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Explain the process of DNA replication an state why it is called semi-conservative.

During DNA replication, DNA helicase attaches itself to the double stranded DNA and breaks the hydrogen bonds between the 2 strands. Next, free nucleotides pair with complementary bases on each strand of ...

Answered by Akthar Hussain M. • Biology tutor

2825 Views

Why does an ionic compound (e.g. NaCl) conduct electricity when molten or dissolved in water, but not when it is a solid.

When an ionic compound is a solid, the ions in the ionic lattice are held together by ionic bonds. Due to this, the ions are not free to move around and so cannot carry a charge. When the ionic compound i...

Answered by Akthar Hussain M. • Chemistry tutor

3719 Views

Is the excitation and de-excitation of an electron from the ground state (of an atom) due to the collision of another particle (e.g. electron) an elastic collision or an inelastic collision.

It is an elastic collision. This is because, when a particle collides with the electron of an atom, a discrete amount of energy is transferred from the particle to the electron. This discrete amount of en...

Answered by Akthar Hussain M. • Physics tutor

2361 Views

Choose an example of a negative externality and explain one policy which may help to solve it.

Smoking, specifically tobacco, is an example of a negative externality in that it harms negatively those outside of the original transaction. For example, a person walking down a high street inhaling seco...

Answered by Sam B. • Economics tutor

2144 Views

What is a social class?

Social class is a way of categorising people according to certain qualities they may have, or conditions in their life. In the United Kingdom this can be things like your parents' jobs, what kind of educa...

Answered by Ciara C. • Sociology tutor

4780 Views