Mock Questions Flashcards
1
Q
State 3 anabolic processes that the TCA cycle provides precursors for.
A
Amino acid synthesis.
Haem synthesis.
Fatty acid synthesis.
Glucose synthesis.
2
Q
Name 3 cardiac defects that lead to left to right shunts.
A
Ventricular septal defect.
Atrial septal defect.
Patent ductus arteriosus.
3
Q
What type of tissue are benign adenomas of the colon formed from?
A
Glandular epithelial tissue.
4
Q
What can cause tumourigenesis?
A
Smoking.
Alcohol consumption.
Diet.
Obesity.
Human papilloma virus.
Epstein Barr virus.
UV radiation from the sun.
Ionising radiation.
5
Q
What oxygen saturation should oxygen be given for?
A
Anything below 92%.
6
Q
What is the scoring system used to determine the likelihood of DVT?
A
Wells’ score/ criteria.
7
Q
Explain how paracetamol overdose can cause liver damage.
A
When in excess, the paracetamol saturates the normal pathway.
This means the oxidation metabolite NAPQI builds up.
NAPQI has a directly toxic effect on hepatocytes.
NAPQI is removed by glutathione so diminishes the levels, which is an important anti-oxidant.
8
Q
Define the term homeostasis.
A
The control of the internal environment within set limits via a dynamic equilibrium.
9
Q
What is BMR and what factors can affect BMR?
A
It is the required energy for function of tissues at physical, digestive and emotional rest, affected by:
- Body weight.
- Body temperature.
- Gender.
- Thyroid status.
- Pregnancy.
- Lactation.
10
Q
What is meant by health inequalities?
A
The unfair or avoidable differences in life expectancy, mortality, morbidity and disability between groups within the same population.
11
Q
State the social determinants of health inequalities.
A
Social class.
Age.
Gender.
Ethnicity.
Disability.
Homelessness.
Deprivation.
12
Q
Where is the left aortic sinus located?
A
Above the left leaflet of the aortic valve.
13
Q
What bacteria commonly cause community-acquired pneumonia?
A
Streptococcus pneumoniae.
Haemophilus influenzae.
Staphylococcus aureus.
Mycoplasma pneumoniae.
Chlamydophilia pneumoniae.
14
Q
What is the purpose of lactate production?
A
Oxide NADH back to NAD+.
Allow energy production in cells with no mitochondria.
Precursor for gluconeogenesis.
Maintain energy production in low oxygen availability.
15
Q
Explain how lactate is used in the body.
A
It circulates the blood and is then taken up by the liver, heart and kidney.
Lactate is then converted to pyruvate by lactate dehydrogenase.
Pyruvate is then:
- Used for energy in the heart.
- Used as a precursor for gluconeogenesis in the liver.
- Used as a precursor for gluconeogenesis in the kidney.
16
Q
What are muscle cramps caused by?
A
Acidosis.
17
Q
What molecules can cause metabolic acidosis?
A
Ketone bodies - acetoacetate, beta-hydroxybutyrate.
Pyruvate.
Fatty acids.
Amino acids.
ATP.
18
Q
What is the function of dystrophin?
A
Links the cytoskeleton to the plasma membrane.
It acts as a shock absorber.
It stabilises the muscle, mechanically.
Regulates calcium levels.
19
Q
Why is embryogenesis classed as mitosis?
A
They are somatic cells.
20
Q
What does the autoantibody in Graves’ disease act on?
A
TSH receptors.
21
Q
What are 3 ways of treating patients with Graves’ disease?
A
Carbimazole - inhibits thyroid peroxidase.
Radioactive iodine - destroys the glandular cells, decreasing thyroid production.
Surgical intervention - removing parts of the thyroid gland.
22
Q
Explain why acetaldehyde is toxic to the liver, and explain what this can lead to.
A
Toxic to hepatocytes:
- Decreases the conjugation and removal of bilirubin, leading to jaundice.
- Decreased albumin and clotting factor production.
- Decreased urea production.
- Loss of ALT and AST.
23
Q
Ehler’s Danlos Syndrome is due to a deficiency in which enzyme?
A
Lysyl oxidase.
24
Q
What is the inheritance pattern in G6PD deficiency?
A
X-linked recessive.
25
Why are red blood cells particularly affected by a G6PD deficiency?
The pentose-phosphate pathway is their only source of NADPH as they do not contain mitochondria.
26
Explain how base-excision repair occurs.
Deaminating of a cytosine base to a uracil is detected by DNA polymerase.
The uracil is removed, leaving a base-less DNA backbone.
