12.2.1 Differentiate Between Two Main Types of Coordination in Living Organisms
| Feature | Nervous (Electrical) Coordination | Hormonal (Chemical) Coordination |
| Definition | Rapid communication using electrical impulses via neurons. | Slower communication using chemical messengers (hormones) via bloodstream. |
| Speed | Fast (milliseconds). | Slow (seconds to hours). |
| Duration of Effect | Short-lived, precise responses. | Long-lasting, sustained responses. |
| Transmission | Via neurons and synapses. | Via blood circulation. |
| Examples | Reflex actions (e.g., knee-jerk reflex). | Blood sugar regulation by insulin. |
12.2.2 Identify Main Organs Responsible for Coordination and Control
- Nervous System: Brain, spinal cord, nerves.
- Endocrine System: Pituitary gland, thyroid, adrenal glands, pancreas, gonads (testes, ovaries).
12.2.3 State That Receptors Receive Stimuli and Transmit Information to Effectors Through Central Nervous System
- Receptors: Specialized cells (e.g., photoreceptors in eyes, mechanoreceptors in ears) detect environmental stimuli (light, sound, touch).
- Transmission: Receptors send signals via sensory neurons to the central nervous system (CNS: brain and spinal cord).
- Effectors: Muscles or glands respond to CNS signals to produce an action (e.g., muscle contraction or hormone secretion).