Practise IB Biology HL C2.2 with membrane-potential traces and synapse data covering action potentials, neurotransmitters, saltatory conduction, summation and drugs.
Draw a labeled diagram to show the structure of a motor neuron.
Explain how nerve impulses pass from one neuron to another neuron.
Outline how neurons generate a resting potential.
Neurons transmit electrical impulses. Which statement describes part of this process?
ions are pumped out of the cell to depolarize the membrane.
Ion channels let diffuse into the cell to depolarize the membrane.
ions are pumped into the cell to repolarize the membrane.
Ion channels let diffuse into the cell to depolarize the membrane.
Draw a labeled diagram to show the structure of a motor neuron.
Earthworms (Lumbricus terrestris) have a nerve cord on the ventral (underside) side of their body. It contains three nerve fibres (axons), each with a very large diameter, which extend along the whole length of the nerve cord. There is one medial giant fibre (MGF) and two lateral giant fibres (LGFs). The diameter of the MGF is 1.4 times larger than the LGF.
Scientists developed a non-invasive method to record giant nerve fibre activity. The response from the MGF was measured by the electrical activity produced when touching the front segments of the earthworm while the LGF was measured when touching the back segments.
The table shows the mean conduction rates, standard deviation (SD) and number of individual measurements of MGF and LGF action potentials in each earthworm. At the end of the table, the mean and standard error (SE) for 9 of the earthworms are shown.
Calculate the ratio of the mean conduction rate in the MGF to the mean conduction rate in the LGF.
Suggest one possible reason that the conduction rate in the MGF is much faster than in the LGF.
The diagram shows part of two neurons.
State the name of the structure shown.
The diagram shows part of two neurons.
X indicates the movement of a structure in the neuron. Explain what events trigger this movement and what happens next.
Cholinergic synapses use acetylcholine as their neurotransmitter. They are widespread in the body, passing on signals to muscle cells. These synapses are affected by neonicotinoid pesticides.
The diagrams, which are not drawn to scale, show the synapse between two neurons and a detail of the synaptic cleft.
Explain how acetylcholine initiates an action potential in a postsynaptic membrane.
Cholinergic synapses use acetylcholine as their neurotransmitter. They are widespread in the body, passing on signals to muscle cells. These synapses are affected by neonicotinoid pesticides.
The diagrams, which are not drawn to scale, show the synapse between two neurons and a detail of the synaptic cleft.
Outline how depolarization of the membrane of an axon occurs.
Multicellular organisms benefit from cell specialization and division of labour.
Describe what occurs in a neuron when an action potential is propagated along the axon.
Earthworms (Lumbricus terrestris) have a nerve cord on the ventral (underside) side of their body. It contains three nerve fibres (axons), each with a very large diameter, which extend along the whole length of the nerve cord. There is one medial giant fibre (MGF) and two lateral giant fibres (LGFs). The diameter of the MGF is 1.4 times larger than the LGF.
Scientists developed a non-invasive method to record giant nerve fibre activity. The response from the MGF was measured by the electrical activity produced when touching the front segments of the earthworm while the LGF was measured when touching the back segments.
The table shows the mean conduction rates, standard deviation (SD) and number of individual measurements of MGF and LGF action potentials in each earthworm. At the end of the table, the mean and standard error (SE) for 9 of the earthworms are shown.
State the apparatus used to show the resting and action potentials.
Earthworms (Lumbricus terrestris) have a nerve cord on the ventral (underside) side of their body. It contains three nerve fibres (axons), each with a very large diameter, which extend along the whole length of the nerve cord. There is one medial giant fibre (MGF) and two lateral giant fibres (LGFs). The diameter of the MGF is 1.4 times larger than the LGF.
Scientists developed a non-invasive method to record giant nerve fibre activity. The response from the MGF was measured by the electrical activity produced when touching the front segments of the earthworm while the LGF was measured when touching the back segments.
The table shows the mean conduction rates, standard deviation (SD) and number of individual measurements of MGF and LGF action potentials in each earthworm. At the end of the table, the mean and standard error (SE) for 9 of the earthworms are shown.
Explain saltatory conduction.
Cholinergic synapses use acetylcholine as their neurotransmitter. They are widespread in the body, passing on signals to muscle cells. These synapses are affected by neonicotinoid pesticides.
The diagrams, which are not drawn to scale, show the synapse between two neurons and a detail of the synaptic cleft.
On the diagrams, label:
On the diagrams, label with a letter P a location where a neonicotinoid pesticide could bind.
Describe how decision-making in the central nervous system (CNS) can result from the interaction between the activities of excitatory and inhibitory presynaptic neurons at synapses.
The following images identify brain activity associated with a specific function.
State the diagnostic tool used for functional analysis in the images.