The correct base is filled by DNA polymerase.
The gaps are sealed by DNA ligase.
27
When does nucleotide excision repair, occur?
When there is dimerisation of thymine bases, due to UV radiation damage.
28
What is the gene and inheritance pattern of Marfan’s syndrome?
Fibrillin-1 gene.
Autosomal dominant.
29
What is the inheritance pattern of cystic fibrosis?
Autosomal recessive.
30
What are some commonly used treatments for myasthenia gravis?
Acetylcholine esterase inhibitors.
Immunosuppressive drugs.
31
What is the ion channel affected in cystic fibrosis?
Cystic fibrosis transmembrane conductance regulator.
32
Where is fructose metabolised in the body?
In the liver.
33
What enzyme is deficient in fructose intolerance?
Aldolase.
34
Who is affected most by Alport syndrome and what symptoms do they have?
Males, who have:
- Blood and protein in the urine.
- Renal failure.
- Neural deafness and eye disorders.
35
What is the inheritance pattern of Alport syndrome?
X-linked recessive.
36
What type of collagen is defective in Alport syndrome, and why does it affect the kidney?
Type IV collagen.
It is bound in the basement membrane of the golmerular.
37
What is the function of the zona pellucida?
Prevents polyspermy of the zygote.
38
What type of G-protein is affected by the pertussis toxin?
G-alpha-i.
39
What component of a cell has capacitance?
The cell membrane/ lipid bilayer.
40
What is the inheritance pattern of achondroplasia?
Autosomal dominant.
41
What antibody is produced in Graves’ disease?
Thyroid stimulating immunoglobulin.
42
What is the most common cause of Addison’s disease? What are some other causes?
Autoimmune destruction of the adrenal cortex.
Other causes are:
- Infection with TB or fungal.
- Malignancy.
- Vascular (infarction).
- Iatrogenic; adrenalectomy or drugs.
43
What is the treatment for Addison’s disease?
Glucocorticoid and mineralocorticoid lifelong replacement.
44
What is the treatment for sickle cell anaemia?
Folic acid.
Hydroxycarbamide - increase HbF levels.
Red cell exchange.
Penicillin and vaccinations due to hyposplenism.
45
What is the clinical presentation of Klumpke’s palsy, and what spinal nerves are affected?
It is also known as ‘claw hand’:
- Hyperextension of the metacarpophalangeal joints.
- Flexion of the interphalangeal joints.
- Abduction of the thumb.
- Wasting of the interossei.
Affects spinal nerves C8 and T1.
46
What is the definition of bioavailability?
The fraction of a defined dose that makes its way into a specific body compartment.
47
What is thrombosis?
A solid mass of blood in the circulatory system.
48
What is the first-line antibiotic for clostridium difficile?
Vancomycin, orally.
49
What are the two toxins produced by clostridium difficile and what are their mechanism of action?
Toxin A - enterotoxin that causes excessive fluid secretion and stimulates an inflammatory response.
Toxin B - cytotoxin that damages protein synthesis.
50
What would the resulting position of the leg after an intracapsular neck of femur fracture?
Shortened, abducted and externally rotated.
51
Outline the synthesis of ketone bodies from fatty acids.
Fatty acids undergo beta-oxidation to synthesise acetyl-CoA.
Acetyl-CoA then gets converted to HMG-CoA by HMG-CoA synthase.
HMG-CoA is then converted to acetoacetate by HMG-CoA lyase.
52
What is dysplasia?
The abnormal maturation of cells within a tissue, that is disorganised and has the potential to become neoplastic.
53
What is the first line treatment for thrombus formation, and what is its mechanism for action?
Low molecular weight heparin.
It activated antithrombin to degrade thrombin.
54
What drug is used to treat oestrogen receptor-positive breast cancer, and what is its action?
Tamoxifen.
It binds to oestrogen receptors, preventing oestrogen from binding, preventing proliferation of the neoplasm.
55
What are the clinical implications of gestational diabetes?
Miscarriage.
Congenital malformation.
Fetal macrosomia.
Shoulder dystocia.
Gestational hypertension and preeclampsia.
56
What type of immunity do vaccinations provide?
Active artificial immunity.
57
When is the eosinophil count raised?
In allergic reactions and parasitic infections.
58
What is the X-axis and Y-axis representing on a lineweaver burk plot?
X-axis = -1/Km.
Y-axis = 1/Vmax.
59
Describe the process of fracture healing.
60
What is the name of the pre-embryonic cell accumulation that implants, first?
Conceptus.
61
What occurs in the 3rd week after fertilisation, and what is the structural feature?
