If you smell something really nasty like a dirty nappy you either just wrinkel your nose or your gag-reflex is activated. This reflex used to be to protect us from eating things which can harm us e.g.: mouldy food or faeces.
reflex arc
Afferent pathway
Reflex Arc
Afferent pathway
Reflexes are rapid involuntary responses to a given stimuli. The reflex pathway that only has one synapse in the CNS is called the monosynaptic reflex arc.
The neural pathway of a single reflex is called a reflex arc. It involves the sensory neuron carrying information from the receptor to the spinal cord, where it synapses with a motor neuron that carries the response signal to the effector muscle or organ. This simple pathway allows for rapid, involuntary responses to stimuli.
The nostrils are connected to the brain through the olfactory nerve, which is responsible for the sense of smell. Each nostril connects to the brain through a different pathway, but both nostrils contribute to the overall sense of smell.
The optic nerve (cranial nerve II) carries sensory information about light intensity to the brain as part of the afferent pathway in the pupillary reflex.
To remember the stages of a reflex arc in chemistry, you can use the acronym "SAID" which stands for stimulus, afferent pathway, integration center, and efferent pathway, and then the response. This mnemonic can help you recall the order of events in a reflex arc.
The short pathway that carries the impulse for an automatic response is called a reflex arc. It involves sensory neurons, interneurons in the spinal cord, and motor neurons to quickly produce a reflex action in response to a stimulus, bypassing the brain.
The simplest pathway of an impulse involves the sensory neuron transmitting a signal to the interneuron in the spinal cord, which then relays the signal to the motor neuron, causing a response in a muscle or gland. This pathway is known as a reflex arc and allows for rapid, automatic responses to stimuli without involving the brain.
The salivary reflex, which is a parasympathetic reflex, leads to the secretion of saliva. This reflex is triggered by the presence of food in the mouth or by the thought, smell, or sight of food.