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When a vaccine is given to a person, it leads to the production of antibodies against a disease-causing organism. Describe how. (5 marks)

With these 5 and 6 mark questions, one of the main skills required is being able to describe the process in sufficient detail, without wasting time with unnecessary information. For example in this questi...

Answered by Thomas R. • Biology tutor

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Name the components/organelles of both animal & plant cells. Give a brief description of their functions.

Animal CellsCell membrane - Made up of lipids and proteins and allows for passive diffusion into the cell. Cytoplasm - Contains cytosol & cell organelles. Nucleus - Controls the activities of t...

Answered by Sameerah V. • Biology tutor

2947 Views

How do we control the concentration of urine?

Osmoregulation is the homeostasis of water in the body. It is important that water volumes are kept relatively constant as this influences electrolyte concentrations and cell activity.

Answered by Adam B. • Biology tutor

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What does the term "Semi-conservative" mean in relation to DNA?

DNA is a double stranded helix. During DNA replication, the strands are separated from each other (using an enzyme called DNA helicase). The unzipped DNA strands then utilize another enzyme, known as DNA ...

Answered by Catherine A. • Biology tutor

3874 Views

Membranes of pre-synaptic and post-synaptic neurons play an important role in transmission of nerve impulses. Explain the principles of synaptic transmission. (8marks)

Synapse is the gap between two adjacent neurons in which neurotransmitters are released. Arriving action potential depolarises pre-synaptic membrane. This causes voltage gated calcium channels in membrane...

Answered by Alla K. • Biology tutor

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