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Highlight 3 differences between mRNA and DNA molecules

mRNA is only single stranded, whereas DNA is a double stranded molecule 2. mRNA has Uracil instead of thymine which is found in DNA 3. mRNA contains no introns as they have been spliced out, however...

Answered by Safia A. • Biology tutor

3335 Views

What is a synapse and how is information transmitted across it?

Synapse = the junction between two neurones (nerve cells) OR the junction between a neuron and an effector cell such as a muscle cell

A synapse between two neurones consists of:

Answered by Emma Louisa S. • Biology tutor

2404 Views

What are the differences between the structure and function of arteries and veins?

Arteries are blood vessels that carry blood away from the heart. They have thicker walls than veins in order to cope with far higher blood pressure level...

Answered by William H. • Biology tutor

8410 Views

Why do humans have a double circulatory system?

Ask the student: what other option is there? What are the differences between the two?

Answer: Humans have a small surface area to volume ratio, so diffusion alone is not enough to meet the high m...

Answered by Divya V. • Biology tutor

7160 Views

How do I explain the process of Natural Selection?

VOSSAG V - Variation: all organisms undergo varying amounts of genetic variation due to genetic mutations or environmental factors (such as geographic separation). O - Overpopulation: all...

Answered by Ben K. • Biology tutor

5102 Views