Problem 149 - Objective Biology for NEET

Question

Assertion: The chemical stored in the synaptic vesicles are termed as neurotransmitters. Reason: Synaptic vesicles release these chemicals in the synaptic cleft.

Step-by-Step Solution

Answer

The assertion and reason are both correct and the reason validly explains the assertion. The chemicals stored in synaptic vesicles are indeed neurotransmitters and these are released into the synaptic cleft.

Step 1 - Understanding assertion

The assertion claims that the chemicals stored in the synaptic vesicles are termed as neurotransmitters. This is indeed true, as synaptic vesicles within neurons are known to store chemicals called neurotransmitters.

Step 2 - Understanding the reason

The reason states that synaptic vesicles release these chemicals into the synaptic cleft. This is also a fact, as the primary function of synaptic vesicles is to store neurotransmitters and release them into the synaptic cleft when the neuron 'fires'.

Step 3 - Correlating assertion and reason

Both the assertion and reason are correct facts about the functioning of neurons. Furthermore, they are related since the assertion identifies the chemical stored in the synaptic vesicles (the neurotransmitter), while the reason explains how these very neurotransmitters are released into the synaptic cleft. Hence, the reason successfully explains the assertion.

Key Concepts

Synaptic Vesicles

Imagine tiny bubbles inside a neuron, packed with important chemical signals. These bubbles are known as synaptic vesicles. They are crucial because they store neurotransmitters, the chemicals that allow neurons to communicate with each other. When a neuron is ready to send a message, these vesicles move to the neuron's edge and merge with the cell's membrane. This process is called exocytosis. It allows the neurotransmitters to spill out of the vesicle and into the synaptic cleft.
In essence, synaptic vesicles act like tiny packages that deliver important messages throughout the brain and nervous system.

Synaptic Cleft

The synaptic cleft might sound like a vast canyon, but it's actually a microscopic gap between neurons. This small but crucial space is where neurotransmitters travel between communicating neurons. Imagine two neurons looking like they're almost touching, but there is just enough space to let molecules pass through.
When neurotransmitters are released from the synaptic vesicles, they enter this tiny gap. The synaptic cleft is vital for the signal to continue its journey to the next neuron. Despite its small size, the cleft ensures that messages are precisely delivered and received, enabling the neurons to function as a network.

Neurons

Neurons are the building blocks of the nervous system, functioning like tiny computers that process and transmit information. These unique cells consist of three main parts: the cell body, dendrites, and an axon. The cell body processes input from various sources, dendrites act as antennas receiving signals, and the axon transmits information to other neurons or cells.
A single neuron may connect with thousands of others, forming complex networks in the brain. They are responsible for everything from moving a muscle to remembering a friend's name. When neurons communicate, they use neurotransmitters to pass their messages across the synaptic cleft, tightly coordinating all activities in the body and mind.