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Explain how a synapse between two neurons functions

When impulse arrives at pre-synaptic terminal, the depolarisation opens the voltage-gated Ca2+ ion channels. This causes Ca2+ to enter synapse due to differences in concentration. This causes the vesicles...

Answered by George B. • Biology tutor

2718 Views

What is the subjunctive and how do I form it?

The Spanish subjunctive is a "MOOD" which means it reflects the attitude or the feelings of the person who is speaking. You can have a subjunctive mood in different verb tenses (subjunctive pres...

Answered by Emma T. • Spanish tutor

2462 Views

Why do I sometimes say 'ich fahre in der Stadt' and other times 'ich fahre in die Stadt'? What is the difference and why is there one?

Here, the difference is not between gender: 'Stadt' is always a feminine noun. Here, 'in der Stadt' is in the dative case, governed by the preposition 'in', whilst 'in die Stadt' is in the accusative. 'In...

Answered by Melissa M. • German tutor

12972 Views

Describe a test that could be used to distinguish between potassium sulfate (K2SO4) and potassium nitrate (KNO3)

Add a solution containing Barium ions (eg BaCl2, Ba(OH)2, etc)K2SO4 will form white precipitateKNO3 will have no visible change

Answered by Isobel W. • Chemistry tutor

15055 Views

An aldehyde CH3CH2CH2CHO reacts with potassium cyanide (KCN) to form a racemic mixture of two stereoisomers of CH3CH2CH2CH(OH)CN. A)Explain why a racemic mixture is formed and b)describe how you would distinguish between 2 samples of the stereoisomers

A) The aldehyde contains a planar carbon group which can be attacked from both sides. Each side has equal probability of being attacked resulting in a ra...

Answered by Isobel W. • Chemistry tutor

8209 Views