Formative Flashcards
Energetically unfavourable reactions can only proceed because they:
a) are coupled to anabolic reactions
b) are coupled to catabolic reactions
c) are spontaneous
d) have negative free energy changes
e) release energy into the universe
b) are coupled to catabolic reactions
Which one of the following correctly describes a nucleotide?
a) base + ribose sugar + nucleoside
b) base + ribose sugar + phosphate
c) phosphate + base
d) phosphate + deoxyribose sugar
e) phosphate + ribose sugar
b) base + ribose sugar + phosphate
The lipid membrane surrounding eukaryotic cells does not contain:
a) carbohydrates
b) cholesterol
c) ion channels
d) receptors
e) ribosomes
e) ribosomes
The dissociation constant for water is:
a) 1x10^-1 (mol/L)^2
b) 1x10^-4 (mol/L)^2
c) 1x10^-7 (mol/L)^2
d) 1x10^-12 (mol/L)^2
e) 1x10^-14 (mol/L)^2
e) 1x10^-14 (mol/L)^2
Amino acid sequence is described as the ___________ structure of a protein:
a) primary
b) quaternary
c) secondary
d) tertiary
e) unordered
a) primary
An enzyme increases the rate of a spontaneous reaction by:
a) changing conformation
b) decreasing the activation energy
c) increasing the activation energy
d) increasing ΔG
e) moving the reaction equilibrium
b) decreasing the activation energy
Monomers of carbohydrates are linked together by:
a) gluconeogenic bonds
b) glycosidic bonds
c) ionic bonds
d) peptide bonds
e) phosphodiester bonds
b) glycosidic bonds
Catabolism of 1 mol of glucose to lactate generates how many net moles of ATP?
a) 1
b) 2
c) 3
d) 4
e) 36
b) 2
Ingesting alcohol reduces which one of the following intermediates, particularly in the liver?
a) ATP
b) NAD+
c) NADH
d) NADP+
e) NADPH
b) NAD+
What is the name of the molecule that transports electrons between complexes III and IV of the electron transport chain?
a) coenzyme Q10
b) cytochrome B
c) cytochrome C
d) ubiquinone
e) ubiquinol
c) cytochrome C
ATPase utilises which one of the following mechanisms in order to generate ATP?
a) binding-change mechanism
b) binding-sequence mechanism
c) binding-site mechanism
d) bonding-change mechanism
e) bonding-site mechanism
a) binding-change mechanism
Which one of the following vitamins is not derived from a lipid?
a) vitamin A
b) vitamin C
c) vitamin D
d) vitamin E
e) vitamin K
b) vitamin C
Excess acetyl CoA from fatty acids gives rise to the formation of:
a) citrate
b) glucose
c) glucose-6 phosphate
d) ketones
e) oxaloacetate
d) ketones
Which amino acid is central to nitrogen entering the body?
a) alanine
b) glutamate
c) proline
d) threonine
e) tryptophan
b) glutamate
Which one of the following cycles is important in nitrogen metabolism?
a) glucose-alanine cycle
b) glucose-carnitine cycle
c) glucose-cori cycle
d) glucose-phosphate cycle
e) glucose-pyruvate cycle
a) glucose-alanine cycle
If a person drinks one litre of water:
a) all will enter the extracellular fluid
b) all will enter the intracellular fluid
c) approximately 1/2 will enter the extracellular fluid and 1/2 will enter the intracellular fluid
d) approximately 1/3 will enter the extracellular fluid and 2/3 will enter the intracellular fluid
e) approximately 2/3 will enter the extracellular fluid and 1/3 will enter the intracellular fluid
d) approximately 1/3 will enter the extracellular fluid and 2/3 will enter the intracellular fluid
Red blood cells will shrink if they are placed in a solution of:
a) 0 mM urea and 150 mM NaCl
b) 30 mM urea and 170 mM NaCl
c) 100 mM urea and 100 mM NaCl
d) 200 mM urea and 50 mM NaCl
e) 400 mM urea and 0 mM NaCl
b) 30 mM urea and 170 mM NaCl
Which of the following statements regarding epithelia is not correct?
a) A simple epithelium is one which contains cells of only one type.
b) Cilia provide a mechanism for movement of material over the surface area of epithelia.
c) Desmosomes provide a strong bond between adjacent epithelial cells.
d) Hemidesmosomes attach epithelial cells to the basement membrane.
e) Stratified epithelia have more than one layer of cells.
a) A simple epithelium is one which contains cells of only one type.
The resting membrane potential is directly generated by:
a) the Na+/K+ pump
b) the permeability of the resting membrane to Ca2+
c) the permeability of the resting membrane to Cl-
d) the permeability of the resting membrane to K+
e) the permeability of the resting membrane to Na+
d) the permeability of the resting membrane to K+
Which of the following is not an example of a graded potential?
a) action potential
b) endplate potential
c) excitatory post-synaptic potential
d) inhibitory post-synaptic potential
e) pacemaker potential
a) action potential
The endplate potential:
a) is an all-or-none event
b) is evoked in the motoneurone terminal
c) is always large enough to evoke an action potential in the muscle
d) is mediated by voltage-gated channels
e) relies on the release of Ca2+ from the sarcoplasmic reticulum
c) is always large enough to evoke an action potential in the muscle
The thick filaments of skeletal muscle are composed of:
a) actin
b) myosin
c) nebulin
d) tropomyosin
e) troponin
b) myosin
Contraction of skeletal muscle requires the:
a) binding of Ca2+ to calmodulin
b) binding of Ca2+ to myosin
c) entry of Ca2+ through ligand-gated channels
d) entry of Ca2+ through voltage-gated channels
e) release of Ca2+ from the sarcoplasmic reticulum
e) release of Ca2+ from the sarcoplasmic reticulum
An antagonist at a pharmacological receptor will have:
a) high affinity and high efficacy
b) high affinity and low efficacy
c) low affinity and high efficacy
d) low affinity and low efficacy
e) no affinity and no efficacy
b) high affinity and low efficacy
In the sympathetic nervous system:
a) preganglionic axons are generally longer than postganglionic axons
b) preganglionic cells release noradrenaline
c) spinal out flow is thoraco-lumbar
d) there is no concept of mass activation
e) the transmitter released by postganglionic cells acts on muscarinic receptors
c) spinal out flow is thoraco-lumbar
Activation of the parasympathetic system causes:
a) an increase in gut motility
b) an increase in heart rate
c) dilation of airways in the lung
d) dilation of the pupil in the eye
e) piloerection
a) an increase in gut motility
Which of the following drugs does not block transmission at the neuromuscular junction?
a) botulinum toxin
b) curare
c) hemicholinium
d) neostigmine
e) tetrodotoxin
d) neostigmine
The physiological significance of co-activation of alpha and gamma motor neurones innervating skeletal muscle is that it ensures:
a) the antagonist muscle acts in unison
b) the fast and slow fibres contract in unison
c) the muscle does not fatigue
d) the sensitivity of the muscle spindle is retained
e) there is a complete twitch contraction
d) the sensitivity of the muscle spindle is retained
Golgi tendon organs are stimulated by:
a) decreased tension and cause contraction of the muscle
b) decreased tension and cause relaxation of the muscle
c) increased tension and cause contraction of the muscle
d) increased tension and cause relaxation of the muscle
e) none of the above
d) increased tension and cause relaxation of the muscle
Viral infection would typically cause elevated levels of which blood cell type?
a) erythrocytes
b) lymphocytes
c) monocytes
d) neutrophils
e) platelets
b) lymphocytes
