Nervous & Hormonal communication

Receptors, effectors & stimuli:

• A stimulus is any detectable change in the internal or external environment
• Receptors detect stimuli- can be either cells or proteins on cell membranes
• Effectors are cells which bring about a response to the stimulus via nervous or hormonal communication, e.g. muscle cells

Nervous vs Hormonal communication:

Nervous:

• Short lived- neurotransmitters removed once they finish their job
• Localised- neurotransmitters are released directly onto cells
• Fast- impulses are fast, allowing quick reactions

Nervous system sends info as electrical impulses using neurones...

Types of Neurone:

• Sensory- transmit impulses from receptors to central nervous system (CNS)
• Relay- transmit impulses between sensory and motor neurones
• Motor- transmit impulses from CNA to effectors

Stimulus--> receptors…