Top answers

Biology
A Level

What is the difference between the humoral and cell-mediated immune repsonses?

The humoral repsonse removes the pathogenic microorganisms which don't enter the cells and requires antibodies produced by B lymphocyctes. Different B lymphocyte cells produce different antibodies, eac...

LC
Answered by Lily C. Biology tutor
39818 Views

When do mutations not cause a change in amino acid sequence?

The genetic code is degenerate- this means that amino acids can be coded for in more than one way. In an mRNA sequence coding for a protein, each amino acid in the protein is encoded b...

EP
Answered by Ellen P. Biology tutor
6282 Views

What is DNA replication and how does the cell cycle regulate cell division?

DNA replication is the production of two identical DNA strands from one original DNA molecule and is a nearly error-free process that occurs in all living organisms. This is because, in order for a cel...

AA
Answered by Azeem A. Biology tutor
11314 Views

What is the difference between interspecific competition and intraspecific competition?

Define competition: competition is an interaction between organisms where one organism has a negative effect on the fitness of the other organism

Define interspecific competitio...

ZG
Answered by Zoe G. Biology tutor
29483 Views

How does an invading pathogen cause disease?

There are three main ways that an invading pathogen can result in disease:

 

Damage or destroy host cells

This is host specific and ligands on the pathogen mus...

JC
Answered by Jenny C. Biology tutor
4917 Views

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