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What is the difference between mRNA and pre-mRNA in a eukaryotic cell?

The major difference between pre-mRNA and mRNA is that pre-mRNA is the immediate product of transcription which is comprised of both exons (coding sequences) and introns (non-coding sequences). After tran...

Answered by Matt Y. • Biology tutor

42100 Views

Consider the infinite series S=Σ(from n=0 to infinite) u(down n) where u(down n)=lim (from n π to (n+1) π) ((sin t)/t) dt. Explain why the series is alternating.

For the first part of the question we need to try and understand what is actually happening – we have the sum of an integral – where we are summing a sequence of definite integrals. So when n = 0 we have ...

Answered by Stuart D. • Maths tutor

6052 Views

Find an equation of the curve with parametric equations x=3sin(A) and y=4cos(A), in the form bx^2+cy^2=d.

x²=9sin²(A) and y²=16cos²(A)Since sin²(A)+cos²(A)=116x²+9y²=16 x 916x²+9y²=144

Answered by Pranav V. • Maths tutor

3726 Views

Describe the changes in the lungs during inspiration

During inspiration, the intercostal muscles contract, moving the sternum up and out. This increases the thoracic volume, hence decreasing the pressure. The pressure gradient set up causes air inflow from ...

Answered by Dhaval N. • Biology tutor

2885 Views

Outline and Explain the Logical and Evidential Problems of Evil for the Existence of God. (30)

The original Problem of Evil is often attributed to the ancient Greek philosopher EPICURUS (341-270BC).
If God can do nothing about the evils in the world, then He is not omnipotent.If He does not s...

Answered by Maya K. • Philosophy and Ethics tutor

10855 Views