Human Anatomy and Physiology

1. BLOOD VESSELS
 Blood vessels:
Types, Structure and position
 Dr.P.Thirunagalinga Pandiyan
M.Sc., (N) Ph.D.,(N)
College of Nursing
Madurai Medical College, Madurai.
India.

2. Blood Vessels
The networks of hollow tubes like pipes,
which carry blood to and from all parts
of the body, are called blood vessels.
These vessels carry blood in both the
directions, i.e. one from the heart to all
other parts and another from all body
parts to the heart.

3. TYPES OF BLOOD
VESSELS

5. TYPES OF BLOOD
VESSELS
 Five types of blood vessels are:
1. Arteries:
 Arteries are the main blood vessels that carry and
transport oxygenated blood or oxygen-rich blood from
the heart to other parts of the body.
 They are the strongest blood vessels with thicker walls
and are muscular in nature.
 It consists of three distinct layers, which are rigid,
thicker and highly muscular.
 Arteries are located deep within the body and are red in
colour.
 These blood vessels are with high pressure and move
in a downward direction from the heart to the body
tissues.

6. TYPES OF BLOOD
VESSELS
2.Arterioles:
 Smaller blood vessels called arterioles
branch off from arteries.
 Arterioles and arteries are both
extremely flexible.
 To maintain the blood pressure in the
body, they enlarge or contract.

7. TYPES OF BLOOD
VESSELS
3.Veins
 Veins are thin, tube-like elastic blood
vessels, present closer to the surface of
the skin.
 These translucent blood vessels are blue
in colour and carry impure or
deoxygenated blood from all parts of the
body to heart.
 These blood vessels are with low
pressure and move in an upward
direction, i.e. from the cells, tissues and
other organs to the heart.

8. TYPES OF BLOOD
VESSELS
 Compared to the arteries, veins are
thin-walled.
 Some veins possess valves, which
prevent backflow of blood, ensuring
that it flows towards the heart

9. TYPES OF BLOOD
VESSELS
4. Venules:
 Veins begin as little vessels called
venules and gradually get bigger as
they move closer to our hearts.
 Blood is delivered to venules by
capillaries.

10. TYPES OF BLOOD
VESSELS
5.Capillaries
 Short and tiny blood vessels, found
within the tissues are called
capillaries.
 Capillaries bring about the exchange
of substances between blood and
tissues.
 These blood vessels also function by
connecting arterial systems to the
venous system and help in exchange

11. TYPES OF BLOOD
VESSELS
 Sinusoids
 In certain places, including the liver
and bone marrow, the capillaries are
significantly wider and leakier than
normal. These capillaries are called
sinusoids

12. STRUCTURE OF BLOOD
VESSELS
Blood vessels have three layers of
tissue:
 Tunica intima:
 The inner layer surrounds the blood as
it flows through the body.
 It regulates blood pressure, prevents
blood clots and keeps toxins out of
blood.
 It keeps the blood flowing smoothly.

13. STRUCTURE OF BLOOD
VESSELS
 Tunica Media:
 The middle layer contains elastic
fibers that keep the blood flowing in
one direction.
 The media also helps vessels expand
and contract.

14. STRUCTURE OF BLOOD
VESSELS
 Tunica Adventitia:
 The outer layer contains nerves and
tiny vessels.
 It delivers oxygen and nutrients from
blood to cells and helps remove
waste.
 It also gives blood vessels their
structure and support.

16. POSITION OF BLOOD
VESSELS
 Coronary arteries: Heart.
 Carotid arteries: Brain, head, face and
neck.
 Vertebral arteries: Brain and spine.
 Iliac arteries: Pelvis.
 Femoral artery: Legs.
 Subclavian arteries: Head, neck and
arms.
 Celiac and mesenteric arteries:
Digestive system.

17. Aorta branches

18. Artery of upper extrimities

19. Abdominal branches

20. Arteries of lower limbs

21. Head and neck

23. Veins of the human body