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A chromosome is a long, tightly coiled molecule of DNA. Chromosomes are split into sections called genes. In the human body there are 48 chromosomes within each cell (except sex cells which have 23). Chro...
Xylem and phloem are a little bit like the blood vessels we have in our body and make up what is called 'vascular bundles' in plants. Xylem are essential for providing water to the plant by transpiration ...
The populations of finches became separated geographically (on different islands). Then genetic variation developed in these isolated communities. Natural selection acted differently in these isolated com...
receptors detect a changes in the enviroment and effectors allow a response to be made. an example of this would be the jerk reflex when accidentally touching something thats hot. temperature receptors in...
An enzyme is a catalyst which speeds up a reaction by providing an alternative pathway with lower activation energy required.
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