Circulatory System Word Search

A heart and blood vocabulary sheet with its key: the four chambers, the vessels and the parts of blood.

Name Date

Find every word hidden in the grid. Words go across and down.

0 of 16 words found

LCJMSMOSDSSLESO

KANPTHEYCEVUTDS

NPALLATSIPTASAM

AIDAARSTRTAIIEL

FLQTETAECUQSVWS

NLEEZELMUMOEEDG

RAILNROILHXRNHY

BRIEMYOCARDIUMP

IYLTIPMITRALLQU

EFGERDLYIUAFESL

BYTDABLOODOPSBS

HMAVALVENTRICLE

FDIASTOLEGTWVGH

RELPNHPTAWAYOQW

OCORONARYAAEFWK

This grid is wider and taller than its box. Slide it to see every letter.To drag, hold the first letter for a moment, then slide.Keyboard: Tab to the grid, arrow keys to move, Enter on the first and last letter.

VentricleVENTRICLE
SeptumSEPTUM
ValveVALVE
MitralMITRAL
MyocardiumMYOCARDIUM
CoronaryCORONARY
ArteryARTERY
CapillaryCAPILLARY
AortaAORTA
VenuleVENULE
BloodBLOOD
PlateletPLATELET
PulsePULSE
CirculationCIRCULATION
SystemicSYSTEMIC
DiastoleDIASTOLE

16 of 24 words from the Circulatory System Key Terms list.

Start from a list

Easy: words go across and down.

More options

Show clues, not words

Word list

Large print Lower-case letters Name and date line on paper

The puzzle changes as you go. See the puzzle

Answer key: Circulatory System Word Search

LCJMSMOSDSSLESO

KANPTHEYCEVUTDS

NPALLATSIPTASAM

AIDAARSTRTAIIEL

FLQTETAECUQSVWS

NLEEZELMUMOEEDG

RAILNROILHXRNHY

BRIEMYOCARDIUMP

IYLTIPMITRALLQU

EFGERDLYIUAFESL

BYTDABLOODOPSBS

HMAVALVENTRICLE

FDIASTOLEGTWVGH

RELPNHPTAWAYOQW

OCORONARYAAEFWK

VENTRICLE, SEPTUM, VALVE, MITRAL, MYOCARDIUM, CORONARY, ARTERY, CAPILLARY, AORTA, VENULE, BLOOD, PLATELET, PULSE, CIRCULATION, SYSTEMIC, DIASTOLE

Next step Type in the labels from your own heart diagram Scramble the same heart and blood words

All 98 words

Parts of the Heart 22

Apex The lower tip of the cone-shaped heart.
Atrium One of the two upper chambers, which receive blood coming in from the body or the lungs.
Chordae With "tendineae", the cords of tissue known as the heart strings.
Conduction With "system", the pathway that carries the pacemaker's signal to the muscle.
Coronary Describes the arteries that carry oxygenated blood to the heart muscle itself.
Endocardium The innermost layer of tissue, which lines the chambers.
Epicardium The outermost of the wall's three layers.
Fist A human heart is about as big as a closed one.
Heart The muscular organ that pushes blood around the blood vessels.
Leaflet Another word for a cusp, one of the flaps of a valve.
Mediastinum The chest's middle compartment, where the heart is located.
Mitral The valve with two cusps that lies between the upper and lower chambers on the left side.
Myocardium The thick middle layer of the wall, made of involuntary muscle.
Pacemaker The group of cells that produces the electrical impulses setting the rhythm.
Papillary With "muscles", they sit in the lower chambers and attach to the valve cusps by cords.

Show all 98 words (83 more)

Parts of the Heart, continued

Pericardium The fluid-filled sac that contains the heart and the roots of the great vessels.
Semilunar The name shared by the aortic and pulmonary valves, at the exits of the lower chambers.
Septum The stout wall that separates the two lower chambers from one another.
Sinoatrial With "node", the region in the wall of the upper right chamber where the pacemaker cells sit.
Tricuspid The valve that lets blood flow from the upper right chamber to the lower right chamber.
Valve A one-way flap that lets blood flow in only one direction through the chambers.
Ventricle One of the two large lower chambers, which collect blood and expel it to the body or lungs.

