ILA FORMATIVES 1 - 6 Flashcards
How is a gene sequence coded?
A gene sequences is coded in single stranded DNA
How as a promoter sequence coded?
A promotor sequence is coded in single stranded DNA
What binds to tRNA?
Specific amino acids bind to tRNA
What is the transcriptome composed of?
It is the sum total of all the messenger RNA molecule expressed from the genes of an organism
Composed of mRNA
What is alternative splicing?
Alternative splicing is a regulated process during gene expression which results in a single gene coding for multiple proteins
Particular exons mat be included or excluded form the final mRNA
What type of structure would a protein with 2 polypeptide chains held together by cross links?
Quaternary
How do cis/trans and L/D isomers differ in structure?
They are proteins that differ in their tertiary structure
What are alpha helices and beta sheets examples of?
Secondary structure
What causes sickle cell anaemia?
Sickle cells anaemia is caused by an autosomal recessive condition that substitutes an amino acid in the beta globin chain
What happens to sickle cells during hypoxia?
In hypoxia, the abnormal HbS crystallises (HHb is soluble which oxygenated and insoluble when deoxygenated) and it precipitates out and clumps in an insoluble mass
How does the genetic mutation cause sickling of the cells?
The structure change to haemoglobin causes sickling by binding to the cytoskeleton as this is what usually keeps its shape
What would cause an acute pain crisis from SS anaemia?
An acute pain crisis is typically caused by capillary occlusion in the bone
How do the sickle cells cause capillary occlusion?
The sickle cells cause capillary occlusion by binding to and activating endothelial cells causing inflammation
How can sickle cell disease be treated?
Sickle cell disease can be treated with hydroxyurea (usually an anti cancer drug an is an antimetabolite) because it increases the synthesis of foetal HbF which doesnt have a beta chain
Describe the distribution of total body water?
66% ICF
33% ECF
Of the ECF
25% Interstital fluid
8% Plasma
Give an example of insensible fluid loss?
Water from respiration
Why is oedema linked to albumin?
Because when there is low albumin, there is a decrease in oncotic pressure as so water diffuses from the blood into the interstitial fluid
Where is ADH synthesised and released?
ADH is synthesised in the hypothalamus and then released from the posterior pituitary
Where is aldosterone synthesised?
In the adrenal cortex, zona glomerulosa
Where is the principle site of renin production?
The juxtaglomerular cells
What happens when you drink water?
Your osmolality falls, so ADH secretion stops and increases urine volume
Which nerve supplies motor function to the diaphragm?
Phrenic
What supplies voluntary motor function to the larynx?
The vagus nerve
Which bronchus is more likely to have a peanut lodged in if inhaled?
Right
More vertically disposed
What would a malignant tumour of the pleural membranes be called?
A mesothelioma
What do central chemoreceptors respond to?
They are in the ventral medulla and the respond to CSF pH
Where are the main peripheral chemoreceptors located?
Carotid sinus and the aortic arch
What could cause type 1 respiratory failure?
Pulmonary embolism
What could cause type 2 pulmonary failure?
COPD
What effect would adrenaline have on the bronchi?
Bronchodilation
What do the columnar epithelial cells provide in respiratory epithelium?
Cilia for the mucocillary escalator
What secretes somatostatin?
D cells
What secretes histamines?
Enterochromaffin cells
What secretes gastrin?
G cells
What secretes pepsinogen?
Cheif cells
What is the purpose of intrinsic factors?
It allows absorption of vitamin B12 in the terminal ileum
How many muscle layers in the stomach wall?
3
What is the change in cell type seen in the lower oesophagus after prolonged acid reflux?
Stratified squamous to columnar
What does the proton pump on parietal cells do?
The proton pump on parietal cells pumps K+ into the cell and H+ out of the cell
What does the superior mesenteric artery supply?
Arterial blood to the jejunum
What is the action of omeprazole?
Inhibits the proton on parietal cells pump to reduce acid secretion
Where is fat first digested?
It is first digested by lipase enzymes in the oral cavity of the GI tract
Is the hepatic vein a part of the porta hepatis?
No
What % of cardiac output is hepatic blood supply?
25%
What is CCK released in response to?
CCK is released in response to the presence of amino acids in the gut
What commonly causes obstructive jaundice?
Obstructive jaundice is commonly caused by gallstone sin the gall bladder
Where does the pancreas lie in relation to the duodenum?
The pancreas lies in the duodenal loop
What does the microsomal enzyme Uridine Diphosphoglucuronic Transferase catalyse
The formation of conjugated bilirubin
What produces stercobilinogen?
Bacterial enzyme hydrolysis in the gut, stercobilinogen is excreted in the faeces
How is urobilinogen returned to the liver?
Enterohepatic circulation
What would an an increased serum unconjugated bilirubin and increased faecal urobilinogen cause?
Pre hepatic jaundice
What is the physiological cause of jaundice of the newborn?
Excess breakdown of foetal haemoglobin
Is Gilberts syndrome a cause of obstructive jaundice?
No
Is production of urobilinogen a function of the liver?
No
