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Two snails belong to the same species. Yellow shelled snails found in grassland areas, dark shelled ones in woodland. Shell colour determined by genes. Explain how natural selection could have caused this distribution of snails

The yellow banded shell provides camouflage to the snail in grassland areas. These are more difficult for the birds to see, so less are eaten by predation. As a consequence, more yellow banded snails survive...
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Answered by Leah B. • Biology tutor
5206 Views

What are the differences between diffusion, osmosis and active transport?

Diffusion is the net movement of particles in solution across a partially permeable membrane. The net movement of particles is from higher to lower concentration gradient. Osmosis is the net movement of wate...
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Answered by Thomas W. • Biology tutor
14801 Views

Describe the conducting circuit in the heart

The heart is a muscular pump which pushes blood out to the body. It does this by contracting the muscle fibres which sqeezes the blood out. The heart has 4 chambers. Blood comes into the top two chambers, ca...
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Answered by Clodagh M. • Biology tutor
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Solve the equation 3x^(2)-7x+3 giving your answer to three significant figures.

Since there is no further factorisation possible we use the quadratic formula x=[-b±√(b 2 -4ac)]/2a. From the equation in question we have a=3, b=-7, c=3. Substituting into the quadratic formula x=[7±√((-7) ...
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Answered by Benjamin H. • Maths tutor
5338 Views

Discuss the disadvantages of using a census to gather population data

Many countries all over the world use censuses to gather information about their population. Questions asked in a census include age, gender, nationality, employment and living situation. A census is usually...
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Answered by Aaron M. • Geography tutor
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