Gastrulation.
This is the formation of the a trilaminar disc, containing the ectoderm, mesoderm and endoderm.
62
What is the definition of peripheral oedema?
An accumulation of fluid in the interstitial space of the arms and legs, causing swelling.
63
Which sensory structures in the skin transmit pain signals?
Free nerve endings.
Nociceptors in the epidermis.
64
What are the two names for growth that occurs in flat bones?
Intra-membranous ossification.
Interstitial growth.
65
Where are the metaphysis located in children?
Just below the growth plates of long bones.
66
What symptoms are associated with Duchene muscular dystrophy?
Weakened and wasting of skeletal muscle.
Loss of sensation in the limbs.
Shoulders and arms held back when walking.
Sway back.
Abdominal distension and inability to perform sit-ups.
Thin, weak thighs.
Poor balance.
Walking on toes and thick calf muscles.
Backwards bending of the knees.
67
Explain the sequence of events of the sliding filament theory.
68
What are the functions of troponin I and troponin T?
Troponin I - binds to F-actin to hold the troponin-tropomyosin complex in place, and prevents contraction.
Troponin T - binds to tropomyosin, forming the troponin-tropomyosin complex.
69
What type of bonds are non-competitive inhibitors likely to form with enzymes?
Non-covalent bonds:
- Hydrogen bonds.
- Hydrophobic interactions.
- Ionic bonds.
- Electrostatic interactions.
70
What are disulphide bonds, and what are they broken by?
They are covalent bonds formed between two SH groups, of cysteine amino acid residues.
They are broken with reducing agents.
71
What type of amino acid residues likely to span the cell membrane in transmembrane domains, and why?
Hydrophobic amino acid residues.
This is because they are able to form hydrophobic interactions with the lipid bilayer.
72
What is trimorbidity?
Combination of physical and mental ill health, and drug or alcohol abuse.
73
What is a PROM?
A patient-reported outcome measure, where patients’ well-being is self-reported, usually through questionnaires.
74
What is stigma?
Identification and recognition of a negatively defined condition, attribute, trait or behaviour in a person.
75
What is the index of multiple deprivation?
A commonly-used measure of social deprivation, calculated at the level of geographical residence.
76
What is cultural competence?
The ability to provide care for patients with diverse values, beliefs and behaviours.
77
What is the most common structural heart defect seen in endocarditis?
Tricuspid valve regurgitation.
78
What is the recommended antibiotic for MRSA?
Vancomycin.
79
What is the gram stain of clostridium difficile?
Gram-positive bacillus.
80
What virulence factor is most important of E. Coli’s, regarding urinary tract infections?
The adhesins on fimbriae.
81
How can statistical significance be shown with a confidence interval?
If it is a rate ratio and the confidence interval does not include 1, then it is statistically significant.
If it is an absolute difference and the confidence interval does not include 0, then it is statistically significant.
82
What is responder bias?
When somebody deliberately decides to withhold information for a reason.
83
What is the hallmark for an analytical epidemiological study?
Use of an appropriate comparison group.
84
What is reporting bias?
When a paper is rewritten to form a statistical significance.
85
What is population health?
An approach to health that aims to improve the health of an entire population.
86
What is the standard running speed of an ECG, and what is the length of time for 1 small square?
25mm/s.
1 small square = 0.04s or 40ms.
87
In which week of development does the embryo fold?
4th.
88
Where does the embryo move the cardiogenic field in the 4th week of development?
It moves it caudal into the oropharyngeal membrane.
89
What do the fossa ovale and ductus arteriosus become after birth?
Fossa ovalis.
Ligamentum arteriosum.
90
What channel type is responsible for the upstroke of the action potential in pacemaker cells?
Voltage-gated calcium channel.
91
What is the effect of severe hyperkalaemia on the spread of action potentials though out the myocardium?
Cardiac myocytes depolarise, inactivating the voltage-gated sodium channels, slowing down the spread of action potentials.
92
Paramedics arrive on the scene to find a young man lying unconscious in a large pool of blood. He has sustained a stab wound to the groin. On assessment they determine that he is in hypovolaemic shock. What do you think the state his arterial blood pressure (aBP), central venous pressure (CVP) and peripheral resistance (TPR) will be?
aBP = decrease.
TPR = increase.
CVP = decrease.
93
What are the left, right and inferior borders of the heart?
Left = left ventricle.
Right = right atrium.
Inferior = right ventricle (and some left ventricle).
94
Why may the heart shadow become enlarged?
Left ventricular hypertrophy.
Left ventricular dilation.
Pericardial effusion.
