Circulatory system - developmental changes, Biology

Assignment Help:

Circulatory System - Developmental Changes

We have learnt that throughout foetal life, gas exchange takes place, only through the placenta and not through lungs. Therefore, the foetus has various features in its circulatory systems that are not present in an adult. Diagram is a diagrammatic representation of foetal and infant circulation. In the foetus the oxygenated blood flowing back through the umbilical vein mainly bypasses the liver and goes to the right atrium.

2238_Circulatory System.png

Figure: Changes After Birth in Circulatory System

The blood then passes to the left atrium directly by an opening called foramen ovale. From the left atrium the blood flows to the left ventricle that sends the blood to the head and rest of the body. Blood returning from the head moves by the right atrium to the right ventricle which then does not pump the blood to the lungs but to a shunting vessel the ductus arteriosus that connects along with the descending aorta. A pair of umbilical arteries branch off from the aorta and carry deoxygenated blood to the placenta. At birth the umbilical artery and vein collapse while the cord is tied or the placenta separates, the result of it (here is negative pressure in the right atrium and blood flows back from the left atrium to the right. The flow causes the one way valve to close in the foramen ovale. Thus the left and right atria are separated. The shunting vessels which bypassed the liver and the lungs also collapse and adult pattern of circulation starts. The entire process takes place within a few hours of birth, though the permanent closure of foramen ovale may take up to a year.


Related Discussions:- Circulatory system - developmental changes

Expalain briefly vitamin A, Vitamin A (Retinol) Purified vitamin A is a...

Vitamin A (Retinol) Purified vitamin A is a viscous yellowish oil. It is freely soluble in most organic solvents such as methanol, ether, acetone, chloroform and petroleum ethe

Define japanese criteria for functional foods, Define Japanese criteria for...

Define Japanese criteria for functional foods? The Japanese criteria for functional foods include: They are food (not capsules, pills/powder) on the basis of naturally o

Explain the communication process, Q. Explain the communication process? ...

Q. Explain the communication process? Communication is a process by which information is exchanged between individuals through a common system of symbols, signs, or behavior. C

Define triple sugar iron - carbohydrate utilization pattern, Define Triple ...

Define Triple Sugar iron - Carbohydrate Utilization Pattern? Triple sugar iron (TSI) agar is used to observe carbohydrate utilization pattern. The medium contains 1% concentr

What is the route of the ingested food, What is the route of the ingested f...

What is the route of the ingested food from swallowing until the duodenum? Unless reaching the duodenum the food enters the mouth, passes the pharynx, goes down the esophagus a

What are the moderate intensity exercises, Q. What are the moderate intensi...

Q. What are the moderate intensity exercises? - Walking for 1/2% hr or jogging - Biking leisurely for 1/2 hr. - Playing tennis, swimming, gardening, golfing - Vacuumin

Human factor theory - accident causation, Human Factor Theory - Accident Ca...

Human Factor Theory - Accident Causation This theory of accident causation suggests that a chain of events caused by human error is the cause of accident. The chain of events

Pathophysiology and assessment of purpura, Pathophysiolog y   Normal...

Pathophysiolog y   Normally the platelets are formed from megakaryocytes (stem cells) in the.  bone marrow. These cells mature, fragment and are released in  the blood strea

Smoke print, Write a brief theory about smock print?

Write a brief theory about smock print?

Will sedantary lifestyle increased risk for cad, Q. Will Sedantary Lifestyl...

Q. Will Sedantary Lifestyle increased risk for CAD? A sedantary life style is associated with increased risk for CAD. Sedentary persons have almost double the risk for CAD deat

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd