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What is the difference between Evolution and Natural Selection?

The theory of Evolution by Natural Selection was first proposed by Darwin in 1859. Evolution is the observation that species change over time, for example the beak of birds getting larger or the neck of g...

Answered by Anna D. • Biology tutor

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Why is CO2 a linear molecule whereas H2O has a v-shaped geometry?

This is due to the different numbers of electrons in each molecule and VSEPR (Valence Shell Electron Repulsion) theory. This theory states that as electrons are negatively charged, the valence electrons i...

Answered by Caroline W. • Chemistry tutor

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Trolley A carrying mass 10kg is moving at speed 5m/s, and collides with stationary Trolley B carrying a mass 5kg. Indicating which Law you would apply, what is the speed and direction of Trolley B if Trolley A's resulting movement is 2m/s to the left?

By the Law of Conservation of Momentum, Initial Momentum=Final Momentum, in a closed system.

Take movement to the right as + and to the left as -

Therefore equate the...

Answered by Parinita S. • Physics tutor

3014 Views

Enzyme inhibitors are often used as antiretroviral drugs in the treatment of HIV. Describe the structure of an enzyme and suggest how antiretroviral drugs would work in the treatment of HIV.

Enzymes are globular (globe-like) proteins, meaning they exist as 3D structures. As a protein, it is composed of a chain of amino acids which is able to fold into secondary structures such as alpha-helice...

Answered by Declan C. • Biology tutor

2772 Views

What are genes and how do work?

Genes are the code that makes up all life on Earth. Genes are sections of the long chain-like molecule called DNA, which is found coiled up into chromosomes in the nucleus of cells. The most important par...

Answered by Anna D. • Biology tutor

2593 Views