Control and Coordination: Nervous system, Parts and its Functions

Control and coordination is carried out by the nervous system in the human body which contains three types of nerves: cranial, spiral and visceral. A human body is connected through these nerves as they run throughout the body and helps in sending and receiving messages. They help in controlling and coordinating our actions based on the environment . 

Control and Coordination in Humans

The nervous system and the endocrine system generate and secrete hormones, which are responsible for human control and coordination. The five sense organs of our body, the eyes, ears, nose, tongue, and skin, are known as receptors, and they work by receiving information from our surroundings. As a result, the sensory organs, neurological system, and hormones all play a role in human and animal reaction and coordination. 

Control and Coordination

For example, when we eat, our bodies engage in a variety of synchronized processes. The nose distinguishes food smells, while the hands act as ingestion organs. Food digestion is aided by the alimentary canal and glands. As a result, numerous organs carry out coordinated tasks.

Nervous System

In animals, the nervous system is a sophisticated regulating mechanism. It not only organizes activities, but also conveys sensory information and messages to and from many bodily regions.

The neuron is the entire system's structural and functional unit.

A movement is defined as an organism's capacity to move a certain bodily component. Locomotion refers to an organism's capacity to move its entire body from one location to another. Movement is a reaction to stimuli for the organisms.

The nervous system of an animal is made up of specialized tissues known as nervous tissues. The neuron is a structural and functional element of the nervous system that is in charge of coordinating and directing complicated animal activities. Neurons are specialized cells in the nervous system that transmit nerve impulses. They are split into three parts:

• Axon: axon is the neuron's storey, which culminates in thin hair-like structures called axon terminals. The nerve impulses are used by these axon terminals.
• Cell body: The site on the cell body of neurons is star-shaped with different hair-like features projecting out of the edge. Dendrites are fine structures that resemble hair and receive nerve signals.
• Myelin Sheath: the myelin sheath is an insulator that surrounds the axon. It protects the axon from the nerve impulse and the environment.

Types of Neurons

• Sensory neurons receive information from sensory organs and process them.
• Motor neurons are nerve cells that transmit impulses to a gland or muscle.
• The impulses between a motor neuron and a sensory neuron are relayed by these neurons, also known as relay or association neurons.

Parts of the Nervous System

Vertebrates have a unique nervous system that is split into two sections:

1. Peripheral Nervous System: The PNS is made up of everything except the brain and spinal cord. Nerves and everything that runs down the spinal cord are included. It is in charge of transporting data from all areas of the body to the brain. Peripheral nerves are nerves in the PNS that link our sensory organs, as well as all other organs, blood vessels, and other body parts, to the CNS.
2. Central Nervous System: The brain and spinal cord make up this structure. This is where sensory feelings are generated. Memories are formed as a result of the production of thoughts and emotions. It collects data from all throughout the body and synchronizes its activities as a result. Apart from sensory movements, it also regulates our breathing rate, heart rate, body temperature, and so forth.

Organs of the Human Nervous System

Human Nervous system has three main organs. These are given below:

1. Brain
2. Spinal Cord
3. Nerves

Brain: 

The human brain is a complex organ made up primarily of nerve tissue. To fit a vast surface area into a small space, the tissues are severely folded. Meninges are a three-layered membrane structure that surrounds the brain. Between the meninges is filled with cerebrospinal fluid. The brain is protected from mechanical shocks by the CSF suppliers. In addition, there is security. The forebrain, midbrain, and hindbrain are the three areas of the human brain.

• The forebrain is the portion of the brain that controls and coordinates all voluntary processes. It is also the part of the brain that thinks.
• The hindbrain and forebrain send impulses to the midbrain.
• It aids in the regulation of vision, hearing, and temperature, among other things.

Spinal Cord: 

The spinal cord is a thick nerve that runs through the backbone hollow. Its top portion is linked to the brain. It is connected to all areas of the body via nerves and governs all of the body's activities by transferring information from the sensory organs to the brain.