Blood Vessels 23

Aorta The main and largest artery in the human body, which leaves the lower left chamber.
Aortic arch The bend between the ascending and descending parts of the largest artery.
Arteriole A small vessel that branches out from an artery and leads to capillaries.
Artery A blood vessel that takes blood away from the heart.
Brachial Describes the major blood vessel of the upper arm.
Capillary The smallest kind of blood vessel, where substances pass between blood and tissue.
Carotid Either of the arteries that supply the head and neck with oxygenated blood.
Endothelium The single layer of cells that lines the inside surface of blood vessels.
Femoral Describes the large artery in the thigh.
Iliac With "common", either of the two arteries that the largest artery splits into in the abdomen.
Jugular Describes the veins that take blood from the head back to the heart.
Lumen The inside space of a tube such as an artery, through which blood flows.
Portal With "vein", the vessel that carries blood from the digestive tract to the liver.
Radial Describes the forearm artery where a pulse may be felt at the wrist.
Renal Describes the paired arteries that supply the kidneys with blood.
Saphenous With "great", the longest vein in the body, running along the length of the leg.
Subclavian Describes the paired arteries below the collarbone that supply the arms.
Tunica From the Latin for coat: a layer of the wall of an artery or vein.
Vascular Describes the system of the heart and blood vessels, from the Latin for vessels.
Vasodilation The widening of blood vessels.
Vein A blood vessel that carries blood towards the heart.
Vena cava Either of two large veins that return deoxygenated blood from the body into the heart.
Venule A very small vein that lets blood return from the capillary beds.

Parts of Blood 28

Albumin A family of proteins commonly found in plasma.
Antibody A large protein the immune system uses to identify and neutralize antigens.
Antigen A molecule that can bind to a specific antibody.
Basophil The least common type of granulocyte, a kind of white blood cell.
Blood The body fluid that delivers nutrients and oxygen to cells and carries their waste away.
Coagulation The process by which blood changes from a liquid to a gel; also called clotting.
Donation When a person voluntarily has blood drawn for use in transfusions.
Eosinophil A white blood cell that helps combat multicellular parasites.
Erythrocyte The scientific name for a red blood cell, the most common type of blood cell.
Fibrin A fibrous protein that, together with platelets, forms a plug over a wound site.
Globulin A family of proteins; with albumins and fibrinogen, the major proteins of blood.
Granulocyte One of the three main subtypes of white blood cell, with lymphocytes and monocytes.
Group With "blood", a classification by the antigens on the surface of red blood cells.
Hematocrit The percentage of blood volume taken up by red blood cells.
Heme A ring-shaped molecule containing iron, a component of hemoglobin.
Hemoglobin The protein containing iron that carries oxygen in red blood cells.
Iron The metal that hemoglobin contains.
Leukocyte The scientific name for a white blood cell, a cell of the immune system.
Lymphocyte A type of white blood cell; T cells and B cells are two kinds.
Monocyte The biggest kind of white blood cell in the blood.
Neutrophil A white blood cell that makes up 40% to 70% of all white blood cells in humans.
Phagocyte A cell that protects the body by ingesting foreign particles and bacteria.
Plasma The light amber liquid part of blood, mostly water, about 55% of its volume.
Platelet A cell fragment with no nucleus that clumps with others to form a clot.
Serum Plasma without the clotting factors.
Stem cell The kind of cell in bone marrow from which all blood cells are derived.
Thrombocyte Another name for a platelet, from the Greek words for clot and cell.
Transfusion The transfer of blood products into a person's circulation.

