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Name two ways in which meiosis produces genetic variation.

Independent segregation (of homologous chromosomes) Crossing over Random assortment
DL
Answered by Daisy L. • Biology tutor
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Explain how the body responds to a fall in water potential.

Providing there is a basic understanding of the anatomy and functioning of the kidney, we can start by stating that the homeostatic control of osmoregulation in the blood is achieved by hormone ADH (anti-diu...
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Answered by Alexandra S. • Biology tutor
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Describe how phagocytosis of a virus leads to presentation of its antigens

Firstly, specialised white blood cells, known as macrophages, detect the virus in the blood stream. This is due to the virus releasing chemicals, and in the process of chemotaxis, the macrophage follows this...
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Answered by Jennifer L. • Biology tutor
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How is an action potential transmitted across a synapse?

Looking at a cholinergic synapse:The action potential arrives at the presynaptic knob. This causes voltage-gated calcium ion channels to open, and calcium ions to diffuse into the presynaptic knob.The influx...
MM
Answered by Megan M. • Biology tutor
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Rat poison is not always an effective rodenticide and will reduce in effectiveness with age. Explain why

Any type of poison is not guaranteed to eradicate rats entirely. This is due to genetic mutations allowing an individual to be immune to certain types of toxins. Whilst the population may be eradicated, if e...
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Answered by Charles D. • Biology tutor
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