Co-ordination and Control Flashcards
Cells can respond to signals by modulating the activity of…? A) Genes B) Ribosomes C) Enzymes D) The cytoskeleton E) All the above
E) All of the above
Turning genes on and off is important because it? A) Increases cellular metabolism B) Changes protein expression C) Triggers cell division D) Protects cells from apoptosis E) Releases second messengers
B) Changes protein expression
What 2 would you analyse to see which genes are up-regulated and down-regulated by testosterone. A) DNA B) RNA C) Proteins D) Second messengers E) Lipids
B) RNA
C) Proteins
What proportion of your genes codes for a GPCR? A) 1 in 20 B) 1 in 100 C) 1 in 1,000 D) 1 in 10,000 E) 1 in 100,000
A) 1 in 20
How do we know how many different GPCRs humans have? A) Genome sequencing B) RNA sequencing C) Ligand binding studies D) Western blotting E) Phosphorylation analysis
A) Genome sequencing
What would you expect to happen if you added a GaS specific GTPase inhibitor to these Leydig cells? A) Nothing B) Increased testosterone production C) Decreased testosterone production D) Decreased AMP concentration E) Decreased ligand binding affinity
B) Increased testosterone production
What is a feature of a second messenger system? A) Can cross cell membranes B) Specificity of signal C) Amplification of signal D) Binds DNA directly E) Triggers apoptosis
C) Amplification of signal
What does a kinase do? A) Adds phosphate to things B) Stimulates translocation of things C) Cleaves things D) Links things E) Removes polysaccharides from things
A) Adds phosphate to things
What effects does phosphorylation have on the target protein?
A) Stimulates its activity
B) Represses its activity of things
C) Provides a binding site for other proteins
D) Triggers degradation
E) Changes its charge
ALL
An effective cyclin B dependent kinase inhibitor would inhibit what? A) DNA replication B) Receptor phosphorylation C) Mitosis D) Retinoblastoma phosphorylation E) E2F activity
C) Mitosis
If someone injures their head and loses vision in the left field, what brain region is damaged? A) Left Parential Lobe B) Right Parential lobe C) Left occipital lobe D) Right occipital lobe E) Left optic nerve
D) Right occipital lobe
Which part of the peripheral nervous system is responsible for control of skeletal muscle contraction? A) Sympathetic B) Parasympathetic C) Enteric D) Somatic
D) Somatic
The movement of which ion initially depolarises the membrane to activate Ca2+ channels? A) Calcium B) Chloride C) Magnesium D) Potassium E) Sodium
E) Sodium
What type of receptor is the nicotinic acetylcholine receptor? A) A voltage-gated ion channel B) A metabotropic receptor C) An enzyme-linked receptor D) An ionotropic receptor
D) An ionotropic receptor
Which neurotransmitter is used in the post-ganglionic sympathetic innervation of sweat glands in the skin? A) Noradrenaline B) Acetylcholine C) Dopamine D) Glycine E) Serotonin
B) Acetylcholine
Adrenaline is central to the ‘fight or flight’ response. Which of the following isNOT a response to adrenaline? A) Bronchodilation B) Bronchoconstriction C) Smooth muscle contraction D) Smooth muscle relaxation
B) Bronchoconstriction
Which of these could be used to treat myasthenia gravis?
A) Choline acetyltransferase inhibitors
B) SNARE inhibitors
C) Nicotinic acetylcholine receptor inhibitors
D) Acetylcholine esterase inhibitors
D) Acetylcholine esterase inhibitors
From which amino acid are catecholamine neuro-transmitters derived? A) Lysine B) Glutamate C) Glycine D) Tryptophan E) Tyrosine
E) Tyrosine
Identify the sequence of some key events that occur during action potentials, where 1= depolarisation, 2= hyperpolarisation, 3= repolarisation, 4= potassium ion exit, 5= sodium ion entry:
A. 1 5 2 3 4 B. 4 1 2 5 3 C. 5 1 4 3 2 D. 5 2 3 4 1 E. 5 3 4 1 2
Answer: C
Learning Point: Action potential physiology
- Botulinum toxin interferes with neuronal signalling by blocking exocytosis.
What type of biological molecule is normally released in this situation?
A. Neurotransmitter B. Peptide hormone C. Phospholipid D. Prostaglandin E. Steroid hormone
Answer: A
Learning point: toxins and the SNARE hypothesis
- A 65 year old man is diagnosed with bladder cancer. Analysis of DNA from the tumour cells shows a mutation in the ras GTPase oncogene. This mutation locks the Ras protein into a state where it permanently binds GTP.
What effect does this have on the Ras protein?
A. It is inactivated B. It is constitutively activated C. It is degraded D. It is dephosphorylated E. It translocates to the nucleus
Answer: B
Learning point: oncogenes
The movement of which ion initially depolarises the membrane to activate Ca2+ channels?
A. Calcium B. Chloride C. Hydrogen D. Potassium E. Sodium
Answer: E
Learning point: physiology of neurotransmission
- Parkinson’s disease is a neurological condition, characterised by hypokinesia (diminished motor function), tremor and muscular rigidity.
L-DOPA is used to treat this disease because?
A. Dopamine does not cross the blood-brain barrier
B. L-DOPA evokes dopamine release
C. L-DOPA selectively antagonises enzymes which inactivate dopamine
D. The chemical synthesis of dopamine is uneconomic
E. The effects of L-DOPA are longer lasting than those of dopamine
Answer: A
- You are working for a pharmaceutical company. You are screening a batch of novel G protein-coupled receptor agonists and note that one compound, PCMD101, is labelled as Gαq specific?
Measuring the production of which of the following would enable you to estimate the activity of this compound?
A. ATP B. Cyclic AMP C. Intracellular adenosine D. Intracellular Ca2+ E. Tyrosine kinase
Answer: D
