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How does a chemical synapse transmit an action potential?

The action potential reaches the pre-synaptic knob causing depolarisation. This causes voltage-gated calcium channels in the pre-synaptic membrane to open. Calcium ions enter the pre-synaptic knob through...

Answered by Kathryn B. • Biology tutor

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Name and describe the function of the different organelles within a cell, and compare the differences within a plant and an animal cell.

Nucleus- controls cell's activity. DNA transcription occurs here. Stores DNA (genetic material).Cytoplasm- some cell reactions occur here. Fluid-Jelly-like environment. Glycolysis occurs here.Mitochondria...

Answered by Anaelle T. • Biology tutor

2744 Views

What is the series of events that occur when an action potential enters the presynaptic neuron

The membrane around the presynaptic neurone depolarises This depolarisation causes Ca2+ voltage-gated channels to open and Ca2+ influxesCa2+ causes vesicles with specific neurotransmitters to migrate to t...

Answered by James A. • Biology tutor

2576 Views

How is gas exchange in a human facilitated?

The gas exchange of O2 and CO2 must occur between the air-filled alveoli of the lungs and our blood circulation running through our vessels. Near our lung alveoli lie capillaries coat the alveoli. The cap...

Answered by Hosna S. • Biology tutor

4115 Views

The binding of one molecule of oxygen to haemoglobin makes it easier for a second oxygen molecule to bind, explain why.

The binding of the first oxygen changes the tertiary structure of the haemoglobin. This uncovers the second binding site, allowing the second oxygen to bind.

Answered by Abbie T. • Biology tutor

12157 Views