Human Body Systems Review

Circulatory System

Also known as the Cardiovascular system, it transports nutrients and oxygen to the body.

Heart

A muscular organ that pumps blood throughout the body, usually beating 60 to 100 times per minute.

Arteries

Blood vessels that carry oxygenated blood away from the heart.

Veins

Blood vessels that bring deoxygenated blood back to the heart.

Capillaries

The smallest blood vessels, connecting arteries to veins, allowing gas exchange.

Pulmonary Arteries

The only arteries that carry oxygen-poor (deoxygenated) blood from the heart to the lungs.

Trachea

Also known as the windpipe, it splits into bronchi that lead to each lung.

Diaphragm

A dome-shaped muscle that aids in breathing by contracting and expanding.

Alveoli

Tiny sacs in the lungs that allow for gas exchange between the air and blood.

Skeletal Muscle

The only voluntary muscles that require conscious thought to move.

Smooth Muscle

Involuntary muscles that control organs without conscious thought.

Cardiac Muscle

Involuntary muscle found in the heart that pumps blood.

Kidneys

Organs that filter waste from blood, maintain water level, and produce urine.

Urine

Waste filtered from blood by the kidneys, primarily composed of water.

Spinal Cord

The major highway for nerve signals traveling between the brain and the body.

Neurons

Nerve cells that transmit signals between the brain and the rest of the body.

Bones

Living tissues that provide structure, support, and protect organs.

Peristalsis

The pattern of muscle contractions that move food through the digestive tract.

Esophagus

A muscular tube that transports food from the mouth to the stomach.

Villi

Small finger-like projections in the small intestine that absorb nutrients.

Liver

An organ that processes nutrients and produces bile to aid in fat digestion.

Gallbladder

A small organ that stores bile produced by the liver.

Pancreas

An organ that produces digestive enzymes and hormones, including insulin.

Skin

The largest organ of the body, providing protection against pathogens.

Antibodies

Proteins produced by the immune system to identify and neutralize pathogens.

Lymphatic System

A network that collects leaked fluid from blood and is part of the immune system.

Hormones

Chemical messengers secreted by glands to regulate body functions.

Homeostasis

The process by which the body maintains a stable internal environment.