Types of Synapse

Q.

Name three types of neurons.

Q.

Which of the following statements about the transmission of nerve impulses is incorrect?

1. Nerve impulse travels from dendritic end towards axonal end.

2. At the dendritic end electrical impulses bring about the release of some chemicals which generate an electrical impulse at the axonal end of another neuron.

3. The chemicals released from the axonal end of one neuron cross the synapse and generate a similar electrical impulse in a dendrite of another neuron.

4. A neuron transmits electrical impulses not only to another neuron but also to muscle and gland cells

Q.

Receptor sites for neurotransmitters are present on

1. Membranes of synaptic vesicles

2. Presynaptic membrane

3. Tips of axons

4. Postsynaptic membrane

Q.

Which of the following is the protein present in bone?

1. Myosin

2. Elastin

3. Collagen

4. Ossein

Q. Why are neurons called excitable cells? Mention special features of the membrane of the neuron?

Q. Neurotransmitters are stored in

1. Synaptic vesicles
2. Post-synaptic neuron
3. All of the above
4. Synaptic knob

Q. A fluid filled area between presynaptic knob and postsynaptic membrane is known as

1. synaptic vesicle
2. synapse
3. synaptic cleft
4. synaptic knob

Q.

In a neuron, conversion of electrical signal to a chemical signal occurs in

1. cell body

2. axonal end

3. dendritic end

4. axon

Q. Which of the following statements is incorrect?

1. Synaptic cleft of neurons secrete adrenaline
2. Myelinated nerves fibres are enveloped with Schwann cells that form myelin sheath around axon
3. Spinal cord and cranial nerves are made of myelinated nerve fibres
4. Non-myelinated nerve fibres are enclosed by Schwann cells that do not form myelin sheath

Q. Which of the following is incorrect about electrical synapses?

1. The synaptic cleft is only 0.2 nm.
2. Electrical synapses are abundant in our system.
3. Impulse transmission through an electrical synapse is faster than chemical synapses.
4. All of the above are correct

Q.

Differentiate between sensory and motor neuron.

Q.

Are membranes of pre and postsynaptic neurons at chemical synapsis associated?

Q. In the diagram given, parts labelled as a, b, c, d, e and f are respectively identified as

1. Egg, synergids, central cell, filiform apparatus, antipodals and polar nuclei
2. Central cell, polar nuclei, filiform apparatus, antipodals, synergids and eggs
3. Synergids, polar nuclei, central cell, antipodals, filiform apparatus and egg
4. Filiform apparatus, polar nuclei, egg, antipodals, synergids and central cell
5. Polar nuclei, egg, antipodals, central cell, filiform apparatus and synergids

Q. Which of the following is a correct match?

1. Alkaloids - Carotenoids
2. Terpenoids - Morphine
3. Lectins - Abrin
4. Drugs - Curcumin

Q.

State the location and functions of the parts given below :
Axon.

Q. What is the bulbous structure present at the terminal end of each branch of the axon called ?

1. synaptic knob
2. synaptic vesicle
3. synaptic cleft
4. synapse

Q.

Messages that take the form of electrical signals are known as

1. sensory neurons

2. nerve impulses

3. motor neurons

4. reflex arc

Q.

Which of the following statements concerning cardiac muscle is correct?

1. The force of contraction is increased by circulating adrenaline

2. Heart muscle contracts in response to action potentials in the autonomic nerve fibres

3. The action potential has the same duration as that of skeletal muscle

4. All of the Ca2+required for contraction enters a myocyte during the plateau phase of the action potential

Q. Which of the following options is not correct about the structure marked as ‘a’ in the given figure below.

1. It is formed by Schwann cells.
2. It slows the conduction of electrical impulses.
3. It is made up of protein and fatty substances
4. It is an insulating layer

Q.

What is the effect of alcohol and caffeine on the nervous system?

Q. A nerve impulse is transmitted from one neuron to another through junctions called synapses. Which one is not part of synapse?

1. Post synaptic membrane
2. Presynaptic membrane
3. Synaptic cleft
4. Nissl's granules

Q.

What is meant by synapse

Q. The chemical causing the transmission of nerve impulse across synapse is

1. Acetylcholine
2. Choline
3. Cholinesterase
4. Acetic acid

Q.

Write the function of sensory neurons and motor neurons.

Q. Choose the incorrect statement w.r.t an electrical synapse.

1. Pre and post-synaptic membrane are in close proximity
2. Transmission of an impulse along a single axon is completely different to transmission of an impulse across an electrical synapse
3. Electrical current can directly flow from one neuron to another across synapse
4. Transmission of an impulse across a chemical synapse is completely different to transmission of impulse across an electrical synapse

Q.

The speed of nerve impulse is 100 m /sec.

1. True
2. False

Q.

Nissls granules are present in which cells?

Q. In which part of neuron Nissls granules are present

1. Cell body
2. Dendrites
3. Axon
4. Both A and B

Q.

Name the area of contact between two neurons.

Q. A list of events occurring in the transmission of nerve impulse across the synapse is given below in a random order.
(i) Opening of specific ion channels allows the entry of ions, a new action potential is generated in the post-synaptic neuron.
(ii) Neurotransmitter binds to the receptor on post synaptic membrane.
(iii) Synaptic vesicle fuses with pre-synaptic membrane, neurotransmitter release into synaptic cleft.
(iv) Depolarisation of pre-synaptic membrane.
(v) Arrival of action potential at axon terminal.
Which of the following options represents these events in a correct order?

1. $\left(v\right)\to \left(iv\right)\to \left(iii\right)\to \left(ii\right)\to \left(i\right)$
2. $\left(i\right)\to \left(ii\right)\to \left(iii\right)\to \left(iv\right)\to \left(v\right)$
3. $\left(i\right)\to \left(ii\right)\to \left(iv\right)\to \left(iii\right)\to \left(v\right)$
4. $\left(v\right)\to \left(iv\right)\to \left(iii\right)\to \left(i\right)\to \left(ii\right)$