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A plant is moving mineral ions from the soil into its roots by the process of active transport. Does this suggest that the concentration of ions is higher in the soil or the roots?

The concentration is higher in the soil. The process of active transport is used to move molecules against the concentration gradient (from a low to a high concentration). Therefore the concentration of i...

Answered by Alice M. • Biology tutor

10546 Views

Explain the Polymerase Chain Reaction (PCR) as a technique to make copies of DNA.

PCR takes place in three stages - denaturation, annealing, and extension. The process begins with a very small quantity of DNA being loaded into a PCR machine. The hydrogen bonds that exist between the tw...

Answered by Aashna B. • Biology tutor

4001 Views

Prove algebraically that n^3+3n^2+2n+1 is odd for all integers n

To show this we should consider when n is odd and when n is even,If n is odd then we can find an m such that n=2m+1. Substituting n=2m+1 and expanding gives 8m^3+12m^2+6m+1+12m^2+12m+3+4m+2+1=8m^3+24m^2+2...

Answered by Alistair P. • Maths tutor

5338 Views

If a star with a radius of 600000km has a surface temperature of 6000K, calculate its luminosity

Use the formula Luminosity = (Surface temperature)^4Surface area Stefan's constantCalculate surface area with 4piradius^2Area=4.5210^18therefore luminosity= 4.5210^18 * (6000)^4...

Answered by • Physics tutor

2157 Views

What happens at the junction between neurons?

Neurons are the basic cells in the nervous system. They are made up of a soma, axon, dendrites and synapse. The synapse is the end part of the neuron that is in charge of sending a message from one neuron...

Answered by Sean D. • Biology tutor

3853 Views