Respiratory and Circulatory Systems

Vocabulary flashcards detailing the anatomical structures, pathways, components, and primary functions of the human respiratory and circulatory systems.

Respiratory System

A complex network of organs and tissues that plays a crucial role in breathing and gas exchange, facilitating the intake of $O_2$ and the expulsion of $CO_2$, a waste product of metabolism.

Nasal Cavity

The first entry point for air; it filters, warms, and humidifies air before it reaches the lungs, and contains olfactory receptors that detect smells.

Pharynx

A muscular tube connecting the nasal cavity and mouth to the larynx and esophagus that plays a role in both respiration and digestion.

Larynx (Voice Box)

A structure located below the pharynx that houses the vocal cords and is responsible for producing sound as passing air vibrates the cords.

Trachea (Windpipe)

A tube connecting the larynx to the bronchi that transports air to and from the lungs; it is lined with cilia to trap dust and pathogens.

Bronchi

The two main branches (left and right) formed by the division of the trachea that lead into the lungs and subdivide into smaller bronchioles.

Gas Exchange (Respiratory System)

The process by which oxygen is absorbed into the bloodstream and carbon dioxide is released from the blood into the alveoli to be exhaled.

Regulation of Blood pH

A respiratory function that maintains acid-base balance by adjusting the levels of $CO_2$ in the blood.

Protection (Respiratory System)

The mechanism of filtering out harmful particles and pathogens through mucus and cilia located in the airways.

Olfactory Receptors

Receptors situated within the nasal cavity that detect smells.

Circulatory System

Also known as the cardiovascular system, a vital organ system responsible for transporting blood, nutrients, oxygen, carbon dioxide, hormones, and waste products throughout the body to maintain homeostasis.

Heart

The central four-chambered pump of the circulatory system responsible for moving blood through pulmonary and systemic pathways.

Right Atrium

The chamber of the heart that receives deoxygenated blood returning from the body.

Right Ventricle

The chamber of the heart that pumps deoxygenated blood to the lungs.

Left Atrium

The chamber of the heart that receives oxygenated blood from the lungs.

Left Ventricle

The chamber of the heart that pumps oxygenated blood out to the rest of the body.

Arteries

Blood vessels that carry oxygen-rich blood away from the heart, except for the pulmonary arteries, which carry deoxygenated blood to the lungs.

Veins

Blood vessels that carry deoxygenated blood back to the heart, except for the pulmonary veins, which carry oxygenated blood from the lungs.

Capillaries

Tiny blood vessels that facilitate the exchange of oxygen, carbon dioxide, nutrients, and waste products between blood and tissues.

Red Blood Cells (Erythrocytes)

Blood cells that transport oxygen throughout the body using hemoglobin.

White Blood Cells (Leukocytes)

Blood cells that form part of the immune system and function to fight infection.

Platelets

Components of the blood that help facilitate blood clotting.

Plasma

The liquid component of blood that carries cells, nutrients, hormones, and waste products.

Systemic Circulation

The pathway involving the movement of oxygenated blood from the left ventricle to the rest of the body and returning deoxygenated blood to the right atrium.

Pulmonary Circulation

The pathway involving the movement of deoxygenated blood from the right ventricle to the lungs and back to the left atrium as oxygenated blood.

Waste Removal (Circulatory System)

The process of transporting metabolic waste products through the blood to the kidneys for excretion.

Nutrient Distribution (Circulatory System)

The delivery of nutrients from the digestive tract to cells throughout the body via the bloodstream.