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Give one piece of evidence that supports the theory that mitochondria evolved from prokaryotic cells.

Mitochondria contain 70S ribosomes (as opposed to 80S which would be found in other eukaryotic organelles) the same as prokaryotic cells. They also have their own DNA (mtDNA) which is separate from the DN...

Answered by Lucy E A. • Biology tutor

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Describe why organisms may become extinct due to a change in the climate

Species like polar bears might go extinct if, for example, sea level rise drastically decreases the size of their territory meaning they have less area to roam, hunt and mate in so they cannot reproduce f...

Answered by Lucy E A. • Biology tutor

3081 Views

Explain how enzymes work in reactions (3 marks)

Enzymes catalyse reactions by reducing the activation energy required to begin a chemical reaction, without being used up in the reaction. They bind to the active site of a substrate to form an enzyme-sub...

Answered by Lucy P. • Biology tutor

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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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