science

Umbilical vein

Umbilical vein is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Umbilical vein rather than just read about it. In short: The umbilical vein is a vein present during fetal development that carries oxygenated blood from the placenta into the growing fetus. The umbilical vein provides convenient access to the central circulation of a neonate for restoration of blood volume and for administration of glucose and drugs.

Key takeaways

Umbilical vein belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Umbilical vein to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Umbilical vein from memory before moving on to harder problems.

Reference excerpt

The umbilical vein is a vein present during fetal development that carries oxygenated blood from the placenta into the growing fetus. The umbilical vein provides convenient access to the central circulation of a neonate for restoration of blood volume and for administration of glucose and drugs. The blood pressure inside the umbilical vein is approximately 20 mmHg.

Fetal circulation The unpaired umbilical vein carries oxygen and nutrient rich blood derived from fetal-maternal blood exchange at the chorionic villi. More than two-thirds of fetal hepatic circulation is via the main portal vein, while the remainder is shunted from the left portal vein via the ductus venosus to the inferior vena cava, eventually being delivered to the fetal right atrium.

Closure Closure of the umbilical vein usually occurs after the umbilical arteries have closed. This prolongs the communication between the placenta and fetal heart, allowing for a sort of autotransfusion of remaining blood from the placenta to the fetus. Within a week of birth, the neonate's umbilical vein is obliterated and is replaced by a fibrous cord called the round ligament of the liver (also called ligamentum teres hepatis). It extends from the umbilicus to the transverse fissure, where it joins with the falciform ligament of the liver to separate segment 4 from segments 2 and 3 of the left hepatic lobe.

Recanalization Under extreme pressure, the round ligament may reopen to allow the passage of blood. Such recanalization may be evident in patients with cirrhosis and portal hypertension. Patients with cirrhosis experience rapid growth of scar tissue in and around the liver, often functionally obstructing nearby vessels. Vessel occlusion increases vascular resistance and therefore leads to hypertension. In portal hypertension, the vessels surrounding the liver are subjected to abnormally high blood pressure—so high, in fact, that the force of the blood pressing against the round ligament is sufficient to recanalize the structure. This leads to a condition called caput medusae.

Catheterization A newborn baby has a patent umbilical vein for at least a week after birth. This umbilical vein may be catheterised for ready intravenous access. It may be used as a site for regular transfusion in cases of erythroblastosis or hemolytic disease. It also provides a route for measuring central venous pressure.

Additional images

See also Human umbilical vein graft Ductus venosus

References

External links Embryology at Temple Heart98/heart97a/sld020

Illustrations

Worked examples

Example 1 — a first encounter with Umbilical vein

Start with the simplest possible case. Write down what Umbilical vein claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Umbilical vein before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Umbilical vein ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Umbilical vein

In research: Umbilical vein appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Umbilical vein in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Umbilical vein is common in secondary-school and first-year university syllabi. It links to neighbouring topics Embryology of cardiovascular system, Veins, so understanding it makes those chapters shorter.
In everyday life: Look for Umbilical vein outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Umbilical vein” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Umbilical vein in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Umbilical vein means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Umbilical vein out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Umbilical vein in simple terms?

Why does Umbilical vein matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Umbilical vein?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Umbilical vein.