Mock Questions Flashcards
State 3 anabolic processes that the TCA cycle provides precursors for.
Amino acid synthesis.
Haem synthesis.
Fatty acid synthesis.
Glucose synthesis.
Name 3 cardiac defects that lead to left to right shunts.
Ventricular septal defect.
Atrial septal defect.
Patent ductus arteriosus.
What type of tissue are benign adenomas of the colon formed from?
Glandular epithelial tissue.
What can cause tumourigenesis?
Smoking.
Alcohol consumption.
Diet.
Obesity.
Human papilloma virus.
Epstein Barr virus.
UV radiation from the sun.
Ionising radiation.
What oxygen saturation should oxygen be given for?
Anything below 92%.
What is the scoring system used to determine the likelihood of DVT?
Wells’ score/ criteria.
Explain how paracetamol overdose can cause liver damage.
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.
Define the term homeostasis.
The control of the internal environment within set limits via a dynamic equilibrium.
What is BMR and what factors can affect BMR?
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.
What is meant by health inequalities?
The unfair or avoidable differences in life expectancy, mortality, morbidity and disability between groups within the same population.
State the social determinants of health inequalities.
Social class.
Age.
Gender.
Ethnicity.
Disability.
Homelessness.
Deprivation.
Where is the left aortic sinus located?
Above the left leaflet of the aortic valve.
What bacteria commonly cause community-acquired pneumonia?
Streptococcus pneumoniae.
Haemophilus influenzae.
Staphylococcus aureus.
Mycoplasma pneumoniae.
Chlamydophilia pneumoniae.
What is the purpose of lactate production?
Oxide NADH back to NAD+.
Allow energy production in cells with no mitochondria.
Precursor for gluconeogenesis.
Maintain energy production in low oxygen availability.
Explain how lactate is used in the body.
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.
What are muscle cramps caused by?
Acidosis.
What molecules can cause metabolic acidosis?
Ketone bodies - acetoacetate, beta-hydroxybutyrate.
Pyruvate.
Fatty acids.
Amino acids.
ATP.
What is the function of dystrophin?
Links the cytoskeleton to the plasma membrane.
It acts as a shock absorber.
It stabilises the muscle, mechanically.
Regulates calcium levels.
Why is embryogenesis classed as mitosis?
They are somatic cells.
What does the autoantibody in Graves’ disease act on?
TSH receptors.
What are 3 ways of treating patients with Graves’ disease?
Carbimazole - inhibits thyroid peroxidase.
Radioactive iodine - destroys the glandular cells, decreasing thyroid production.
Surgical intervention - removing parts of the thyroid gland.
Explain why acetaldehyde is toxic to the liver, and explain what this can lead to.
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.
Ehler’s Danlos Syndrome is due to a deficiency in which enzyme?
Lysyl oxidase.
What is the inheritance pattern in G6PD deficiency?
X-linked recessive.
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.
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.
When does nucleotide excision repair, occur?
When there is dimerisation of thymine bases, due to UV radiation damage.
What is the gene and inheritance pattern of Marfan’s syndrome?
Fibrillin-1 gene.
Autosomal dominant.
What is the inheritance pattern of cystic fibrosis?
Autosomal recessive.
What are some commonly used treatments for myasthenia gravis?
Acetylcholine esterase inhibitors.
Immunosuppressive drugs.
What is the ion channel affected in cystic fibrosis?
Cystic fibrosis transmembrane conductance regulator.
Where is fructose metabolised in the body?
In the liver.
What enzyme is deficient in fructose intolerance?
Aldolase.
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.
What is the inheritance pattern of Alport syndrome?
X-linked recessive.
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.
What is the function of the zona pellucida?
Prevents polyspermy of the zygote.
What type of G-protein is affected by the pertussis toxin?
G-alpha-i.
What component of a cell has capacitance?
The cell membrane/ lipid bilayer.
What is the inheritance pattern of achondroplasia?
Autosomal dominant.
What antibody is produced in Graves’ disease?
Thyroid stimulating immunoglobulin.
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.
What is the treatment for Addison’s disease?
Glucocorticoid and mineralocorticoid lifelong replacement.
What is the treatment for sickle cell anaemia?
Folic acid.
Hydroxycarbamide - increase HbF levels.
Red cell exchange.
Penicillin and vaccinations due to hyposplenism.
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.
What is the definition of bioavailability?
The fraction of a defined dose that makes its way into a specific body compartment.
What is thrombosis?
A solid mass of blood in the circulatory system.
What is the first-line antibiotic for clostridium difficile?
Vancomycin, orally.
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.
What would the resulting position of the leg after an intracapsular neck of femur fracture?
Shortened, abducted and externally rotated.
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.
What is dysplasia?
The abnormal maturation of cells within a tissue, that is disorganised and has the potential to become neoplastic.
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.
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.
What are the clinical implications of gestational diabetes?
Miscarriage.
Congenital malformation.
Fetal macrosomia.
Shoulder dystocia.
Gestational hypertension and preeclampsia.
What type of immunity do vaccinations provide?
Active artificial immunity.
When is the eosinophil count raised?
In allergic reactions and parasitic infections.
What is the X-axis and Y-axis representing on a lineweaver burk plot?
X-axis = -1/Km.
Y-axis = 1/Vmax.
Describe the process of fracture healing.
What is the name of the pre-embryonic cell accumulation that implants, first?
Conceptus.
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.
What is the definition of peripheral oedema?
An accumulation of fluid in the interstitial space of the arms and legs, causing swelling.
Which sensory structures in the skin transmit pain signals?
Free nerve endings.
Nociceptors in the epidermis.
What are the two names for growth that occurs in flat bones?
Intra-membranous ossification.
Interstitial growth.
Where are the metaphysis located in children?
Just below the growth plates of long bones.
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.