95
What do the chordae tendinae attach to on the left and right side of the heart?
The papillary muscles to the mitral valve on the left.
The papillary muscles to the tricuspid valve on the right.
96
What long term impact would a large ventricular septal defect have on the pulmonary circulation if left untreated?
Increased pressure can damage the pulmonary vascular use, leading to vascular remodelling, where there is hypertrophy of the smooth muscle in the tunica media of the pulmonary artery. There will be increased pulmonary resistance.
97
What causes the valves between the atria and ventricles to close?
A small backflow of the blood as the ventricles contract.
98
What structures does the transverse pericardial sinus separate?
The pulmonary trunk and aorta, from the venous inflow to the heart.
99
How does adenosine work to terminate a supraventricular tachycardia arising from a re-entry pathway?
Slows/ momentarily blocks the AV node conduction.
100
How would a first degree heart block appear on an ECG trace?
Prolonged PR interval.
101
What is the abnormality seen in leads V1 and V2?
Pathological Q waves.
102
What can cause tall R waves in leads V5 and V6?
Left ventricular hypertrophy.
103
Why may there be inversion of only 1 QRS complex on an ECG?
Ectopic ventricular beat.
104
What does the following ECG indicate?
Atrial fibrillation.
105
Which ventricle depolarises first in bundle branch block?
The unaffected ventricle.
106
What is the QRS appearance of an ECG with a bundle branch block?
Broad QRS complex.
107
Which leads are used in diagnosing bundle branch blocks, and why?
Chest leads, as they register movements in a horizontal plane.
108
Which is there normally a small negative deflection in V6 and positive deflection in V1?
The electrical impulse moves from left to right ventricles.
109
What is the appearance of V1 and V6 in RBBB?
V6 is normal, but a slightly longer ‘s’ wave.
V1 has the initial positive deflection, a small negative deflection BUT then a large positive deflection, giving an M shape.
110
What is the appearance of V1 and V6 in LBBB, and why?
The depolarisation spread from left to right is reversed, moving from right to left.
This means that V6 has an initial positive deflection, a small downward and then large upward deflection, giving an M shape.
V1 has an initial negative deflection, then a small upward deflection and then a large negative deflection.
111
What is the length, surface area, pH and transit time of the small intestine?
Length = 6-7m.
Surface area = 30-35m^2.
pH = 6-7.
Transit time = 3-5 hours.
112
What are the 3 mechanisms that inducers use to increase expression of CYP450s?
Increased gene transcription.
Increased mRNA translation.
Decreased degradation.
113
What are the 3 processes of drug movement in the kidney?
Glomerular filtration.
Active tubular secretion.
Passive tubular reabsorption.
114
What are the 3 excitatory, 2 inhibitory and the mixed neurotransmitter, that act as paracrine molecules?
3 excitatory = noradrenaline, serotonin and glutamate.
2 inhibitory = GABA and glycine.
Mixed = dopamine.
115
What is the primary inhibitory neurotransmitter in the CNS and spinal cord?
CNS = GABA.
Spinal cord = glycine.
116
How does the mechanism of herceptin aid in the treatment of breast cancer?
Non-competitively binds to HER2, tyrosine kinase receptors.
Inhibits dimerisation and growth factor signals, preventing proliferation.
117
Outline the different structural components of nuclear receptors.
118
What types of molecules bind to receptor kinases, and how long do they last?
Peptide and protein.
A few minutes to hours.
119
How does Lamotrigine work?
Prolongs the duration of the VGSC in the inactivated state, reducing the firing activity in highly depolarised CNS neurones.
120
Which drug increases PT and is monitored by regular INR measurements?
Warfarin.
121
What can cause coagulative necrosis of the liver?
Infarction/ ischaemia.
Chemical injury.
122
What are abdominal adhesions?
Bands of fibrous tissue that form between abdominal tissues and organs.
123
Why do scars become stretched?
Elastic fibres do not regenerate.
124
What factors can cause poor wound healing?
Diabetes.
Obesity.
Nutritional/ vitamin deficiency.
Infection of the wound.
Steroidal treatment.
125
What diseases can cause granulation tissue?
Sarcoidosis.
Tuberculosis.
Aspergillosis.
Syphilis.
Crohn’s disease.
126
What can accumulate in hepatocytes in patients who drink excess alcohol?
Fat.
Mallroy’s hyaline.
127
What type of neoplasm is most frequently seen to produce PTH-like peptides?
Bronchial squamous cell carcinoma.
128
What is the most common type of cervical cancer?
Squamous cell carcinoma.
129
State the 8 tumour markers we have been taught about.
