Human Body Systems: Nervous, Circulatory, and Cardiac Function

The Nervous System

The nervous system is responsible for processing information and coordinating responses throughout the body.

Nerve Centers

These centers process the information that reaches the sensory organs and elaborate answers.

The Brain

The brain is located in the head, protected by the skull bones. It has an oval shape. It consists of three main parts: the cerebrum, the cerebellum, and the brainstem.

The Spinal Cord

The spinal cord is a long cord that runs inside the backbone. It is connected directly to the brain.

The Cerebellum

The cerebellum is one of the parts of the encephalon, along with the cerebrum and brainstem. One of its most representative functions is to coordinate voluntary movements of the human body. The cerebellum integrates all information received to precisely command and control what the cerebral cortex sends to the locomotor system through motor pathways.

Nerves

Nerves are fine and long fibers that run throughout our body. They connect the nerve centers with the sensory organs and other body parts.

Neuron Types

• Sensitive Neurons: Take information from the receptors to the central nervous system, i.e., towards the encephalon and spinal cord.
• Motor Neurons: Send information from the effector to the central nervous system and cause muscle contraction or gland secretion.
• Association Neurons (Interneurons): Located in the central part of the nervous system. They connect sensory neurons with motor neurons.

Nervous Tissue Components

White Matter

Mainly consists of axons covered by myelin.

Gray Matter

Composed of the cell bodies of neurons and dendrites.

Electrocardiography

Electrocardiography Defined

Electrocardiography is the interpretation of a cardiogram.

Electrocardiogram Defined

An electrocardiogram is a transthoracic recording of the electrical activity of the heart over time, captured externally by skin electrodes.

The Circulatory System

The circulatory system is vital for transporting substances throughout the body.

The Heart

The heart is a muscular organ about the size of a fist, responsible for propelling blood through blood vessels. It is located in the middle of the chest, between the two lungs.

Blood Vessels

Blood vessels distribute nutrients and oxygen throughout the body, while also collecting waste products of cellular metabolism and leading them to the organs responsible for eliminating them.

Lymphatic System

The lymphatic system is a crucial part of the immune and circulatory systems.

Lymphatic Vessels

Lymphatic vessels are vessels that have a structure similar to that of veins. They are the result of the confluence of lymphatic capillaries. They drain into the circulatory system, with internal valves.

Lymph Nodes

Lymph nodes are enlargements that occur along lymphatic vessels. They filter and remove foreign substances and microorganisms from the lymph to prevent them from entering the bloodstream.

Capillary Nodes

Capillary nodes are responsible for collecting interstitial fluid.