aorota Flashcards
What are the major parts of the aorta, and how is it described in the body?
The aorta is the largest artery in the body, about the size of a garden hose in adults (with an internal diameter similar to the diameter of the thumb).
It begins at the left ventricle of the heart and is called the ascending aorta as it springs upward.
The aorta then arches to the left, forming the aortic arch.
It continues downward through the thorax as the thoracic aorta, following the spine.
It passes through the diaphragm into the abdominopelvic cavity, where it becomes the abdominal aorta.
What are the major branches of the aorta, and which organs do they serve?
The aorta has several branches, each serving specific body regions and organs.
Renal artery: Supplies the kidneys.
Brachial artery: Supplies the arms (upper limbs).
Coronary arteries: Supply the heart muscle.
Femoral artery: Supplies the thigh and legs (lower limbs).
Ulnar artery: Supplies the forearm and hand.
The names of these arteries typically reflect the body region or organ they supply, making it easier to learn their functions.
What are the branches of the ascending aorta, and what do they serve?
The only branches of the ascending aorta are the right (R.) coronary artery and the left (L.) coronary artery.
These arteries supply blood to the heart muscle itself.
Q: What are the arterial branches of the aortic arch, and which organs do they serve?
Brachiocephalic trunk (first branch of the aortic arch):
Splits into the right common carotid artery (further branches into the right internal and external carotid arteries) and the right subclavian artery.
Left common carotid artery (second branch off the aortic arch):
Divides into the left internal carotid artery (serves the brain) and the left external carotid artery (serves the skin and muscles of the head and neck).
Left subclavian artery (third branch of the aortic arch):
Gives off the vertebral artery (serves part of the brain).
The left subclavian artery continues into the axillary artery, which becomes the brachial artery in the arm.
The brachial artery splits at the elbow into the radial and ulnar arteries, which supply the forearm.
What are the arterial branches of the thoracic aorta, and what do they serve?
Intercostal arteries (10 pairs):
Supply the muscles of the thorax wall.
Bronchial arteries:
Supply the lungs.
Esophageal arteries:
Supply the esophagus.
Phrenic arteries:
Supply the diaphragm.
: What are the arterial branches of the abdominal aorta, and what do they supply?
Celiac trunk (first branch):
Left gastric artery: Supplies the stomach.
Splenic artery: Supplies the spleen.
Common hepatic artery: Supplies the liver.
Superior mesenteric artery:
Supplies most of the small intestine and the first half of the large intestine (colon).
Renal arteries (right and left):
Supply the kidneys.
Gonadal arteries (right and left):
Ovarian arteries (females): Supply the ovaries.
Testicular arteries (males): Supply the testes.
Lumbar arteries:
Serve the abdomen and trunk walls.
Inferior mesenteric artery:
Supplies the second half of the large intestine.
Common iliac arteries (right and left):
Each divides into internal iliac artery (supplies pelvic organs) and external iliac artery (enters the thigh).
Femoral artery: Serves the thigh.
Popliteal artery: Serves the knee and splits into anterior tibial and posterior tibial arteries, which serve the leg and foot.
Dorsalis pedis artery: Supplies the dorsum of the foot (often palpated for circulatory issues).
Where do major veins of the systemic circulation converge, and what is their function?
Major veins converge into the vena cava (superior and inferior), which empty into the right atrium of the heart.
Veins draining the head and arms: Empty into the superior vena cava.
Veins draining the lower body: Empty into the inferior vena cava.
Q: What veins drain into the superior vena cava, and what is the direction of blood flow?
Veins draining into the superior vena cava are listed in a distal-to-proximal direction, meaning they are ordered from furthest (distal) from the heart to closest (proximal) to the heart.
These veins carry deoxygenated blood from the upper body and return it to the right atrium of the heart.
: What veins drain into the superior vena cava, and what do they drain?
Radial and ulnar veins (deep veins) drain the forearm and unite to form the brachial vein, which empties into the axillary vein.
Cephalic vein drains the lateral aspect of the arm and empties into the axillary vein.
Basilic vein drains the medial aspect of the arm and empties into the brachial vein.
Median cubital vein connects the cephalic and basilic veins at the elbow and is often used for blood withdrawal.
Subclavian vein receives blood from the arm (via axillary vein) and from the head (via external jugular vein).
Vertebral vein drains the posterior head.
Internal jugular vein drains the dural sinuses of the brain.
Brachiocephalic veins (right and left) receive venous blood from the subclavian, vertebral, and internal jugular veins. These veins merge to form the superior vena cava, which enters the heart.
Azygos vein drains the thorax and enters the superior vena cava just before it enters the heart.
Q: What are the two main pairs of arteries that supply blood to the brain, and what is the importance of continuous blood flow?
Internal carotid arteries and vertebral arteries supply the brain with blood.
A continuous blood supply is crucial for brain function because even a brief lack of blood can cause brain cells to die.
How do the internal carotid arteries supply the brain, and what do they branch into?
The internal carotid arteries are branches of the common carotid arteries.
They travel through the neck and enter the skull through the temporal bone.
Inside the cranium, they divide into the anterior cerebral artery and the middle cerebral artery, which supply most of the cerebrum.
How do the vertebral arteries supply the brain, and what do they form inside the skull?
The paired vertebral arteries originate from the subclavian arteries at the base of the neck.
Inside the skull, the vertebral arteries merge to form the basilar artery.
The basilar artery serves the brain stem and cerebellum as it travels upward.
At the base of the cerebrum, the basilar artery splits into the posterior cerebral arteries, which supply the posterior part of the cerebrum.
Q: What is the Circle of Willis, and what is its function?
The Circle of Willis is a ring of connecting blood vessels at the base of the brain.
It is formed by small communicating arterial branches between the anterior and posterior blood supplies of the brain.
The Circle of Willis provides a backup route for blood flow, ensuring that if one part of the arterial system is blocked or impaired, blood can still reach brain tissue.
What is the hepatic portal circulation, and why is it important?
The hepatic portal circulation involves veins that drain the digestive organs, spleen, and pancreas and deliver the blood to the liver via the hepatic portal vein.
After eating, the blood in the hepatic portal vein contains high levels of nutrients, which the liver processes.
This system allows the liver to regulate glucose, fat, and protein levels in the blood and detoxify the blood by removing toxins.
Blood is slowly filtered through the liver, where nutrients are processed and stored, and then drained through the hepatic veins into the inferior vena cava.
: What are the major vessels involved in the hepatic portal circulation, and how do they function?
The major vessels of the hepatic portal circulation include:
Inferior mesenteric vein: Drains the terminal part of the large intestine into the splenic vein.
Splenic vein: Drains the spleen, pancreas, and left side of the stomach.
Superior mesenteric vein: Drains the small intestine and the first part of the colon, joining with the splenic vein to form the hepatic portal vein.
Left gastric vein: Drains the right side of the stomach directly into the hepatic portal vein.
These veins deliver blood containing absorbed nutrients from the digestive organs to the liver for processing before entering the systemic circulation.
