Types of Circulation and Circulatory Systems




Types of Circulation and Circulatory Systems


Class :


Term :

First Term

Week :

Week 4

Instructional Teaching Materials :

  • Photos of plants and animals
  • Sample alimentary canal of animal



  • Scheme of Work
  • On-line Information
  • Textbooks
  • Workbooks

Earlier Tutorials 

The pupils have earlier information on

Materials that are Transported in Plants and Animals

that was beforehand taught as a topic before this specific lesson


Behavioural Objectives :  On the conclusion  of this lesson, the learners will likely be succesful to

  • Say The Forms of Circulation and Circulatory Systems
  • Explain The Mechanism of Transportation in Higher Animals
  • Differentiate  between Open and Closed Circulatory Programs
  • Spotlight The Mechanism of Transportation in Multicellular Organisms
  • Clarify The Process Absorption of Water and Mineral Salts in Higher Crops






  1. Which means of Circulatory System
  2. Sorts of Circulation and Circulatory Programs
  3. Mechanism of Transportation in Increased Animals
  4. Variations between Open and Closed Circulatory Programs
  5. Mechanism of Transportation in Multicellular Organisms
  6. Absorption of Water and Mineral Salts in Increased Crops


Which means of Circulatory System

Circulatory system is the continual circulation of blood across the physique, involving the guts and the blood vessels.

Types of Circulation and Circulatory Programs

Forms of Circulatory Programs

  1. Open circulatory system
  2. Closed circulatory system

Varieties of Circulation

  1. Single circulation
  2. Double circulation
  3. Systemic circulation
  4. Pulmonary circulation

Mechanism of Transportation in Greater Animals

As a result of the repeated contractions of the guts, the blood circulatory system (i.e., arteries, capillaries and veins) all through life. All mammals have double circulation. These are the systemic (physique) circulation and pulmonary circulation.

  1. Systemic (physique) circulation wherein blood is carried from the left ventricle to all physique components besides the lungs and again to the proper auricle.
  2. Pulmonary circulation wherein blood is carried from the proper ventricle to the lungs via the pulmonary veins.

The guts like different organs has a blood provide. The coronary arteries, which department from the aorta close to the guts, carry blood to the guts muscle mass. The circulation of blood via these muscle mass is known as coronary circulation.

The guts continues to beat repeatedly all through the life and pump blood to the 2 essential circulations and the coronary circulation. When the physique is at relaxation, regular coronary heart beats about 70 to 72 occasions per minute. The speed of the guts beat will increase when one could be very lively or excited. The liver is the one organ within the physique that receives blood by the hepatic artery and hepatic portal vein. The hepatic portal vein carries blood wealthy in digested meals from the abdomen and small intestines into the liver. The hepatic portal vein carries blood from the liver into the inferior vena cava.


Frontal Part of the Coronary heart

The human coronary heart is a hole, pear-shaped organ concerning the measurement of a fist. The guts is made from muscle that rhythmically contracts, or beats, pumping blood all through the physique. Oxygen-poor blood from the physique enters the guts from two giant blood vessels, the inferior vena cava and the superior vena cava, and collects in the proper atrium. When the atrium fills, it contracts, and blood passes via the tricuspid valve into the proper ventricle. When the ventricle turns into full, it begins to contract, and the tricuspid valve closes to forestall blood from shifting again into the atrium. As the proper ventricle contracts, it forces blood into the pulmonary artery, which carries blood to the lungs to choose up contemporary oxygen. When blood exits the proper ventricle, the ventricle relaxes and the pulmonary valve shuts, stopping blood from passing again into the ventricle. Blood returning from the lungs to the guts collects within the left atrium. When this chamber contracts, blood flows via the mitral valve into the left ventricle. The left ventricle fills and begins to contract, and the mitral valve between the 2 chambers closes. Within the closing part of blood circulation via the guts, the left ventricle contracts and forces blood into the aorta. After the blood within the left ventricle has been pressured out, the ventricle begins to calm down, and the aortic valve on the opening of the aorta closes.


Blood Vessels

Blood vessels flow into blood via the physique. The three main varieties of blood vessels are the arteries, veins, and capillaries. Arteries carry blood away from the guts, whereas veins carry blood towards the guts. Capillaries type on the junction between arteries and veins and they’re the one blood vessel to come back into direct contact with tissue cells. Oxygen, vitamins, and different substances transported in blood via the arteries cross via skinny capillary partitions into tissue cells. Wastes and different merchandise of mobile metabolism move from cells again via the capillary partitions and into veins. The partitions of arteries and veins are composed of three tunics (layers) that encompass a central opening referred to as a lumen, via which blood flows. The innermost layer is the tunica intima, composed of endothelial cells that type a slick lining that minimizes friction as blood strikes via the lumen. The center layer is the tunica media. Composed of clean muscle cells and sheets of elastic tissue, this layer permits the lumen to slim or widen to manage blood circulation within the physique. The tunica adventitia types a protecting outer layer of the blood vessel wall and it additionally anchors the blood vessel to surrounding buildings.


The Circulatory System

Differences between Open and Closed Circulatory Methods

1It’s found in some molluscs,
arthropods and lower animals.
Present in annelids, vertebrates
and a few invertebrates.
2No small blood vessels or
capillaries connecting arteries
with veins.
Minute blood capillaries unite
the smaller arteries with the veins.
3Blood leads to blood areas
(haemocoels) throughout the physique.
Blood flows through the arteries,
veins and capillaries.
4Blood bathes the main organs
and tissues instantly.
Fluids with vitamins attain the
physique tissues from the capillaries
as tissue fluids and lymph.
5Blood returns on to the guts.Blood returns to through the veins.

