What happens if the threshold poteu,l82;4iw7v+i ywtpx4+s lzmyf py 8a ntial is not reached ?

  At what membrane potential do voltage-gag . :6t61kjhpijhd*g fak;qu 4ted sodium channels open?

  The diagram shows a nsa,+qn eb8xdnozt dh dl.10).b, hl(keuron.
Which arrow indicates a dendrite?

  How do neonicotinoid 7bias:arqs)9 pesticides work?

  The diagram shows an action potential. wu v;hnj,m3ou 0,uh n1

What is happening at point X?

  Which is the correct definition of saltato bp 2icjc5 bu10rg 2opj09+txhry conduction?

Neuronal cells have special membrane properties.cs(6.fuh dpsm 9om4luo.ng pzf792n that allow their axons to propagate action potential from one cell to another. The diagram below shows a portio oh4cfp.sf.s dp9m l2u nu(.g796on mzn of an axonal plasma membrane.


1.(1)State the role of a sodium-potassium pump in axon.
(2)Describe the action of the sodium-potassium pump.
2.Distinguish between simple diffusion, facilitated diffusion and active transport.
3.Compare and contrast sodium-potassium pumps and potassium channels.

  What causes the exocytosis,qi/b g :ker,j of neurotransmitters at the presynaptic membrane?
I. Depolarisation of the postsynaptic membrane
II. Depolarisation of the presynaptic membrane
III. The diffusion of calcium ions

  What are the main factors that maintain a neuron’s resting potentid fy31 rq1y2bmal?

  What is not a function of the myelin sheath?

Explain how the restin*(7 u t-zzjotxa+i 7eng potential is maintained in a neuron.

The diagram represents a synaptic cleft between two neurons 3:w/ ,lpwaxnpin an insect's nervous syw pna/x, lw:p3stem.



Gardeners use pesticides that contain neonicotinoids to kill pests. Label with the letter X where neonicotinoids would bind.
1.(1)Explain how neonicotinoids work on insects.
(2)Suggest what the effect would be on synaptic transmission in cholinergic synapses if gardeners used (3)pesticides that were broken down by acetylcholinesterase.
2.Explain why neonicotinoid containing pesticides are less toxic to mammals than insects

1.Draw and label the structure of a typical:) x(t 00idtpk6itij*rrnu)ly/kpg) neuron.
2.Explain why myelination is essential for the rapid transmission of impulses.
3,Explain the importance of positive ions in the generation and propagation of an action potential.

Neonicotinoids are synthetic e.5zfa)yufw9 ,h0rq t compounds that are widely used as pesticides. However, there are concerns about their effecah0.9fu5tryqz f, we) t on honey bees and other pollinating insects. The table below shows the results from a study where honey bees (Apis mellifera carnica) were treated with non-lethal doses of two neonicotinoids, Imidacloprid and Clothianidin, and the effect it had on their homing instinct (ability to fly back to their hive).

1.Describe the mode of action of pesticides containing neonicotinoids on cholinergic synapses in insects.
2.Using the data, outline the effect of the neonicotinoids on honey bees.
3.Calculate the percentage increase between the control and those treated with 0.6 μM of Imidacloprid which did not arrive back at their hive.
4.State what the dependent variable is in this study.
5.(1)Based on the data, predict the effect that exposing honey bees to neonicotinoids will have on the fitness of the honey bee colony.
(2)Explain your answer to part (i).
6.The researchers concluded that neonicotinoids should not be used as pesticides due to their unintended effects on honey bees. Evaluate whether this data supports their conclusion.

  The graph below shows membrane voltage ov6rdox r;bu 85 :*gp3fr o+iojwer time during an action potential. Which letter represents the segment of the action potential when voltage-gated sodium wf+6o;jrirg3 pdoxuro8b5 :*channels are open and voltage-gated potassium channels are closed?

  Which two features are more abundant per unit length in a a1 0p5*)4 pxry2cjz0rpzuf ow))s1ty iwp cr(non-myelinated neuron tha0(yp)5p oysu 1t*zj rxiz2r0r)c wa1wp) f4 cpn in a myelinated neuron?

  Which of the following is a/are corda65t :zxu:mm/xgh 4z7velw/rect description(s) of the relative speed impulses are/ agzxluehz7vd/mt:5:m xw 6 4 conducted at?
I. As the diameter of axons increases, the speed at which impulses are conducted increases.
II. There is a negative correlation between animal size and the speed at which impulses are conducted.
III. Saltatory conduction in myelinated neurons is slower than the speed at which impulses are conducted in non-myelinated neurons.

  The diagram shows a process that occurs in the me;p dx+,p(j rrtee ex(4mbranes of neurons during a stage of the action potential. What process does eeje(rp4dxr+;p( ,xt the diagram depict?

  The image shows neurons that are found i4,qfyb okyz0*x.7lzt)5ibu wn dog brains. What does letter X indicate?5.ol)7z iqf xz0wbu4bt *yy ,k

  The diagram shows two neurons of equal length and diameter. Wh3/zcm1q+ mp k jljiz h:e(lx21ich neuron will transfe+(1i1k/mm qz 3jzhpx2c jl:ler an electrical impulse faster?

  Which triggers the relf / *qtqiad v )/8kiq3lk;-pbrease of neurotransmitters from the presynaptic membrane?

  Which mode of transp4s*m upj)+06 o4hz mt*rawsfbort do neurotransmitters use to travel across a synapse?

  Which statement explains why a nerve impulse isu5mdq67c ;cln electrical?

1.Explain why a resting potential 04io 9sv/ly nlkig( .kis negative.
2.Explain how the structure of a neuron is adapted to its function.
3.Describe the events that occur to propagate an action potential within a neuron and between two neurons.