hllj/quesmed huggingface dataset:
A medical student is shadowing a morning theatre list. She observes a doctor obtaining informed consent from a patient. They are notified of all associated risks.

Which of the following principles is being described in the scenario above?

Options:
explanation: The Doctrine of Double Effect explains how we can accept an action if the intention is to cause a 'good outcome' (e.g. pain relief), even if it may foreseeably lead to a 'bad outcome' (e.g. death).
name: Doctrine of Double Effect
label: c
answer: no
explanation: If someone cannot make a specific decision, a decision may have to be made in their best interests. This means that a decision will be made on their behalf, having been considered from their point of view.
name: Best interest decisions in patients who lack capacity
label: e
answer: no
explanation: Principle of autonomy describes the modern medicine approach of patient-centred medicine. This principle means that a patient should be provided with enough information and support to make their own informed decision about their healthcare, and this decision should be respected.
name: Principle of autonomy
label: d
answer: no
explanation: The Bolam test established that a doctor will not be found negligent if he/she acts with ordinary care and his/her actions are sanctioned by a responsible body of medical opinion.
name: Bolam test
label: b
answer: no
explanation: Montgomery Ruling describes how much information should be given to patients about the risks of a procedure, to obtain valid informed consent.
name: Montgomery ruling
label: a
answer: yes

Correct answer: a
Which of the following structures is exclusively present within a plant cell?

Options:
explanation: A plasma membrane is formed from lipids and proteins. It allows for a boundary to be formed between the cell contents and the outside of a cell, thus controlling what can and cannot enter. This is present in both plant and animal cells.
name: Plasma membrane
label: b
answer: no
explanation: A chloroplast is an organelle exclusively in plants which contains chlorophyll. This allows for light energy to be converted into chemical energy in a process known as photosynthesis.
name: Chloroplast
label: a
answer: yes
explanation: This structure is present in both animal and plant cells. It carries out oxidative phosphorylation and produces ATP which is a primary energy source for cellular functions.
name: Mitochondria
label: c
answer: no
explanation: This is present within plant and animal cells. It allows for further processing and modification of proteins from the endoplasmic reticulum. These proteins are then packaged into vesicles.
name: Golgi apparatus
label: e
answer: no
explanation: The nucleus is present in both plant and animal cells. It contains genetic material which allows for protein synthesis and cellular growth.
name: Nucleus
label: d
answer: no

Correct answer: a
Which of the following statements describes the tertiary structure of a protein?

Options:
explanation: This is correct as it describes the tertiary structure of a protein.
name: A three-dimensional conformation that requires the lowest amount of energy
label: a
answer: yes
explanation: This describes the quaternary structure of a protein.
name: A complex made up of more than one polypeptide chain
label: b
answer: no
explanation: This describes the secondary structure of a protein.
name: An alpha helix which contains non-covalent hydrogen bonds
label: d
answer: no
explanation: This describes the secondary structure of a protein.
name: A beta-pleated sheet which contains non-covalent hydrogen bonds
label: e
answer: no
explanation: This describes the primary structure of a protein.
name: An amino acid sequence with covalent peptide bonds
label: c
answer: no

Correct answer: a
Which one of the following is true regarding cholesterol and the plasma membrane?

Options:
explanation: Cholesterol makes the plasma membrane less fluid by stabilising interactions between neighbouring phospholipids. As a result, the outer surface of the membrane is immobilised and very small water-soluble molecules are less likely to freely move across. This reduces membrane permeability.
name: Cholesterol makes the membrane more permeable
label: e
answer: no
explanation: At 37°C cholesterol stabilises interactions between neighbouring phospholipids. Cholesterol immobilises the outer surface of the membrane and reduces fluidity. Therefore, very small water-soluble molecules are less likely to freely move across.
name: At 37°C cholesterol tends to make the plasma membrane less fluid
label: a
answer: yes
explanation: Cholesterol is absent from prokaryotic cells.  Cholesterol provides structural integrity to eukaryotic cells which is why animal cells do not require a cell wall.
name: Cholesterol is present in the plasma membrane of eukaryotes and prokaryotes
label: d
answer: no
explanation: Phospholipids are derived from triglycerides and contain 2 fatty acid chains, glycerol and a phosphate group.
Cholesterol is a type of steroid. It is an organic molecule which contains 4 rings.