How Blood Circulates 25

Backflow What the heart valves prevent, so that blood flows one way.
Blood pressure The push of circulating blood against the walls of the vessels.
Cardiac cycle Everything the heart does from the start of one heartbeat to the start of the next.
Cardiac output The volume of blood a single ventricle pumps per unit of time.
Cardiology The study of the heart.
Cardiovascular Describes the system made up of the heart and the blood vessels.
Circuit A complete loop that blood travels; the body has two.
Circulation The movement of blood around the body through the heart and blood vessels.
Closed Describes a system in which blood stays inside the network of vessels.
Diastole The relaxed phase of the cardiac cycle, when the chambers refill with blood.
Exchange What happens at the capillaries, as water and chemicals pass between blood and tissues.
Heartbeat What the heart rate counts: contractions of the heart per minute.
Lymph The fluid that returns from the tissues through its own vessels to be recirculated.
Oxygenated Describes the bright red blood that returns from the lungs.
Pulmonary Describes the circuit that takes blood from the right heart to the lungs and back.
Pulse The rhythmic expansion and contraction of an artery with each heartbeat.
Pump What the heart does to move blood through the vessels.
Resistance What must be overcome for blood to flow through the vessels.
Rhythm The regular pattern of beats, set by a cluster of pacemaker cells.
Spleen An organ, built like a large lymph node, that acts primarily as a blood filter.
Stethoscope A device for listening to sounds inside the body, such as the two sounds of a heartbeat.
Stroke volume The volume of blood pumped from the ventricle per beat.
Systemic Describes the circuit that delivers oxygenated blood to the rest of the body.
Systole The part of the cardiac cycle when chambers of the heart contract.
Venous return The rate of blood flow back to the heart.

How this list was compiled: Own work: the word list and every clue were written for this page. The facts in the clues were checked on 2026-10-08 against English Wikipedia (CC BY-SA 4.0), among them the articles on the circulatory system (https://en.wikipedia.org/wiki/Circulatory_system), the heart (https://en.wikipedia.org/wiki/Heart), the heart valve (https://en.wikipedia.org/wiki/Heart_valve), the blood vessel (https://en.wikipedia.org/wiki/Blood_vessel), blood (https://en.wikipedia.org/wiki/Blood), blood plasma (https://en.wikipedia.org/wiki/Blood_plasma), the white blood cell (https://en.wikipedia.org/wiki/White_blood_cell) and the cardiac cycle (https://en.wikipedia.org/wiki/Cardiac_cycle). A vocabulary list for class, not medical advice. Licence: own work

How it works

This circulatory system word search follows blood from the heart and back. The first grid draws 16 of 24 key terms such as Artery, Vein, Capillary, Atrium, Ventricle, Valve, Plasma and Pulse.

Read the full guide

The heart and the vessels

Under Start from a list, Parts of the Heart has 22 words: the chambers Atrium and Ventricle, the Septum between the lower two, the Mitral and Tricuspid valves, and the three layers of the wall, Epicardium, Myocardium and Endocardium. Blood Vessels has 23, from Aorta and Vena cava down to Arteriole, Venule and Capillary.

The blood and its two circuits

Parts of Blood has 28 words, among them Plasma, Platelet, Hemoglobin and five kinds of white blood cell. How Blood Circulates has 25 and sets Systole beside Diastole and the Pulmonary circuit beside the Systemic one.

Vena cava, Aortic arch and 6 more two-word entries hide as one run of letters: VENACAVA.
Red blood cell is listed as Erythrocyte and white as Leukocyte, so that Blood is never read twice.

Questions and answers

What are the four chambers of the heart?

The upper left and right atria and the lower left and right ventricles. The atria receive blood, the ventricles pump it out, and the heart valves keep it flowing one way.

What are the types of blood vessels?

Five. Arteries carry blood away from the heart and branch into arterioles, which lead to capillaries, where water and chemicals pass between blood and tissues. Venules collect the blood from there, and veins carry it back towards the heart.

What is blood made of?

Blood cells suspended in plasma. Plasma, some 55% of the blood, is mostly water. The cells are mainly red blood cells, the most abundant, white blood cells and platelets.

How does blood flow through the heart?

Blood from the body enters the right atrium, passes to the right ventricle and is pumped to the lungs. It returns with oxygen to the left atrium, moves on through the left ventricle and leaves through the aorta.

Does the circulatory system word search have an answer key?

Yes. It prints on two pages, Letter or A4: the puzzle, then its key. With Show clues, not words ticked, Venule prints as "A very small vein that lets blood return from the capillary beds."

All 98 words

Parts of the Heart 22

Parts of the Heart, continued

Blood Vessels 23

Parts of Blood 28

How Blood Circulates 25

How it works

The heart and the vessels

The blood and its two circuits

Questions and answers

More tools