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Explain the concept of 'threshold potential' in the initiation of an action potential

Action potentials are only initiated when depolarization above a certain level occurs, this level is known as the 'threshold potential'. 'Vm' is the resting membrane potential (voltage) and the depolarizi...

Answered by Tutor101969 D. • Biology tutor

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Explain the role of B-lymphocytes and T-lymphocytes in the defence of the body against a virus infection (6 Marks)

A virus is a pathogen which contains antigens on its cell surface. These antigens are detected and digested by macrophages. The two pathways involved in the detected and elimination of the virus is the ce...

Answered by Sumaiya R. • Biology tutor

6927 Views

(A) express 4^x in terms of y given that 2^x = y. (B) solve 8(4^x ) – 9(2^x ) + 1 = 0

(A) express 4^x in terms of y given that 2^x = y. we know that 2² = 4....

Answered by Sadat T. • Maths tutor

35824 Views

In terms of structure and bonding explain why the boiling point of magnesium is much higher than that of bromine?

Bromine is molecular, existing as Br2 molecules, wheras magnesium is metallic and therefore exists in a large macromolecular structure. In bromine there are strong INTERmolecular covalent bonds, but only ...

Answered by Edwina B. • Chemistry tutor

27789 Views

"Why is Mathematics important, I wont use any of it when I start work?"

This is a common question asked by young students and adults, which demotivates them to study and prevents passion from being the driving force during the tougher chapters. Mathematics is used in every in...

Answered by Ashish T. • Maths tutor

3635 Views