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What is the difference between facilitated diffusion and active transport?

When moving across a selectively permeable membrane, ions, polar and large molecules cannot dissolve easily in the lipid membrabe. Instead, transport must occor by way of protiens that act as carriers or cha...
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Answered by Shannon G. • Biology tutor
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Describe how human gonads are under hormonal control.

Gamete production is controlled by hormones in humans. The hypothalamus produces Gonadotrophin-releasing hormone (GnRH) which in turn stimulates the anterior pituitary gland to produce leutinizing hormone (L...
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Answered by Martin F. • Biology tutor
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Explain how DNA is converted into protein in eukaryotes.

DNA is a nucleic store of genetic information in eukaryotes. It consists of a combination of four different nucleobases; adenine, cytosine, guanine and thymine (abbreviated to A, C, G and T respectively). So...
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Answered by Martin F. • Biology tutor
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Microbiological techniques- gel electrophoresis

Scientists in labs use a technique called gel electrophoresis which allows them to separate a mix of DNA fragments by size . This is used in conjunction with PCR (polymerase chain reaction) and restriction d...
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Answered by Lizzie B. • Biology tutor
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Why do energy and biomass decrease at successive stages of the foodchain?

Energy is transferred throughout the food chain as animals at lower trophic levels are consumed by those at higher trophic levels. In every living organism, energy is taken in as food. But when one organism ...
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Answered by Katie H. • Biology tutor
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