Term 3 Grade 9 Biology Vocabulary Flashcards

Comprehensive vocabulary flashcards covering the Circulatory, Respiratory, and Excretory systems based on the Grade 9 Term 3 Biology study guide.

Artery

Blood vessels that carry oxygen-rich blood away from the heart.

Vein

Blood vessels that carry oxygen-poor blood to the heart and contain valves.

Capillary

Microscopic blood vessels where the exchange of $O_2/CO_2$, nutrients, and waste occurs.

Heart

A 4-chamber pump that circulates blood throughout the body.

Plasma

The liquid component of blood that carries nutrients and waste.

Red Blood Cells (RBCs)

Blood components that transport oxygen using hemoglobin.

White Blood Cells (WBCs)

Blood components responsible for fighting infection.

Platelets

Blood components that cause blood to clot at the site of wounds.

Valve

A structure in veins and the heart that prevents the backflow of blood.

Pacemaker

A specialized group of cells that regulates the pace of the heart's rhythm.

Atherosclerosis

A condition involving the narrowing or hardening of the arteries.

Hemoglobin

An iron-containing protein in red blood cells that binds to and transports oxygen.

Trachea

The windpipe that serves as the main airway leading toward the lungs.

Bronchus

The large air passages that branch off from the trachea into the lungs.

Alveolus

Microscopic sacs in the lungs that serve as the site of gas exchange via diffusion.

Breathing

The physical process of inhalation and exhalation that facilitates gas exchange.

Internal Respiration

The gas exchange that occurs between the blood and body cells.

External Respiration

The process of gas exchange in the lungs involving $O_2 \rightleftharpoons CO_2$.

Diaphragm

The muscle that contracts to expand the chest during inhalation and relaxes during exhalation.

Kidney

An excretory organ responsible for filtering blood.

Lungs (Excretory)

Organs that excrete carbon dioxide and water vapor as waste.

Skin

An excretory organ that removes waste from the body through sweat.

Homeostasis

The maintenance of a stable internal environment within the body.

Nephron

The functional unit of the kidney responsible for filtration.

pH balance

The regulation of acidity or alkalinity levels within the body's internal environment.

Filtration

The process of removing waste products from the blood in the excretory system.