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Explain 3 ways in which a leaf is adapted for photosynthesis. [6 marks]

Can efficiently absorb sunlight- upper part of leaf contains tightly packed palisade mesophyll cells; cells have large vacuole which pushes chloroplasts to the edge of leaf and well devel...

Answered by • Biology tutor

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y=x^2 +4x-12, Find the Range (co-domain) when the domain of x is (1) -6 to 2 inclusive (2) the set of real numbers, R.

This question usually comes up at AS level where students have prior knowledge of quadratic functions:We need to 1) understand the 'shape' 2) locate the roots 3) Find the turning point 4) sketch the graph...

Answered by Pascal T. • Maths tutor

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Why does gravitational potential energy have a negative value?

A point in a gravitational field has an associated gravitational potential. It is defined as the work done required to bring a unit mass from a point an infinite distance to that point in the field. At an...

Answered by Joseph P. • Physics tutor

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The distinction between the imperfect tense and the passé composé

The imperfect tense and the passé composé are both past tenses which are used in different situations. The imperfect tense is used in three main cases:Habitual actions-> What

Answered by Assunta S. • French tutor

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Describe how B-lymphocytes respond when they are stimulated by antigens.

When B-lymphocytes are stimulated by antigens, they first divide by mitosis to form clones, some of which become plasma cells that secrete antibodies, others become memory B-cells which can be stimulated ...

Answered by • Biology tutor

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