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Why is the probability of inheriting Cystic Fibrosis 25% if both parents are only carriers? How did you get that figure?

(This would be after I have introduced the punnett square - I will draw this out for the student) Remember that each parent contributes one allele for a given gene to their offspring. For cystic fibrosis we ...
JL
Answered by Jasmine L. • Biology tutor
8847 Views

Mutations can occur in DNA. Describe what effect a mutation can have on the function of an enzyme.

A mutation is a change in the DNA base sequence. This causes a change in the amino acid that is synthesised, and this could change the shape of the active site on an enzyme. The shape of the active site may ...
MS
Answered by Mahdia S. • Biology tutor
36807 Views

Describe a typical cycle of a PCR reaction.

Polymerase Chain Reaction or PCR is the process of amplifying a sample of DNA. The first stage of a PCR cycle is known as the denaturation phase. This occurs at a temperature of 95C and lasts for approximate...
MB
Answered by Max B. • Biology tutor
6579 Views

What is the equation for photosynthesis and what is the product used for?

Equation: carbon dioxide + water ---(with light energy)---> glucose + oxygen Glucose is the important product of the photosynthesis reaction. Some of the glucose is used in respiration to provide energy f...
IR
Answered by Isabelle R. • Biology tutor
23869 Views

Why do cells have receptors that allow viruses to invade?

Rather than cells having receptors specific to viruses, cells have receptors specific to molecules it needs to acquire from outside the cell, such as glucose (needed for respiration). It is the viruses who a...
ER
Answered by Emily R. • Biology tutor
5001 Views