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Biology
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The surface run-off of nitrate from agricultural fertiliser into freshwater ponds and lakes can cause the death of the fish. Explain how this happens.

This question crops up a lot and may be up to a five mark question, if you learn the key points and terms you can be confident of getting all the marks you can here! 

First of all,

SM
Answered by Sarah M. Biology tutor
5140 Views

What is an enzyme?

An enzyme is a protein that act as a biologcal catalyst, meaning that they will activate a biological reaction. 

Enzymes are very specific and will work with a specific substrate. You can...

LJ
Answered by Laureen J. Biology tutor
5648 Views

Why is the genetic code described as being universal?

The genetic code refers to DNA, which is like a blueprint that can be found in all living organisms. DNA is made up of 4 nucletotides: Adenine (A), Thymine (T), Guanine (G) Cytosine (C), whether in a b...

LJ
Answered by Laureen J. Biology tutor
33536 Views

State and explain two adaptations of a red blood cell?

Red blood cells have a biconcave disk shape, meaning that it increases their surface area and allows for more rapid diffusion of oxygen into and out of the cell.

Red blood ...

JD
Answered by Joe D. Biology tutor
23892 Views

How do internal stimuli affect a positive and a negative feedback loop?

Deviation from homeostasis causes the activation of feedback loops in order to restore equilibrium to the organism. 

An example of a negative feedback loop is the homeostasis of blood glu...

AK
Answered by Alexia K. Biology tutor
6783 Views

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