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Describe the three different types of point mutation, and explain for each what the effect on the final gene product is likely to be

Base insertion/addition. This is when a base pair is added to a sequence - for example AGTCGTAGC could become AGTCGATAGC. In this situation, a frame shift occurs, and every c...

Answered by Rachel H. • Biology tutor

2419 Views

Give the name and describe the process by which macrophages kill pathogens.

Phagocytosis. Macrophage picks up signals of pathogen, extends cytoplasm around pathogen and engulfs it in a vesicle. Lysosomes diffuse towards the vesicle through the cytoplasm, fuse and the (lytic) enzy...

Answered by Isabel B. • Biology tutor

1722 Views

What is the difference between the xylem and phloem?

the xylem transports water and minerals the plants need. water is taken up from the roots normally and is needed at the leaves. so the direction of flow in the xylem is only upwards. also is made of dead ...

Answered by Najma A. • Biology tutor

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If populations of species become isolated, new species are more likely to develop. Explain why. (2 marks)

The organisms are unable to exchange genes outside of the isolated population. There may be different selective pressures which the organisms must adapt to. This means the features of the species may chan...

Answered by Hannah M. • Biology tutor

2148 Views

Describe the process of phagocytosis

The phagocyte comes into contact with pathogen and phagocytic receptors detect the pathogen as 'non-self'. The phagocyte then binds to pathogen and engulfs the pathogen by the process of endocytosis. This...

Answered by Tanzima U. • Biology tutor

1716 Views