circulatory system

2. Circulatory
SYSTEM
• Group Members
• Ariba Sheikh
• Maria Zafar
• Syeda Bushra Mansoor
• Syeda Faiza Mansoor

3. Table of Contents:
 Definition of Circulatory System
 Types of Circulatory System
 Introduction to Blood.
 Functions of Blood.
 Introduction to Blood Vessels.
 Definition and Structure of Heart.
 Pulmonary Circuit.
 Systematic Circuit.

4. Definition Of
Circulatory System:
• The circulatory system, also called
the cardiovascular system or
the vascular system, is an organ
system that permits blood to
circulate and transport nutrients
and blood cells to and from
the cells in the body to provide
nourishment.
• It helps in fighting
diseases, stabilize temperature ,pH
level and maintain homeostasis..

5. Types of Circulatory
System
There are two types
of circulatory system.
• Open types
circulatory system.
• Close type
circulatory system.

6. Open type circulatory system:
In many invertebrates such as arthropods and
molluscs etc. the blood does not flow inside
the blood vessels, inside it remains filled in the
open tissue spaces called sinuses,
So this tissues of the body are virtually floating
in and in directly contact with the blood.
After exchange of materials with the tissues, it
enters the pumping organ or the heart which
pumps the blood into the blood vessels. This
vessels again drain out the blood into the
sinuses, hence it is kept into circulation.

7. Examples of Open
type Circulatory
System:
1) Molluscs:
• Mollusc is an
invertebrate which
includes snails, slugs,
cuttlefishes, and
octopuses. They have a
soft body and live in
aquatic or damp
habitats.

8. Examples of Open
type Circulatory
System:
• (2) Arthropods:
Arthropod is an
invertebrate animal
having an
exoskeleton such as
an insects, spiders,
butterflies or
scorpions.

9. Closed Type Circulatory System
• The circulatory systems of all vertebrates, as
well as of annelids and
chordates, are closed, just as in humans.
• In this system, blood flows inside the closed
tubular blood vessels and does not come in
direct contact with the tissues. This system
consists of a pumping organ the heart, the
blood vessels (arteries, veins and capillaries)
and blood. This system is much more
efficient and rapid.

10. Examples of Closed type
Circulatory System:
1) Annelids:
Annelid is a worm, such as
earthworms or leach.

11. Examples of Closed type Circulatory System:
2)Chordates:
Chordate is an animal,
comprising the
vertebrates.

12. Blood
• A special kind of tissue which
circulates in fluid form in the body is
known as blood.
• There is no substitute for blood. It cannot
be made or manufactured. Generous blood
donors are the only source of blood for
patients in need of a blood transfusion.
Composition:
• Blood is composed of following things;
• Fluid part
• The plasma
• A cellular part
• The corpuscles

13. Functions of the Blood:
• Transport of gases to the tissues (oxygen) and
from the tissues (carbon dioxide).
• Defends the body by killing germs, which
somehow enter the body.
• Transport of nutrients (such as amino acids,
glucose, fatty acids) from the gut (digestive
system) to all parts of the body.
• Transport of nitrogenous waste from tissues to
excretory organs (such as kidney).
• Transport of hormones (such as sex hormones,
insulin) from endocrine glands to their target
organs.
• Maintenance of uniform body temperature
and pH level.
• Makes a clot by itself to stop bleeding.

14. Plasma:
• Plasma is the liquid portion of your
blood. Plasma transports water and
nutrients to your body’s tissues.
Composition
• Yellowish in colour or color-less and is
made up mostly of water(90 to 92%)
• Contains proteins, sugars, hormones,
amino acids, salts, glucose, enzymes,
wastes, gases etc.

15. Corpuscles/Blood Cells:
Corpuscles or blood cells are
of two types,
• Red blood cells or
corpuscles
• White blood cells or
corpuscles.