Cholesterol and phospholipids are both a type of lipid but they have different chemical structures, therefore, cholesterol cannot be a type of phospholipid.
name: Cholesterol is a phospholipid
label: c
answer: no
explanation: At 37°C cholesterol will stabilise interactions between neighbouring phospholipids. It immobilises the outer surface of the membrane and reduces fluidity, therefore this answer is incorrect.
name: At 37°C cholesterol tends to make the plasma membrane more fluid
label: b
answer: no

Correct answer: a
Which germ layer will give rise to the digestive tract?

Options:
explanation: The cephalo-caudal folding of the embryo encloses the endoderm-lined cavity inside. This forms the primitive gut tube which eventually forms the digestive tract.
name: Endoderm
label: a
answer: yes
explanation: Mesoderm separates into 3 columns: paraxial, lateral plate and intermediate mesoderm. The lateral plate mesoderm forms the visceral layer lining organs and the parietal layer lining the body wall.
name: Lateral plate mesoderm
label: e
answer: no
explanation: This germ layer forms the skeletal, muscular and circulatory systems and connective tissues.
name: Mesoderm
label: c
answer: no
explanation: Mesoderm separates into 3 columns: paraxial, lateral plate and intermediate mesoderm. Intermediate mesoderm forms urogenital structures.
name: Intermediate mesoderm
label: d
answer: no
explanation: This germ layer will form the neural plate or neuroectoderm which eventually gives rise to the epidermis and nervous tissues.
name: Ectoderm
label: b
answer: no

Correct answer: a
Which one of the following describes facilitated diffusion?

Options:
explanation: This is an example of osmosis as water is moving from an area of high concentration to an area of low concentration through a semi-permeable membrane.
name: Water moves down its concentration gradient through a semi-permeable membrane with no carrier proteins involved
label: d
answer: no
explanation: Glucose is transported via the uniporter protein Glut2 within the gut epithelium. Glut2 is a carrier protein transporting glucose from an area of high concentration to an area of low concentration. Therefore this is an example of facilitated diffusion.
name: Glucose transported via the Glut2 transporter within the gut epithelium
label: a
answer: yes
explanation: Oxygen is an uncharged molecule which can pass through the lipid bilayer without assistance from any membrane proteins. This is an example of simple diffusion.
name: Oxygen moves down its concentration gradient through the lipid bilayer with no membrane proteins involved
label: b
answer: no
explanation: This is an example of active transport as the Na+K+ATPase hydrolyses ATP to ADP and uses ENERGY to expel Na+ outside of the cell from an area of low Na+ concentration to an area of high Na+ concentration.
name: The Na+K+ATPase transporting Na+ outside of the cell
label: c
answer: no
explanation: Carbon Dioxide is an uncharged molecule which can pass through the lipid bilayer without assistance from any membrane proteins. This is an example of simple diffusion.
name: Carbon Dioxide moves down its concentration gradient through the lipid bilayer with no membrane proteins involved
label: e
answer: no

Correct answer: a
Which one of the following best describes the function of the G2 checkpoint within the cell cycle?

Options:
explanation: This is incorrect. The G2 checkpoint is located after the S phase of the cell cycle and not after the M phase therefore it cannot ensure that cytoplasmic division has occurred successfully.
name: To ensure that cytoplasmic division has occurred successfully
label: e
answer: no
explanation: This is incorrect as it is describing the G1 checkpoint. The G1 checkpoint is known as the restriction point, if a cell does not pass this checkpoint it enters quiescence by switching to a non-dividing state known as G0.
name: To allow for the cell to exit the cell cycle and switch to a non-dividing state known as G0 if it does not pass the checkpoint
label: d
answer: no
explanation: This is incorrect as it is describing the G1 checkpoint. The G1 checkpoint is known as the restriction point, if a cell passes this point it is usually able to continue with the cell cycle.
name: Ensures that the cell is large enough to divide and that enough nutrients are available to support the daughter cells
label: c
answer: no
explanation: This is incorrect as it is describing the metaphase checkpoint. The metaphase checkpoint ensures that the cell is in the right condition to move on.
name: Ensures that all of the chromosomes are attached to the mitotic spindle by a kinetochore
label: b
answer: no
explanation: The G2 checkpoint is located after the S phase. This is to ensure that replication has been completed successfully before the cell enters the G2 phase.
name: Ensures that DNA replication in the S phase has been completed successfully
label: a
answer: yes

Correct answer: a
There are many proteins located within the cell cycle at specific checkpoints.

