagen IV structural integrity

1) Lysosome failure due to buildup of heparan sulfate

What are hemidesmosomes for?

1) To hold together adjacent cells in a epithelium

2) To hold epithelial layers down onto the basement membrane

3) To allow adjacent cells to share cytoplasm

4) To help cells select and bind to similar cells

5) To make a barrier at the apical surface of epithelia

2) To hold epithelial layers down onto the basement membrane

Which of the following accurately describes cytokinesis?

1) It involves the separation of sister chromatids.

2) It is the division of the cytoplasm.

3) It occurs during the G1 phase.

4) It occurs after cell cycle exit

5) It takes place during the S phase.

It is the division of the cytoplasm.

What is the purpose of the G2/M checkpoint in the cell cycle?

1) To ensure proper spindle formation and chromosome attachments

2) To promote DNA replication

3) To check for DNA damage

4) To assess cell size and nutrient availability

5) To regulate exit from the cell cycle

To check for DNA damage

Which phase immediately follows the S phase of the cell cycle

1) M phase

2) Cytokinesis

3) G0

4) G2 Phase

5) G1 phase

G2 Phase

What follows anaphase?

1) Antiphase

2) Anaphase

3) Prophase

4) Telophase

5) Metaphase

Telophase

What happens during the G2 phase of the cell cycle?

1) Cells grow

2) DNA replication 

3) Nuclear envelope breakdown 

4) Cells enter a dormant state

5) Chromosomes alignment

Cells grow

How does the G1 phase contribute to cell cycle progression?

1) By regulating nuclear envelope breakdown

2) By regulating chromosome attachment

3) By initiating DNA replication.

4) By allowing the cell to grow and prepare for DNA replication

5) By regulating Spindle formation

By allowing the cell to grow and prepare for DNA replication

Which statement best describes the purpose of mitosis?

1) Mitosis results in two genetically identical daughter cells

2) Mitosis produces haploid cells.

3) Mitosis occurs during the S phase of the cell cycle

4) Mitosis contributes to genetic diversity.

5) Mitosis prevents formation of DNA double strand breaks

Mitosis results in two genetically identical daughter cells

What role does the cell cycle play in the development of cancer ?

1) It enhances cell growth

2) It prevents cell death 

3) If unregulated it can led to uncontrolled cell proliferation

4) Ensures normal cell growth and differentiation

5) Prevents the accumulation of mutations in cells

If unregulated it can led to uncontrolled cell proliferation

What is the role of cohesion ?

1) Regulating cell growth

2) Facilitating DNA replication accuracy.

3) Promoting spindle formation

4) Keeping chromatids together 

5) Facilitating chromatid segregation

Keeping chromatids together

What is the purpose of the cell cycle?

1) To promote the elimination of damaged cells

2) To allow cells to grow and replicate their DNA before division

3) To ensure rapid cell division

4) To ensure the formation of specialised cell types

5) To maintain a constant cell size

To allow cells to grow and replicate their DNA before division

Under what conditions might a cell increase its demand  for exogenously obtained amino acids?

When producing energy via glycolysis.

, Not Selected

When duplicating its DNA

, Not Selected

When segregating its chromosomes

, Not Selected

Correct answer:

When engaged in translation

When undergoing transcription

How might nutrient availability relate to cancer cells?

Nutrient availability has no impact on cancer development.

, Not Selected

Nutrient availability has minor impact on cancer cells

, Not Selected

Cancer cells rely on uptake for all their amino acids.

, Not Selected

Cancer cells can synthesise all its own amino acids

, Not Selected

Correct answer:

Increased availability is likely to promote cancer cell growth 

How does nutrient availability relate to the size of organisms as they develop?

Larger organisms require more nutrients per kg of body weight due to less efficient metabolic processes.

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Nutrient availability is independent of organism size.

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Correct answer:

Eukaryotes typically adjust their size in response to nutrient availability

High levels of amino acids block mTORC1 signalling to keep cell size constant

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Organism size is set genetically and can not be changed 

What is the primary role of ATP in cells?

To transport oxygen within the cell.

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To regulate cell membrane permeability.

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Correct answer:

To serve as a source of chemical energy.

To store genetic information.

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To provide structural support to the cell.

How is ATP replenished in cells during periods of high energy demand

Through glycolysis.

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Through DNA replication.

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Through cell division.

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Through protein synthesis.

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Incorrect answer:

Through cellular uptake

Correct Answer:

Through glycolysis.

Which amino acids must be obtained through the diet in humans?

All 20 amino acids.

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None of the amino acids.

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Correct answer:

A subset of amino acids because the body can’t synthesise them.

Only the charged amino acids.

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Only the noncharged amino acids.

How does size relate to cellular function?

Correct answer:

The need to efficently pass nutrients and waste into and out of the cell sets a limit on how big cells can be.

Relative to their size, smaller cells needs less energy.

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Control of cell size is not import for living organisms

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larger cells can engulf larger nutrients more effectively.

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Larger cells experience fewer mutations during DNA replication.

How can AMP activated protein kinase (AMPK) regulate gene expression

1) AMPK kinase regulate chromosome localisation

2) AMPK kinase regulates mRNA nuclear export

3) AMPK kinase can inhibit transcription and translation through inhibition of mTOR

4) AMPK kinase enhances general mRNA transcription and translation in response to nutrient stress

5) AMPK kinase has no impact on gene expression

What frequently happens when mTOR kinase signalling is upregulated

1) It blocks nutrient uptake

2) It accelerates protein degradation.

3) It promotes autophagy.

4) It promotes cell growth and cell proliferation 

5) It has no impact on cellular processes.

4) It promotes cell growth and cell proliferation

What is a major role of the mTOR kinase in cellular metabolism?

1) It has no impact on cellular metabolism

2) To induce cell cycle arrest in G0 (cellular quiescence).

3) To stimulate protein synthesis

4) To suppress metabolic pathways.

5) To promote autophagy.

3) To stimulate protein synthesis

What happens to cells that go through apoptosis?

1) They break open, releasing their contents to be digested by phagocytes

2) They undergo multiple rapid rounds of cell division to end up with a lot of tiny daughter cells

3) They fragment into small membrane-bound remnants before being phagocytosed

4) They release inflammatory mediators like NF-kB to attract monocytes to engulf them

5) They undergo an epithelial to mesenchymal transition (EMT)

3) They fragment into small membrane-bound remnants before being phagocytosed

What can happen to the extrinsic apoptosis signalling pathway in cancer?

1) Mutations are often found in Bcl2, so the extrinsic pathway is typically overactive in cancer

2) Common mutations in p53 mean that Bax and Bak are overactive in cancer

3) Cytochrome c release is blocked, so the extrinsic pathway does not work

4) The extrinsic apoptosis pathway can be used to drive proliferation

5) Because mitochondria are not used in cancer, the extrinsic pathway is no longer available

4) The extrinsic apoptosis pathway can be used to drive proliferation