Human Body Systems Practice Flashcards

Vocabulary-style flashcards covering the organs and functions of the digestive, cardiovascular, respiratory, and skeletal systems.

Mouth

The organ where the digestive process begins, using teeth to chew food and saliva with enzymes to break down carbohydrates.

Peristalsis

Wave-like contractions that move food down the esophagus to the stomach.

Chyme

A semi-liquid mixture of food, stomach acid, and enzymes formed in the stomach.

Bile

A substance produced by the liver and stored in the gallbladder that helps break down fats.

Pancreas

An organ that produces enzymes for digestion and releases hormones like insulin to regulate blood sugar.

Small Intestine

The main site of nutrient absorption where enzymes and bile help break down food for the bloodstream.

Large Intestine

Absorbs water and electrolytes from undigested food and contains bacteria that produce certain vitamins.

Rectum

A storage area for waste that signals the body when it is time for elimination.

Anus

The final opening of the digestive tract where waste exits the body.

Heart

A muscular organ with four chambers that pumps oxygen-rich blood to the body and oxygen-low blood to the lungs.

Arteries

Blood vessels with thick, elastic walls that carry blood away from the heart to the rest of the body.

Veins

Blood vessels with valves and thinner walls that carry blood back to the heart.

Capillaries

Tiny blood vessels connecting arteries and veins that allow oxygen, nutrients, and waste to move between blood and tissues.

Hemoglobin

A protein in red blood cells that carries oxygen and gives blood its red color.

White Blood Cells

Cells of the immune system that help the body fight off infections and harmful invaders.

Platelets

Blood components that form a plug to help blood clot and prevent excessive bleeding.

Pulmonary Circuit

The pathway that carries blood from the heart to the lungs for oxygen and back to the heart.

Systemic Circuit

The pathway that delivers oxygen-rich blood from the heart to the body and returns oxygen-poor blood back.

Pharynx (Throat)

A passageway connecting the nose and mouth to the larynx for air movement.

Larynx (Voice Box)

A structure containing vocal cords that produces sound and acts as a gateway to keep food out of the airway.

Trachea (Windpipe)

A tube made of cartilage rings that carries air from the larynx to the bronchi.

Alveoli

Tiny air sacs where oxygen passes into the blood and carbon dioxide moves out.

Diaphragm

A dome-shaped muscle under the lungs that contracts to help with inhalation and relaxes for exhalation.

Pleura

A thin membrane surrounding the lungs and lining the chest cavity to reduce friction during movement.

Skull

A structure made of $22$ bones fused together that protects the brain and forms the head shape.

Mandible (Jaw)

The only movable bone in the skull, used for chewing food and speaking.

Vertebral Column (Spine)

A support structure made of $33$ vertebrae that protects the spinal cord and allows bending.

Rib Cage

A protective structure for the heart and lungs made of $12$ pairs of ribs, the sternum, and thoracic vertebrae.

Sternum (Breastbone)

A flat bone in the center of the chest that connects to the ribs.

Clavicles (Collarbones)

Bones that connect the breastbone to the shoulder blades and support shoulder movement.

Radius & Ulna

Two bones in the forearm; the radius is on the thumb side and the ulna is on the pinky side.

Femur

The longest and strongest bone in the body, which supports weight and enables movement like walking and running.