Which of the following will occur if there is a damaged/non-functional p53 protein?

Options:
explanation: p53 damage/loss will cause a loss of function mutation leading to damaged DNA and genome instability. This will result in an increased rate of mutation.
name: Genome stability
label: d
answer: no
explanation: p53 damage/loss will cause unrestrained replication of damaged DNA which will further result in genome instability and cause resistance to apoptosis as a result of mutation accumulation.
name: Unrestrained replication of damaged DNA
label: a
answer: yes
explanation: This statement describes what would occur if p53 were functional.
name: Prevents the continuation of the cell into the S phase, giving time for DNA repair
label: b
answer: no
explanation: This statement describes what would occur if p53 were functional.
name: p53 induces the cell to kill itself by apoptosis if the DNA damage is too severe
label: c
answer: no
explanation: p53 will cause sustained proliferative signalling leading to an increased rate of mutation if it is damaged/mutated.
name: Unsustained proliferative signalling
label: e
answer: no

Correct answer: a
A cell which can give rise to all embryonic and adult lineages is known as which one of the following?

Options:
explanation: A cell which is can give rise to cells within a specific lineage.
name: Multipotent
label: b
answer: no
explanation: A cell which can only differentiate into a singular tissue.
name: Unipotent
label: d
answer: no
explanation: This is a cell which can give rise to all embryonic and adult cell lineages.
name: Totipotent
label: a
answer: yes
explanation: This is a made-up term and does not refer to the statement above.
name: Wholepotent
label: e
answer: no
explanation: A cell which can give rise to all of the cell types within an adult lineage.
name: Pluripotent
label: c
answer: no

Correct answer: a
Which type of inheritance can be seen in the following pedigree?

[lightgallery]

Options:
explanation: In an autosomal recessive pedigree you usually cannot follow the disease throughout the pedigree. You see horizontal transmission (siblings affected) and an equal incidence of males and females affected. Note that there may be evidence of consanguinity.
name: Autosomal recessive inheritance
label: b
answer: no
explanation: This is usually shown on a pedigree by a double line drawn between two people. This suggests that two people are 'related by blood' and therefore, have a common ancestor.
name: Consanguinity
label: e
answer: no
explanation: Maternal inheritance on a pedigree would show all offspring to be affected as the mothers pass on mitochondria from their egg. The sperm's mitochondria are actively expelled from the fertilised egg and therefore not passed on to offspring.
name: Maternal inheritance
label: c
answer: no
explanation: An X-linked dominant pedigree will appear similar to an autosomal dominant pedigree. However, there will be an excess of affected females and no male-to-male transmission.
name: X-linked dominant disease
label: d
answer: no
explanation: This is correct. This is because within this pedigree you see affected people in each generation. Both males and females are affected but more importantly, all forms of transmission are seen including male-to-male transmission.
name: Autosomal dominant inheritance
label: a
answer: yes

Correct answer: a
In which layer of the epidermis are Merkel cells present?

Options:
explanation: This layer is located above the stratum basale. It usually contains several layers of keratinocytes which are attached by desmosomes, hence giving a 'spine-like' appearance.
name: Stratum spinosum
label: b
answer: no
explanation: This layer only exists in thick skin which has 5 layers.
name: Stratum lucidum
label: d
answer: no
explanation: This layer contains basal cells which serve as stem cells for the epithelium. These cells divide and produce keratinocytes which move up through the different layers of the epidermis. Within this layer melanocytes and Merkel cells are present.
name: Stratum basale
label: a
answer: yes
explanation: This is usually 1-3 layers thick and contains keratinocytes. Here the keratinocytes contain keratohyalin granules.
name: Stratum granulosum
label: c
answer: no
explanation: This is the uppermost layer of the epidermis. It contains corneocytes (originally keratinocytes before moving to the final layer) which have no nuclei or cytoplasmic organelles. These are eventually desquamated (detached from the skin).
name: Stratum corneum
label: e
answer: no

Correct answer: a
In which of the following situations does the application of the Hardy-Weinberg equilibrium hold true?

