Differentiate between the following: Cerebrum and cerebellum Sensory and motor neuron Voluntary and involuntary action Nerve impulse and hormonal transmission Short-sightedness and long-sightedness Rods and cones Endocrine glands and exocrine glands Negative and positive feedback mechanisms
1. Cerebrum and Cerebellum:
Cerebrum: The largest part of the brain, involved in higher brain functions like thought, memory, reasoning, and voluntary movements. It is divided into two hemispheres and controls sensory perception and complex cognitive tasks.
Cerebellum: Located below the cerebrum, it controls balance, posture, and fine motor skills. It coordinates voluntary movements and ensures smooth, precise motions.
2. Sensory and Motor Neuron:
Sensory Neuron: Transmits sensory information from sensory receptors (e.g., skin, eyes) to the central nervous system (CNS).
Motor Neuron: Carries signals from the CNS to muscles or glands, initiating movement or secretion.
3. Voluntary and Involuntary Action:
Voluntary Action: Conscious, controlled actions that are initiated by the brain, such as moving your hand or walking.
Involuntary Action: Unconscious actions controlled by the autonomic nervous system, like heartbeats, digestion, and breathing.
4. Nerve Impulse and Hormonal Transmission:
Nerve Impulse: Electrical signals transmitted along neurons, typically fast, and used for short-distance communication within the nervous system.
Hormonal Transmission: Chemical signals released by endocrine glands into the bloodstream, traveling long distances to target organs, with slower but longer-lasting effects.
5. Short-Sightedness and Long-Sightedness:
Short-Sightedness (Myopia): The inability to focus on distant objects because the image forms in front of the retina. Can be corrected with concave lenses.
Long-Sightedness (Hyperopia): The inability to focus on close objects because the image forms behind the retina. Can be corrected with convex lenses.
6. Rods and Cones:
Rods: Photoreceptor cells in the retina responsible for vision in low-light conditions and peripheral vision. They do not detect color.
Cones: Photoreceptor cells in the retina responsible for color vision and detail in bright light conditions.
7. Endocrine Glands and Exocrine Glands:
Endocrine Glands: Secrete hormones directly into the bloodstream (e.g., thyroid, adrenal glands). Their products have widespread, long-lasting effects.
Exocrine Glands: Secrete their products (such as enzymes, sweat) through ducts to the outside of the body or into body cavities (e.g., salivary glands, sweat glands).
8. Negative and Positive Feedback Mechanisms:
Negative Feedback: A process that works to counteract changes, maintaining homeostasis. If a system deviates from its set point, negative feedback works to return it to normal (e.g., regulation of body temperature).
Positive Feedback: A process where the output of a system amplifies the change, often pushing it to completion. An example is childbirth, where contractions increase in intensity until delivery.