16. R.B.Cs and W.B.Cs:
Red blood Corpuscles (R.B.Cs):
 Red blood corpuscles are also called erythrocytes are
circular , disc like ,biconcave cells in mammals RBCs
contain haemoglobin and protein that carries
oxygen.
 Each RBC lives for about 4 months. Each day, the
body makes new RBCs to replace those that die or
are lost from the body. RBCs are made in the inside
part of bones called the bone marrow.
White blood Corpuscles (W.B.Cs):
 W.B.Cs are colorless, irregular in shape ,nucleated
and larger than R.B.Cs. WBCs, also called leukocytes,
are a key part of the immune system.
 W.B.Cs also known as ‘police of the body’ because
they protect the body killing germs such as bacteria
and virus
 Some types of WBCs make antibodies, which are
special proteins that recognize foreign materials and
help the body get rid of them.They fewer in number
than R.B.Cs in the body.

17. Platelets:
o Platelets (also called thrombocytes,
say: THROM-buh-sytes) are tiny
oval-shaped fragments of a large
cell
o It helps in the clotting process
o When a blood vessel breaks,
platelets gather in the area and help
seal off the leak.
o Platelets work with proteins called
clotting factors to control bleeding
inside our bodies and on our skin.
o Platelets survive only about 9 days
in the bloodstream and are
constantly being replaced by new
platelets made by the bone marrow.

19. Heart:
 A muscular, pumping
organ located in thorax
in the body of Living
things is known as
Heart.
 Its protective bag is
called pericardium

20. Structure and Function of
Heart
• Externally it is conical in shape,
internally it consists of four camber,
upper two thin walled called atria,
lower two thick walled called ventricles.
• It consists of following parts:
• Vena cava carrying deoxygenated blood
into the heart.
• Aortic valve is between the left
ventricle and the aorta.
• Tricuspid valve in between right atrium
and ventricle.

21. Structure and Function OF
Heart
• Mitral valve in between left atrium and
ventricle.
• The main function of these valves is that it
prevents from back flow of blood from
ventricles to atrium.
• Superior vena cava bring blood into heart
from head and neck while inferior vena cava
bring blood into heart from body.
• Pulmonary artery takes blood to the lungs for
oxygenation while pulmonary veins bring
blood into heart from lungs.
• Aorta main artery taking blood to the body.

23. Blood Vessels:
 The blood vessels are tubes in
which blood circulates in the body
in a closed circulatory system.
 These are the three types;
 arteries, capillaries and vein
through which these vessels are
travel.
 Blood vessels are like little pipes
that connect to the heart.

24. Arteries:
• Arteries carry oxygenated blood are known as
arteries.
• They are thick walled and more elastic than veins.
• When an artery enters in an cores ponding organs,
it divides up smaller branches or arterioles.
• The walls of an artery is composed of three layers,
• An inner layer of endothelial cell.
• A thick layer of smooth muscles and elastic fibers.
• Outer layer of connective tissue or elastic fibers.
• The blood in arteries is bright red in color because
it contains oxygen.
• The largest arteries are closest to the heart and are
about the diameter of your thumb.
• The smallest arteries, called arterioles, are less
than 0.5 mm in diameter, meaning they are so tiny
that they are barely visible to the human eye.

25. Veins:
• Vein are the blood vessels that
brings blood back to heart.
• They are formed by the union of
smaller branches called venules.
• Veins are thin walled and less
elastic than arteries.
• The blood flow in vein is slower
and uniform as compared to
artery. Like artery, the walls of a
vein are also composed of the
same three but less muscular
layers.
• Blood in the veins is dark red in
color because it contains very
little oxygen.

26. Capillaries:
• These are microscopic vessels where
exchange of various substances occurs
between blood and the surrounding tissues.
• They are connected with arterioles on one
side and venules on the other side.
• Capillaries remove nutrients and oxygen
from the blood in the arteries, and distribute
throughout the body.
• Capillaries remove cellular waste, including
carbon dioxide from the blood and distribute
the waste into the blood in the veins, where
it will be later removed.
• The smallest capillaries are located in the
brain and the intestines.
• The largest capillaries are located in the skin
and the bone marrow.

