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Biology

A Level

What is the Bohr effect and how does it affect oxygen unloading?

The Bohr effect describes the change in affinity for oxygen haemoglobin has as a result of an increased partial pressure of CO2. It occurs due to the reaction between CO2 and H20, catalysed by carbonic an...

Answered by Tom M. • Biology tutor

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What enzymes are used in the process of DNA replication and what are they used for?

The two enzymes used in DNA replication are DNA helicase and DNA polymerase.The DNA helicase is used to break the hydrogen bonds between the two DNA strands so that the strands can unzip. After fre...

Answered by Seraphima G. • Biology tutor

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Glycogen and amylose are used for energy storage. Glycogen is found in animals. Amylose is found in plants. Describe how the structure of glycogen allows it to perform its function and explain the advantage to animals of using glycogen as an energy

First of all I'd realise that the questions is asking you to make a comparison between glycogen and amylose and their suitability, so would advise the candidate to make two separate bullet point lists for...

Answered by Laura G. • Biology tutor

15301 Views

Describe the Benedict's test for reducing sugars and how this can be modified to test for non-reducing sugars

Take 1-2cm³ of the sample in a test tubeAdd a few drops of Benedict's reagent to the test tube Heat the test tube in a water bath Leave for 5 minutes Observe the colour of the precipitate forme...

Answered by Jennifer P. • Biology tutor

8412 Views

Describe how the structure of the renal corpuscle facilitates ultrafiltration.

In the human body, ultrafiltration is the non-specific filtration of blood at a molecular level under high pressure. Renal corpuscles are the starting point of nephrons (the functional units of the kidney...

Answered by David N. • Biology tutor

15637 Views