Options:
explanation: The Hardy-Weinberg equilibrium refers to what a population looks like when it is not evolving, the population will stay the same over generations. As a result, there should be **no** preferential selection of genotypes and therefore no evolving for the equilibrium to be applied.
name: No preferential selection of genotypes
label: a
answer: yes
explanation: Smaller populations would be more susceptible to genetic drift (change in an allele frequency). Therefore, the populations should be as close to infinite in size to apply to this equilibrium.
name: Smaller populations
label: c
answer: no
explanation: If new alleles are present this can be a strong agent of evolution. Therefore, to be applicable to the equilibrium there should be **no** new alleles present
name: New alleles present
label: d
answer: no
explanation: Random mating is required for this equilibrium to hold true. This is because reproduction will then be the result of two random events so the probability of any offspring genotype will be the probability of the sperm and egg producing that genotype.
name: Non-random mating
label: b
answer: no
explanation: If there is a preferential selection of genotypes, the more advantageous genotype will be reproduced and will survive in a given environment. If an allele becomes less advantageous its frequency will drop throughout generations. Therefore, there should be **no** preferential selection of genotypes for the equilibrium to be applied.
name: Preferential selection of genotypes
label: e
answer: no

Correct answer: a
Which one of the following describes a nonsense mutation?

Options:
explanation: This describes a splice-site mutation. If there is a change in introns then the mutation may not affect the phenotype. If the splice site becomes mutated there will be incorrect splicing of pre-messenger RNA therefore, an altered RNA sequence and altered protein will be produced.
name: A mutation in a splice site produces an altered RNA sequence
label: e
answer: no
explanation: This describes a silent mutation. The amino acid is not altered so there is no alteration in the polypeptide composition of the protein.
name: A single base substitution which alters the genetic code but not the amino acid
label: b
answer: no
explanation: This describes a nonsense mutation. The premature termination of translation produces a truncated protein which is unlikely to carry out its normal activities.
name: A termination codon is created: UAA, UAG, UGA resulting in premature termination of translation
label: a
answer: yes
explanation: This describes a frameshift mutation. An insertion or deletion of a nucleotide that is not a multiple of three will change each amino acid sequence downstream. A new stop codon will be formulated thus causing a shortened altered protein to be expressed.
name: An insertion or deletion of base pairs that produce a stop codon downstream
label: d
answer: no
explanation: This describes a missense mutation. If the amino acid which is coded for is chemically dissimilar to the amino acid that should be there, the structure and function of the protein will be altered. If the amino acid is chemically similar there could be conservation of the biological activity of the protein.
name: A single base substitution which codes for a different amino acid
label: c
answer: no

Correct answer: a
Which of the following is the syndrome associated with trisomy 18?

Options:
explanation: This occurs in 1 in 1000 male births. In this syndrome, the male is born with an extra X chromosome. This predisposes to infertility, poor development of secondary sexual characteristics and being very tall.
name: Klinefelter's syndrome
label: e
answer: no
explanation: This is trisomy 13.
This occurs in 1 in 5000 births. It causes multiple malformations: affecting midline structures. There is incomplete lobation of the brain, cleft lip and congenital heart disease.
name: Patau syndrome
label: c
answer: no
explanation: This is trisomy 21.
In this syndrome, the baby is born with an extra copy of chromosome 21. This causes intellectual disability and abnormalities such as upslanted palpebral fissures and a flat nasal bridge.
name: Down's syndrome
label: b
answer: no
explanation: This occurs in 1 in 3000 births. This condition causes multiple malformations, especially in the heart and kidneys and is not compatible with life.

