Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

NEET: Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

The document Introduction: Circulatory System Notes | Study Biology Class 11 - NEET is a part of the NEET Course Biology Class 11.
All you need of NEET at this link: NEET

What is Circulatory System?

An expanded pipeline system is present in the human body. It is called the closed circulatory system. 

A continuous chemical exchange of materials between the animal body and environment among different tissues of the body is done through this system. In this way, digested nutrients from the digestive system, oxygen from respiratory organs, hormones from endocrine glands are distributed to all the cells of the body. Also, the transport of CO2 from body cells to respiratory organs, NH3, urea etc. excretory substances to excretory organs are the function of the circulatory system. The whole circulatory system is formed by the mesoderm of the embryo. Except the inner lining of blood vessels and heart which are of endodermal origin.Human HeartHuman Heart

Types of Circulatory System on basis of Complexity and Evolution

Open type

Closed type

1) Blood is filled in the coelomic channel and sinus coelom is called haemocoel. Fluid is called hemolymph.

1) Blood circulates in closed vessels.

2) Tissues are in direct contact with circulating fluid. eg. Arthropodes, non cephalopod molluscs.

2) Tissues are not in direct contact with circulating fluid. e.g. Annelids, Cephalopod molluscs, Chordates.

Types of Circulatory System on the basis of Circulating Fluid

In human beings (on the basis of circulating fluid) two types of circulatory system are observed.

  • Blood circulatory system: It consists of Blood, Blood vessels, Heart.
  • Lymphatic system: It consists of lymph, lymph capillaries, lymph vessels, lymph nodes, lymphoid tissues/organs.

The study of blood vascular system or circulatory system is called Angiology.

William Harvey is known as the father of angiology. He called the heart the "Pumping station of the body".

Circulation of Blood

Single Circuit

Example: Fishes

 

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

Double Circuit

Example: Man, Rabbit

 

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

Transitional Type Circuit

Two circuits are not completely separate 

Example: FROG 

Blood mixes in ventricles Evolutionary sequence is present in vertebrates.

  • Fishes have a tubular "Venous-Heart" In their heart, deoxygenated blood enters from one side and from the other side enters inside the gills for purification. This is called the "Single Heart Circuit".
  • In amphibians (like Frog) and Reptiles, the auricles are divided into right and left. The right auricle gets impure and the left auricle gets pure blood from the body. But only 1 ventricle is present or is incompletely divided so after coming here the pure and impure blood mix up.
  • In some reptiles (Crocodile, Gavialis and Alligator) and in all birds and mammals the heart is divided into 2 auricles and 2 ventricles so while circulating inside the heart the pure and impure blood remain separated. The right portion of the heart collects impure blood from the body and sends it to the lungs for purification, while the left portion takes pure blood from the lungs and distributes it to the whole body.

The right portion of the heart is called the "Pulmonary-Heart" and the left portion is termed as the "Systemic-heart". This is termed as "Double Circulation of Heart".because the blood has to pass through the heart twice before being delivered to systemic organs. Types of heart on the basis of type of blood which it receives:

  • Venous/Brachial (fishes)
  • Arterial (prawn)
  • Arteriovenous (lung fishes, tetrapods)

Path of Blood in Double Circuit (Man) 

It was first discovered by "William Harvey".

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

 Path of Blood in Double CircuitPath of Blood in Double Circuit

Location of HeartLocation of Heart

The document Introduction: Circulatory System Notes | Study Biology Class 11 - NEET is a part of the NEET Course Biology Class 11.
All you need of NEET at this link: NEET
254 videos|371 docs|345 tests

How to Prepare for NEET

Read our guide to prepare for NEET which is created by Toppers & the best Teachers

Download free EduRev App

Track your progress, build streaks, highlight & save important lessons and more!

Related Searches

practice quizzes

,

Extra Questions

,

Summary

,

Sample Paper

,

Semester Notes

,

study material

,

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

,

Free

,

pdf

,

mock tests for examination

,

past year papers

,

Viva Questions

,

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

,

Important questions

,

shortcuts and tricks

,

Introduction: Circulatory System Notes | Study Biology Class 11 - NEET

,

Exam

,

ppt

,

Previous Year Questions with Solutions

,

video lectures

,

Objective type Questions

,

MCQs

;