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tiny sacs of lung tissue specialized for the movement of gases between air and blood

anal sphincter

The valve that controls the release of feces from the recturm. It has an internal part made of smooth muscle (thus involuntary) and an external part made of skeletal muscle (thus voluntary).


opening through which wastes leave the digestive tract

bile duct

Tube that carries bile from the liver and gallbladder to the intestine.


the paired ventilatory tubes of a vertebrate that branch into each lung at the lower end of the trachea


Derived from tertiary bronchi. Walls made of smooth muscle. Subdivide into alveolar ducts that are derived from respiratory bronchioles.

cardiac sphincter

the valve between the distal end of the esophagus and the stomach


first part of the large intestine

coronary vessels

supply the heart muscle (myocardium) with its blood supply


a flat muscle that seperates the chest from the abdominal cavity


belonging to or on or near the back or upper surface of an animal or organ or part


first part of the small intestine


a flap of cartilage that covers the windpipe while swallowing


muscular tube that moves food from the pharynx to the stomach

gall bladder

stores bile produced by the liver until it is needed in the duodenum


opening between the vocal cords in the larynx

hard palate

The hard front portion of the roof of the mouth and floor of the nasal cavity

inferior vena cava

receives blood from lower limbs and abdominal organs and empties into the posterior part of the right atrium of the heart


Middle portion of the small intestine

large intestine

the last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body


voice box; passageway for air moving from pharynx to trachea; contains vocal cords

left atrium

the left upper chamber of the heart that receives blood from the pulmonary veins

left ventricle

the chamber on the left side of the heart that receives arterial blood from the left atrium and pumps it into the aorta


organ that makes bile to break down fats; also filters poisons and drugs out of the blood


supportive membrane surrounding internal organs and attaching to the body wall


thick middle muscle layer of the heart; pumps blood through the circulatory system


small rough elevations on tongue and roof of mouth; contain taste buds

pericardial membrane

this surrounds and protects the heart


the passage to the stomach and lungs

pulmonary circuit

carries blood to the lungs for gas exchange and returns it to the heart

pyloric sphincter

ring of muscle that guards the opening between the stomach and the duodenum


A short tube at the end of the large intestine where waste material is compressed into a solid form before being eliminated

right atrium

The upper right chamber of the heart, where deoxygenated blood is received from the vena cava and then sent to the right ventricle.

right ventricle

the chamber on the right side of the heart that receives venous blood from the right atrium and pumps it into the pulmonary trunk

salivary glands

glands of the mouth that produce saliva, a digestive secretion

sinus cavity

(air filled pocket with mucous membrane) - ducts drain into internal nose; help with conditioning of incoming air.

skeletal muscle

Vouluntary, striated muscle that moves bones, works in pairs and is attatched to bones by tendons

small intestine

digestive organ in which most chemical digestion takes place

smooth muscle

a muscle that contracts involuntary and is found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart)

soft palate

muscular posterior (back) portion of the palate


food is churned by muscles here, chemicles like hydrochloric acid and pepsin added and forms a liquid called chyme

superior vena cava

receives blood from the head and arms and chest and empties into the right atrium of the heart

systemic circuit

Circuit of blood that carries blood between the heart and the rest of the body.


hard bony projections in the jaws for chewing food

thoracic cavity

the cavity in the vertebrate body enclosed by the ribs between the diaphragm and the neck and containing the lungs and heart


a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity


membranous tube with cartilaginous rings that conveys inhaled air from the larynx to the bronchi

umbilical artery

circulatory; carries waste and deoxygenated blood from the fetus to the mother

umbilical vein

A vein in the umbilical cord; brings nutrient blood from the mother to the fetus.


nearest to or facing toward the axis of an organ or organism

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