• The nervous system perceives stimuli from the environment.
• There are various receptors, both external and internal.
• Signals travel via sensory neurons to the central nervous system (CNS).

✨ Fun Fact: Think of your nervous system like the ultimate Wi-Fi network. It receives data from all over, processes it, and tells the body how to respond. It's like getting a Snapchat notification and then deciding whether to open it or not!

Sensory Receptors: Detect changes in the environment.

• Located in the skin and sense organs.
• Examples
  • Nerve endings that sense touch and heat.
  • Light-sensitive rod and cone cells in our eyes that help us see!

Imagine this: It's like your skin and eyes acting as antennas, picking up signals (stimuli) from around you.

Monitor conditions inside the body.

• Stretch Receptors in Muscles: Detect muscle contractions. This lets your brain figure out if you're slouching or standing tall.
• Stretch Receptors in Arteries: They're like the body's barometers, measuring blood pressure.
• Chemoreceptors in Blood Vessels: Act like tiny scientists, analyzing if we have high or low levels of oxygen, carbon dioxide, and glucose.

Real World Example: It's like the sensors in a car. They let you know if the engine's too hot or if you need to refuel.

• Signals from receptors are sent to the CNS by sensory neurons in the form of nerve impulses.

• These travel through axons. Fun fact: an axon might be over a meter long if the receptor is at your toe's end!

• Brain gets signals from main organs in the head (e.g., eyes & ears).

• Spinal cord receives signals from other parts of the body (e.g., skin & muscles).

• Specific parts of the brain handle different signals. E.g., the visual cortex processes what we see.

  Think of it like this: It's as if your body is a big city, and the neurons are the highways, ensuring that messages (cars) get to the right destination.