Mechanism of Transportation in Multicellular Animals

In lots of multicellular animals, supplies are transported from one a part of the physique to a different in a circulatory system. There are two essential circulatory techniques in animals, specifically open and closed techniques.  Within the open circulatory system, the blood vessels go away the guts however find yourself in blood areas referred to as haemocoels throughout the physique. The blood is available in contact with the body cells after which it’s despatched again to the guts; instance is present in arthropods and in some molluscs.

Within the closed circulatory system, blood is restricted to branching blood vessels. Via them, blood is pumped to the physique by a number of hearts. That is discovered in the annelids and vertebrates. In unicellular organisms, equivalent to spirogyra, vitamins, gasses and metabolic wastes transfer out and in of their physique by diffusion. In just a few different unicellular organisms, equivalent to paramecium, meals substances in meals vacuoles are carried alongside a selected route by a course of referred to as cyclosis.

In vascular crops (pteridophytes, gymnosperms and angiosperms), there’s a circulatory system wherein supplies are carried to and from all physique components. The circulatory system consists of vascular tissues, which is a system of slim tubes. Crops which have vascular tissues are referred to as vascular crops. The vascular tissue consists of compact strands referred to as vascular bundles. Every bundle consists of the xylem close to the stem centre and the phloem in direction of the outer floor of the stem. The cambium is normally present in between the xylem and the phloem within the dicotyledonous roots and stems, and monocotyledonous crops shouldn’t have cambium. Crops additionally make use different mechanisms of transportation equivalent to root stress, transpiration stream, and protoplasmic streaming which happen in each crops and animals.

Absorption of Water and Mineral Salts in Increased Crops

Crops want adequate portions of many materials, that are transported in them. These embrace water, mineral salts and manufactured meals. In aquatic, unicellular and easy multicellular crops, gases enter and go away their cells by diffusion. Water enters the cells of those crops by osmosis, whereas manufactured meals and wastes are transported by diffusion. In flowering crops, the gases are absorbed primarily via stomata within the leaves and lenticels within the stems, whereas mineral salts are absorbed via the roots system.

Contained in the crops, gases transfer by diffusion. They’re at all times dissolved in water of the moist cell partitions earlier than coming into the cells. Water, mineral salts and soluble meals are transported in vascular tissues.

Definition of Diffusion

Diffusion is the motion of molecule from the area of upper focus to the area of decrease focus. It will possibly happen in liquid, however it’s sooner in gaseous medium.

Examples of Diffusion in Dwelling Membranes (Needs for Diffusion)

Some examples of diffusion in dwelling membrane are:

  1. Absorption of vitamins, e.g. mineral salts uptake in roots.
  2. Change of gases within the cells or tissue e.g. Oxygen and Carbon (iv) oxide trade via the stomata.
  3. Supplies transport throughout the cells
  4. Excretion of waste product e.g. diffusion of carbon (iv) oxide into the alveoli.

The Precept Of Diffusion

Graham’s regulation of diffusion states that the rate of diffusion of a gasoline is inversely proportional to the sq. root of the density.

Therefore, lighter gases can diffuse via heavier gases, e.g. hydrogen sulphide has subtle via air.

Significance of Diffusion

When molecules are erratically distributed within the cell, diffusion tends to equalize the distribution.

Definition Of Osmosis

Osmosis on the hand is instantly reverse diffusion. It’s outlined because the motion of solvent molecules (normally water) from an answer of decrease focus to a extra concentrated answer via a differentially permeable or semi-permeable membrane to be able to preserve an ionic equilibrium. Osmosis is subsequently a particular type of diffusion.

Thus osmosis could also be outlined as the online motion of water from space of low D.PD. or greater water focus via an space of excessive D.P.D.or low water focus via a semi-permeable membrane.

D.P.D.: Diffusion stress deficit, this can be outlined as distinction in water potential on either side of the semi-permeable membrane.

Examples of Osmosis in Residing Membranes (Residing Cells)

Some examples of osmosis in dwelling membrane (dwelling cells) are:

  1. Absorption of vitamins or uptake of vitamins or water.
  2. Plasmolysis of cells or shrinking of cells in hypertonic answer.
  3. Turgidity of cells.
  4. Haemolysis of crimson blood cells/bursting of animal cells in hypotonic options.

In osmosis, water strikes right into a stronger answer (the sugar answer in (E) via a dwelling materials which acts as a semi-permeable membrane.

Examples of Osmosis in Crops: Want for Osmosis

  1. Water absorption by the roots.
  2. Plasmolysis of plant cells.
  3. Motion of water from one cell to a different in crops.
  4. Upkeep of turgor pressure in plant cells.
  5. Opening and shutting of stomata.

Examples of Osmosis in Animals

  1. Re-absorption of water by kidney tubules.
  2. Haemolysis and crenation of crimson blood cells.
  3. Osmo-regulation in Amoeba and Paramecium.
  4. Upkeep of form of mammalian cells within the surrounding tissue fluid.

Significance Of Osmosis

Osmosis is concerned with the transport of supplies between cells.






The topic is obtainable step-by-step


Step 1:

The subject teacher revises the sooner issues


Step 2.

He introduces the topic new topic


Step 3:

The class coach permits the pupils to current their very personal examples and he corrects them when the desires come up



Conclusion :


The class coach wraps up or conclude the lesson by giving out temporary observe to summarize the topic that he or she has merely taught.

The class coach moreover goes spherical to ensure that the notes are correctly copied or correctly written by the pupils.

He or she does the required corrections when and the place  the desires come up.




  1. Outline circulatory system.
  2. Record and clarify the varieties of circulatory techniques.
  3. Differentiate between open and closed circulatory techniques.





The topic wraps up the subject by giving the learners a complete notice and she or he makes certain that the learners copy the notes accurately . She or he marks the notes and he does the mandatory corrections