Human chorionic gonadotropin.
Calcitonin.
Catecholamine and metabolites.
Alpha-fetoprotein.
Carcinoembryonic antigen.
Prostate-specific antigen.
CA-125.
CA-19-9.
130
What are the associated cancers for human chorionic gonadotropin?
Trophoblasts tumours.
Non-seminoma testicular tumours.
131
What is the associated cancer for calcitonin?
Medullary carcinoma of the thyroid.
132
What is the associated cancer for catecholamines?
Phaeochromocytoma.
133
What is the associated cancer for alpha-fetoprotein?
Liver cell cancer.
Non-seminoma germ cell tumours of the testes.
134
What is the marker carcinoembryonic antigen associated with?
Colon cancer.
135
What cancer is prostate-specific antigen associated with?
Prostate cancer.
136
What is the marker CA-125 associated with?
Ovarian cancer.
137
What is the marker CA-19-9 associated with?
Pancreatic cancer.
138
What is the progression of cancer names in the adenoma-carcinoma sequence of the colon?
Early adenoma - intermediate adenoma - late adenoma - primary carcinoma - metastatic carcinoma.
139
How does metaplasia occur?
There is stimulation of stem cells to express different genes, leading to the replacement of one terminally differentiated cell for another terminally differentiated cell.
140
How does thrombus differ from clotting?
Thrombus formation is in the circulatory system, whereas clotting is outside.
Thrombus is pathological, whereas clotting is physiological.
141
What are the principal cells of granulation tissue?
Fibroblasts and myofibroblasts.
Endothelial cells.
142
What type of necrosis is seen in tuberculosis?
Caseous necrosis.
143
What is the mutation and symptoms seen in inherited angio-oedema?
Mutation, causing the absence of C1 esterase inhibitor.
Symptoms:
- Shortness of breath and sudden death due to laryngeal oedema.
- Abdominal pain due to intestinal oedema.
- Swelling of the skin due to oedema.
144
What nerves are associated with the thyroid gland, and are at risk with thyroid surgery?
Recurrent and superior laryngeal nerves.
145
What do MIT, DIT, T3 and T4 stand for?
MIT = monoiodotyrosine.
DIT = diiodotyrosine.
T3 = triiodothyronine.
T4 = tetraiodothyronine - thyroxine.
146
What does thyroid peroxidase require to oxidise iodide to iodine?
Hydrogen peroxide.
147
What GPCRs can TSH act on?
Alpha-s or alpha-q.
148
How do thyroid hormones increase the sensitivity for catecholamines?
They increase the receptor numbers on target cells.
149
What are the two types of neuromuscular relaxants, used in surgery?
Depolarising.
Non-depolarising.
150
What are the lengths of the absolute and relative refractory periods?
Absolute = 1 second.
Relative = 4 seconds.
151
What how does diazepam exert its effects?
As a positive allosteric modulator.
152
How does flumazenil work as treatment for diazepam overdoses?
It competitively inhibits the binding site for diazepam.
153
How does GABA exert its effects?
It binds to GABA receptors, activating the channel, allowing an influx of chloride ions, hyperpolarising the membrane.
154
How are GABAs effects stopped?
Re-uptake by co-transport with sodium via the GABA transporter.
155
What are the 3 physiological factors determining a resting membrane potential?
The concentrations of ions inside and outside the cell membrane.
Permeability of the ions.
Electrogenic pump activity.
156
What type of cell adherence do motile cells not contain?
Gap junctions.
157
What does the psychosocial explanation state?
That health inequalities are due to differences in incomes, as opposed to the incomes themselves.
158
When does fertilisation normally occur?
Fertilisation occurs during ovulation, which is 14 days after the last menstrual period date.
159
What type of epithelium is found lining the oesophagus?
Stratified squamous non-keratinised.
160
What enzyme converts HMG-CoA to cholesterol?
HMG-CoA reductase.
161
What effect does calcitonin have on the gastrointestinal tract?
No effect.
162
What bacteria is commonly found in the mouth?
What is its gram stain and description?
Streptococcus mutants.
It is an anaerobic gram-positive bacteria.
163
What type of hypoxia is carbon monoxide poisoning?
Anaemia hypoxia - decreased ability of haemoglobin to carry oxygen.
164
What type of hypoxia is cyanide poisoning?
Histiocytic - cells cannot utilise the oxygen.
165
What type of hypoxia can COPD, with a low oxygen content cause?
Hypoxaemic hypoxia.
166
What type of hypoxia can a blockage in a vessel be classed as?
Ischaemic hypoxia.
