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Describe the primary, secondary, tertiary and quaternary structure of proteins.

PrimaryThe amine group of one amino acid reacts with the carboxyl group of another during a condensation reaction to form a peptide bond. The products of this reaction are a dipept...

Answered by Hannah D. • Biology tutor

6649 Views

When would you use perfect tense and when would you use the pluperfect?

The perfect tense is used when in English you would say something has/ hasn't happened: for example, 'she has read the book', 'he hasn't finished it ye...

Answered by Anna M. • Spanish tutor

1656 Views

What is the difference between DNA, mRNA and tRNA? and why are they different?

DNA, tRNA and mRNA are all essential macromolecular biological molecules involved in genetics and protein production. The two major categories of genetic molecules are DNA and RNA, with both tRNA and mRNA...

Answered by Tristan V. • Biology tutor

52748 Views

What are the main differences between the verbs 'ser' and 'estar'? Demonstrate your understanding with the use of examples.

While both 'ser' and 'estar' mean 'to be' in English, there are some crucial differences between both verbs which are essential to get right at any level of Spanish. There are certain 'rules of thumb' tha...

Answered by Hector P. • Spanish tutor

1635 Views

Evaluate the integral ∫2x√(x^2 +1) dx

The first step is deciding on the method of integration. For this integral it makes the most sense to use substitution.Let u = x² + 1Differentiate w.r.t x => du/dx = 2xRearrange for dx=> ...

Answered by Sam C. • Maths tutor

8594 Views