Question 1
Question
Which features of ionising radiation is incorrect?
Answer
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X/gamma rays have energy to break bonds.
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Damage to DNA bases.
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Water is the main target for ionising radiation.
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Water breaks into H and OH radical with OH and ionising radiation go on to break DNA strands.
Question 2
Question
What are all the effects of death of endothelial cells
Question 3
Question
Which is not a feature of UV radiation to damage of DNA?
Answer
-
Damage to DNA bases where adjacent C-T become linked.
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The DNA strand will break.
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Misrepair generates C to T point mutations leading to cancer development
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More damage leads to death of keratinocytes (peeling sunburn)
Question 4
Question
The chemical factor to damage to DNA -Alkylation is:
Answer
-
Fungal product aflatoxin B1 accumulates in poorly stored food (in underdeveloped countries).
-
Metabolites react covalently (alkylate) with proteins to cause liver injury ; acutely at high doses.
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Metabolites alkylate DNA hence G to T mutations = liver cancer= chronic and low doses.
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Folic acid further damages the DNA.
-
The crystals puncture the membranes.
Question 5
Question
Which is a feature of biological dietary deficiency - DNA?
Answer
-
Autoimmune gastritis lack intrinsic factor prevents B12 absorption.
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Proteins cause liver injury acutely
-
Inflammasomes generate severe inflammation.
-
Hydrogen peroxide will be detoxifed to catalase to oxygen and water.
Question 6
Question
Which is not a feature of chemical damage to lipids?
Answer
-
Cells take up crystals into lysosomes.
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Crystals puncture lysosome membrane.
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Damaged mitochondria cannot reduce oxygen completely.
-
Inflammasomes activated.
Question 7
Question
ROS and RNS are not free radicals?
Question 8
Question
Which is not an oxidative reaction in the chemical factor of damage to lipids?
Answer
-
Superoxide (O2-) - detoxed by superoxide dismutase
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Hydrogen peroxide - detoxed by catalase
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Oxygen therapy - exposure to premature babies
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Hydroxyl radical - OH.
Question 9
Question
Which of these does not contribute to injury of cell via ROS?
Answer
-
Oxygen therapy
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Inflammation
-
Megablastic anaemia
-
Damaged mitochondria
-
UV radiation
-
Radiotherapy
Question 10
Question
How does acute haemorrhagic pancreatitis occur?
Biological lipase factor
Answer
-
Proteolytic cleavage of ECM proteins
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The p53 transcription factor
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Damage to exocrine cells which synthesise digestive enzymes or block ducts that these enzymes travel to duodenum by
-
Prolonged heat exposure
Question 11
Question
Which is not a consequence of heat exposure in proteins?
Question 12
Question
Is the Maillard reaction the enzymatic addition of sugars to proteins?
Question 13
Question
Which of the following is not a result of the reaction occurring between reducing sugars and amino groups?
Answer
-
Reversible early stage Schiff bases
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Irreversible rearrangements to Amadori products.
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Further rearrangements to advanced glycation end products (AGE).
-
Nrf transcription factors.
Question 14
Question
How do AGE injure cells?
Answer
-
Inhibit protein function
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Cross linking and precipitating proteins (blocking axon transport in neurons)
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Generating ROS
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Binding to receptors of AGE (RAGE) on vascular and inflammatory cells that reduce blood flow and cause inflammation.
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The enzymatic addition of sugars to proteins.
Question 15
Question
Does AGE accumulate during ageing, diabetes, and chronic inflammation?
Question 16
Question
When and where does proteolytic cleavage occur during inflammation when proteins are damaged?
Biological factor
Question 17
Question
Which factor does acute intracellular oedema (hydropic change) not affect the cells regulation of ion concentration in cytoplasm?
Answer
-
Plasma membranes permeable to Na+ hence K+ leaks out (Na+ in) hence cell swells.
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ATP synthesis disrupted, Na+/K+ ATPase inhibited
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Na+ pump damaged
-
Cell shrinks due to excess water loss
Question 18
Question
Does abnormalities in capacity of cells to recycle components result in the non-accumulation of products such as fat and glycogen?
Question 19
Question
When there are fatty changes in liver cell what does not happen when the triglycerides accumulate?
Answer
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In normal liver cells they cannot metabolise increased fatty acids conc. coming from adipose tissue (diabetes)
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In abnormal liver cells they have a decreased ability to oxidise fatty acids (alcohol damage)
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In abnormal liver cells have decreased ability to export triglycerides compounded with lipid-acceptor proteins i.e. VLDL leading to malnutrition, kwashiorkor - not enough proteins and more fat.
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In normal liver cells they cannot transport more of the fat from the tissue to urine and therefore leading to blockage.