Restriction fragment length polymorphism denotes that a single restriction enzyme produces fragments of different lengths from the same stretch of genomic DNA of different strains of a species or from different related species. RFLPs are detected as follows:

i.  Large molecular weight genomic DNA is isolated from several strains or related species;

ii.  The fragments in these digests are separated through electrophoresis

iii.  These 'DNAs are then digested with a selected restriction enzyme

iv.  Exposed to a suitably radio-labelled appropriate DNA probe under conditions favouring DNA: DNA hybridization

v.  The resulting gel lanes are transferred and fixed to a suitable solid support and

vi.   The free probes are removed

vii.  The fragments to which the probe has hybridized are detected by filming them as distinct bands on a suitable photofilm through autoradiography.

#Question id: 11211

#Unit 7. System Physiology – Animal

The following steps refer to various stages in transmission at a chemical synapse.

1. Neurotransmitter binds with receptors associated with the postsynaptic membrane.

2. Calcium ions rush into neuron's cytoplasm.

3. An action potential depolarizes the membrane of the presynaptic axon terminal.

4. The ligand-gated ion channels open.

5. The synaptic vesicles release neurotransmitter into the synaptic cleft.

Which sequence of events is correct?

#Question id: 11212

#Unit 7. System Physiology – Animal

The activity of acetylcholine in a synapse is terminated by its ________.

#Question id: 11213

#Unit 7. System Physiology – Animal

An example of ligand-gated ion channels is ________.

#Question id: 11214

#Unit 7. System Physiology – Animal

Neurotransmitters categorized as inhibitory are expected to ________.

#Question id: 11215

#Unit 7. System Physiology – Animal

If excitatory postsynaptic potentials (EPSPs) are produced nearly simultaneously through two different synapses on the same postsynaptic neuron, the EPSPs can also add together creating ________.

#Question id: 11216

#Unit 7. System Physiology – Animal

When two excitatory postsynaptic potentials (EPSPs) occur at a single synapse so rapidly in succession that the postsynaptic neuron's membrane potential has not returned to the resting potential before the second EPSP arrives, the EPSPs add together producing ________.