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Describe and explain how the alveoli are adapted to perform efficient gaseous exchange

The alveoli are arranged in clusters at the end of the bronchioles in the lungs. The lungs contain an extremely large surface area of alveoli (around 70m2) which acts to provide the maximum space for the ...

Answered by Joe P. • Biology tutor

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What mass of sodium hydroxide would need to be dissolved to make 100 cm^3 of a 0.5 mol dm^-3 solution? (3 marks)

Number of moles = (0.5 x 100)/1000 = 0.05 moles (1 mark)Molar mass, M, of NaOH = 23 + 16 + 1 = 40 (1 mark)Mass of NaOH needed = moles x M = 0.05 x 40 = 2g (1 mark)correct answer alone scores 3 markscorrec...

Answered by Aarif A. • Chemistry tutor

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I've heard the word supertonic before. What does this mean?

Each of the seven scale degrees in the major and minor scales has been given a fancy name:TonicSupertonicMediantSubdominantDominantSubmediantLeading toneThese names are often used when re...

Answered by Liam G. • Music tutor

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Assess the positive and negative impacts of rapid development on either a named developing or emerging country.

India
Rapid development has led to both positive and negative social, economic and environmental impacts in India. Rapid development has led to improved health care which has positive social impacts ...

Answered by Rhys J. • Geography tutor

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Describe the sodium-potassium ion pump on cell plasma membranes (2 marks)

These pumps use ATP / active transport to move 3 sodium ions (Na⁺) out of the cell for every two potassium ions (K⁺) that move in.1 mark - idea of active transport / use of ATP1 mark...

Answered by Aarif A. • Biology tutor

3532 Views