28. Circulatory
Pathways:
• The blood vessels of the
body are functionally
divided into two
distinctive circuits:
1. Pulmonary circuit or
circulation
2. Systemic circuit or
circulation

29. Pulmonary Circuit
or Circulation:
 Pulmonary circulation
is system
of blood vessels that
forms a closed circuit
between the heart and
the lungs.
 Carries deoxygenated
blood away from the
right ventricle of
the heart, to the lungs,
and returns oxygenated
blood to the left atrium
and ventricle of the
heart.

30. Systemic Circuit or
Circulation:
• Systemic circulation is a circuit which
provides the blood supply for the
tissue cells of the body and also
returns deoxygenated blood from the
tissues of the body
• Systemic circulation carries
oxygenated blood from the left
ventricle, through the arteries, to the
capillaries in the tissues of the body.
From the tissue capillaries, the
deoxygenated blood returns through
a system of veins to the right atrium
of the heart.

31. Pulmonary Circuit
• The right atrium receives deoxygenated
blood from all parts of the body through
two large veins called superior and inferior
vena cava (also known as posterior and
anterior vena cava).
• This deoxygenated blood passes into the
right ventricle.
• Upon contraction forces the deoxygenated
blood into the pulmonary arteries
• Each pulmonary artery supplies
deoxygenated blood to the lungs.
• While passing through the lungs, the blood
gives up its carbon dioxide and absorbs
oxygen.
• The oxygenated blood comes back to the
left atrium through pulmonary veins from
lungs.

32. Systemic Circuit
• The oxygenated blood which comes into the
left atrium is pushed into the left ventricle.
• Upon contraction the left ventricle forces
this oxygenated blood into the largest artery
of our body called aorta.
• The deoxygenated blood is collected from
all the organs by set of veins.
• All the veins fuse together to form the
inferior and superior vena cava.
• Both inferior and superior vena cava
discharge all the deoxygenated blood into
the right atrium.
• The blood goes to the right ventricle from
where it is pumped to lungs through
pulmonary circuit for oxygenation.

34. Difference between Pulmonary Circuit and Systemic Circuit
Pulmonary Circuit Systemic Circuit
 It carries deoxygenated blood from
the heart to the lungs
 It carries oxygenated blood from the
heart to the rest of the body
 It carries oxygenated blood from the
lungs to the heart
 It carries deoxygenated blood from
the body to the heart
 Composed of pulmonary artery and
vein
 Composed of aorta, inferior and
superior vena cava
 Carries blood to the lungs  Carries blood throughout the body

35. Review:
• Cardiovascular system through which transportation of blood in the
body takes place is known as circulatory system.
• There are two types of Circulatory system, open circulatory system and
closed circulatory system
• Open circulatory system is in which the blood does not flow inside the
blood vessels, inside it remains filled in the open tissue spaces
called sinuses e.g. snails and butterfly .
• Closed circulatory system is in which blood flows inside the closed
tubular blood vessels and does not come in direct contact with the tissues
e.g. earthworm and frog etc.
• Blood is a special kind of tissue which composed of platelets, plasma
corpuscles(R.B.Cs and W.B.C.s) that circulates in fluid form in the body
carries oxygen and nutrients.

36. Review:
• The human heart is an organ that pumps blood throughout the body
via the circulatory system, supplying oxygen and nutrients to the
tissues and removing carbon dioxide and other wastes
• Blood vessels(arteries, veins and capillaries) are tube like in shape
through which blood travels from heart to different organs of body.
There are two types of circulatory pathways, namely, Pulmonary Circuit
and Systemic Circuit.
• Pulmonary circuit carries deoxygenated blood from the heart to
the lungs, and returns oxygenated blood to the heart.
• Systemic circuit carries the blood supply to the body and returns
deoxygenated blood from body to the heart.