Control And Coordination Notes

Control and Coordination Class 10 Science chapter explains how organisms manage body activities and thereby respond to environmental changes. It covers how the nervous system and endocrine system regulate body functions in humans. On the other hand, plants use chemical signals for coordination. |

The topic connects biology and physics concepts. Hence, helping students understand how reflexes, impulses, and hormones work together to maintain balance in living beings.

Nervous System and Its Function

In animals, control and coordination are mainly handled by the nervous system, which sends electrical messages called impulses. The human nervous system includes:

• Central Nervous System (CNS): Brain and spinal cord; process and control actions.
• Peripheral Nervous System (PNS): Cranial and spinal nerves linking the CNS to other organs.
• Autonomic Nervous System (ANS): Controls involuntary functions such as heartbeat and breathing.

A neuron is the functional unit that carries impulses through dendrites, axon, and synapse using neurotransmitters. Reflex actions are instant, automatic responses managed by the spinal cord through a reflex arc, such as pulling a hand away from a hot object.

Brain Structure and Function

The brain is the main control center for all body coordination. It is protected by the cranium, meninges, and cerebrospinal fluid. The brain’s main parts are:

• Forebrain: Controls thinking, memory, and voluntary actions.
• Midbrain: Connects brain parts and controls eye movement.
• Hindbrain: Includes the cerebellum, pons, and medulla; manages balance, breathing, and heartbeat.

The brain and spinal cord together maintain coordination by processing inputs and generating correct responses.

Endocrine System and Hormonal Coordination

The endocrine system complements the nervous system through chemical messengers called hormones. They travel in the bloodstream and have long-lasting effects. Major glands include:

• Pituitary Gland: Regulates growth and controls other glands.
• Thyroid Gland: Secretes thyroxine for metabolism.
• Adrenal Glands: Release adrenaline in emergencies.
• Pancreas: Produces insulin to control blood sugar.
• Testes/Ovaries: Secrete reproductive hormones.

Hormonal imbalance can cause diseases such as diabetes, goiter, and dwarfism. Together, the nervous and endocrine systems maintain internal stability.

Coordination in Plants

Plants lack a nervous system but show control and coordination through hormones and movements. Main hormones are:

• Auxins: Help in cell elongation and bending toward light.
• Gibberellins: Stimulate stem and fruit growth.
• Cytokinins: Promote cell division.
• Abscisic Acid: Inhibits growth and helps during stress.

Plants exhibit tropic movements (directional, like phototropism and geotropism) and nastic movements (non-directional, like folding of Mimosa leaves).