Top answers


Ella has just finished running a half marathon. She hasn't been drinking enough water so is dehydrated and is feeling incredibly hot. Describe how her body responds to these changes. (6)

She is dehydrated so osmoreceptors in the hypothalamus shrink, this causes ADH to be secreted by the pituitary gland. The ADH travels in the blood stream and acts on the collecting ducts of the kidney nephro...
NH
Answered by Natasha H. Biology tutor
3317 Views

Edexcel 2017, Q8) A square, with sides of length x cm, is inside a circle. Each vertex of the square is on the circumference of the circle. The area of the circle is 49cm. Work out x.

First we should draw what the question tells us. Draws circle with square inside it We want to find out some extra information about the circle based on what we have been told. How can we do this?Well we kno...
AB
Answered by Alex B. Maths tutor
8064 Views

Why does tanx = sinx/cosx ?

This identity can easily be shown by asking the student to draw a right-angled triangle, with one of the remaing two angles labelled x, and labelling the respective oppposite, adjacent and hypotenuse sides O...
SR
16315 Views

How do I know when to use avoir and when to use être in the passé composé - the perfect tense?

The passé composé - the perfect tense - is used for talking about completed events in the past, such as 'I bought an apple', and it is formed using an auxiliary verb the present tense and a past participle. ...
IM
Answered by Isobel M. French tutor
3166 Views

Give two differences between a plant and animal cell

Answers are any 2 of the following: 1) plant cells have a cell wall whereas animal cells do not2) plant cells have vacuoles whereas animal cells do not3) plant cells have chloroplasts whereas animal cells do...
SJ
Answered by Sarah J. Biology tutor
3065 Views