NB Trisomy refers to an extra copy of a chromosome within the nucleus. This often leads to developmental disorders.
name: Edward's syndrome
label: a
answer: yes
explanation: This is a condition where a female is born with one of her X chromosomes missing. This characteristically causes short stature, failure of the ovaries to develop and heart defects.
name: Turner's syndrome
label: d
answer: no

Correct answer: a
The following description describes which type of signalling: a cell which produces a signal that will act on and induce changes in nearby cells'?

Options:
explanation: This is when a cell produces a signal such as a hormone that acts on intracellular receptors within the cell.
name: Intracrine signalling
label: d
answer: no
explanation: This is when a cell produces a signal which will act on the cell surface and induce changes within neighbouring cells that are physically in contact with the one releasing the signal.
name: Juxtacrine signalling
label: c
answer: no
explanation: This is a type of cell signalling where signals e.g. hormones are released and travel within the bloodstream to act on distant target cells.
name: Endocrine signalling
label: e
answer: no
explanation: The definition for this is the one mentioned in the question.
name: Paracrine signalling
label: a
answer: yes
explanation: This is when a cell produces a signal which will act on the cell surface and induce changes in itself.
name: Autocrine signalling
label: b
answer: no

Correct answer: a
Which one of the following is correct regarding the pharmacology of cholera toxin?

Options:
explanation: Cholera toxin works at Gs receptors inhibiting GTPase to prevent GTP hydrolysis. This leads to constant activation of adenylyl cyclase and elevated cAMP levels thus causing excess secretion of water. This results in diarrhoea and possible death if untreated.
name: Cholera toxin works at Gs receptors causing increased cAMP levels
label: a
answer: yes
explanation: Cholera toxin works at Gs receptors inhibiting GTPase to prevent GTP hydrolysis. This leads to constant activation of adenylyl cyclase and elevated cAMP levels thus causing excess secretion of water. This results in diarrhoea and possible death if untreated.
name: Cholera toxin works at Gs receptors causing decreased cAMP levels
label: b
answer: no
explanation: Cholera toxin works at Gs receptors inhibiting GTPase to prevent GTP hydrolysis. This leads to constant activation of adenylyl cyclase and elevated cAMP levels thus causing excess secretion of water. This results in diarrhoea and possible death if untreated.
name: Cholera toxin works at Gs receptors causing decreased secretion of water in the gastrointestinal tract
label: e
answer: no
explanation: Cholera toxin works at Gs receptors inhibiting GTPase to prevent GTP hydrolysis. This leads to constant activation of adenylyl cyclase and elevated cAMP levels thus causing excess secretion of water. This results in diarrhoea and possible death if untreated.
This specific statement refers to the pertussis toxin.
name: Cholera toxin works at Gi receptors causing increased cAMP levels
label: c
answer: no
explanation: Cholera toxin works at Gs receptors inhibiting GTPase to prevent GTP hydrolysis. This leads to constant activation of adenylyl cyclase and elevated cAMP levels thus causing excess secretion of water. This results in diarrhoea and possible death if untreated.
name: Cholera toxin works at Gi receptors causing decreased cAMP levels
label: d
answer: no

Correct answer: a
Which of the following is a hormone released by the posterior pituitary gland?

Options:
explanation: This is produced by the ANTERIOR pituitary and is released throughout life. Its release is stimulated by hypoglycaemia, exercise and sleep.
name: Growth hormone (GH)
label: d
answer: no
explanation: This is produced by the ANTERIOR pituitary and acts on the adrenal gland to release glucocorticoids and weak androgens.
name: Adrenocorticotrophic hormone (ACTH)
label: c
answer: no
explanation: This is produced by the ANTERIOR pituitary and stimulates the release of T4 from the thyroid. This usually controls metabolism.
name: Thyroid-stimulating hormone (TSH)
label: b
answer: no
explanation: This is produced by the ANTERIOR pituitary. In males, FSH/LH promotes the production of sperm and testosterone. In females, FSH/LH promotes the production of oestrogens, stimulation, maturation and release of egg follicles.
name: LH/FSH (Luteinising hormone/ Follicle stimulating hormone)
label: e
answer: no
explanation: This is released by the posterior pituitary to determine the rate of free water excretion. If there is more ADH released there will be increased water retention and decreased urine output.
name: Anti-diuretic hormone (ADH)
label: a
answer: yes

Correct answer: a