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Colour blindness is a recessive trait caused by an error in the X chromosome. A couple without color blindness are expecting their second child. Their first child was born colour blind. What is the probability of their second child being colour blind?

Colour blindness is recessive, which implies that the child needs to have both chromosomes carrying the genetic error to be born with this condition. We know this is linked to the sex chromosome X so we w...

Answered by Sabela R. • Biology tutor

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Name two ways in which meiosis produces genetic variation.

Independent segregation (of homologous chromosomes) Crossing over Random assortment

Answered by Daisy L. • Biology tutor

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Explain how the body responds to a fall in water potential.

Providing there is a basic understanding of the anatomy and functioning of the kidney, we can start by stating that the homeostatic control of osmoregulation in the blood is achieved by h...

Answered by Alexandra S. • Biology tutor

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Given f(x): 2x^4 + ax^3 - 6x^2 + 10x - 84, and knowing 3 is a root of f(x), which is the value of a?

For this exercise we need to be aware of the factor theorem.The factor theorem states when f(c) = 0 then x - c is a factor of the polynomial f(x) and c is a root of f(x). Because we are told that one of t...

Answered by Sabela R. • Maths tutor

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A sigma0 particle with mass 1193 MeV/c^2 decays into a lambda0 particle with mass 1116 MeV/c^2 a photon. Find the energy and momentum of the photon, assuming that the kinetic energy of the lambda0 particle is negligible.

This is a standard A-level particle physics question. To solve it, we need to use three equations given in the formula sheet of the paper. To find the energy of the photon, we use Einsteins famous energy-...

Answered by Peter F. • Physics tutor

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