Nerves: 

The brain and spinal cord are connected to every area of the body through nerves. In our bodies, there are three kinds of nerves:

• All regions of the head are connected to the brain through cranial nerves.
• All regions of the body are connected to the spinal cord through spinal nerves.
• The spinal cord and the internal organs are connected via visceral nerves.

Functions of the Nervous System

Conduction and transmission of nerve impulses are the primary functions of the nervous system. The information is sent through a nerve impulse. It describes any electrical, chemical, or mechanical disruptions in a neuron caused by a stimulus. With the aid of neurotransmitters, a nerve impulse is sent across the synapse. A neuron does not carry electricity. On the surface, it has a positive membrane and on the inside, it has a negative membrane. A neuron's resting potential ranges from 70 to 90. As a result, the membrane is said to be polarized. The sodium-potassium pump keeps the resting potential constant. The extracellular fluid submerges the axon, which is packed with axoplasm. The axon's sodium-potassium pump transports three sodium ions from the axoplasm to the extracellular fluid and two potassium ions from the extracellular fluid to the axoplasm. The enzyme Sodium-potassium ATPase is responsible for the conduction.

When a stimulus is delivered, sodium ions begin to flow inside and potassium ions begin to rush outward. The permeability of the axon membrane changes, and the pump stops working. The membrane is considered to be depolarized when its resting potential is -70mV and its action potential is +30mV. The action potential is known as a nerve impulse because it travels down the membrane.

The sodium-potassium pump reactivates after a period of action potential, and the axon membrane is repolarized by the resting potential.

Reflex Action and Reflex Arcs

All activities that are not within our control are referred to as reflex actions. That is to say, these behaviors are entirely voluntary. For instance, sneezing, coughing, blinking, and so on. It is a reflexive reaction to stimuli.

The reflex arc is the path that nerve impulses travel during a reflex action. There are two types of reflexes: spinal reflexes, which only involve the spinal cord, and cerebral reflexes, which only involve the brain.

The relay neuron in the spinal cord receives signals from the sensory neurons, which transfer them from the sensory organ. The motor neuron transmits these impulses back to the muscles. The sensory organ is moved away from danger by the muscles connected to it.

Hormones in Animals

Plants are simpler than animals. For control and coordination, they have a number of specialized organs that execute specific activities. The nervous system (nervous system) and chemical coordination are responsible for animal coordination (Endocrine System). Both of these systems function in animals in a coordinated manner to control numerous bodily activities. Different endocrine glands and hormones make up the endocrine system. Animals' endocrine glands assist in chemical coordination. Hormones are substances that they secrete. They are unique messengers that regulate a variety of bodily activities, such as appetite, body temperature, mood, growth and development, metabolism, and reproductive processes, among others. Endocrine glands are sometimes known as ductless glands since they lack a conduit.

Functions of Hormones in Animals

• Ensures appropriate development.
• Responsible for ensuring adequate maturation and growth in a timely manner.
• Ensures that reproduction occurs at the appropriate moment.
• Thyroid hormones such as Thyroxine (T4) and Thyronine (T3), for example, impact daily metabolism.

Control and Coordination in Plants

Plants coordinate, but not in the same manner that mammals do. Some plants are small, while others are tall, and some are thick while others are sparse. The presence of hormones known as plant hormones has an impact on all of these factors. Plant growth regulators or phytohormones are other names for these hormones. Plants use phytohormones to govern and coordinate their activities. This movement is always done in a well-organized and regulated manner. But, if plants can coordinate as well, why can't we perceive any movement or change? This is because plants' responses to such reactions are virtually too sluggish, to the point where we may not see a change in plants for weeks or months. When we stop watering a plant, it does not die or wither away in a day or two; instead, it takes a week or more to wither away.

Things to Remember

• Control and coordination is a part of Science syllabus, unit 2, World of living 
• It carries a total of 5 to marks and 12 to 14 periods. 
• In a human body the nervous system and endocrine system helps in control and coordination activity.
• Control and coordination is different in plants and animals.
• The conduction and the transmission of the nerve impulse is the main function of the nervous system.