Blood vessels
• OBJECTIVES
• Mention the blood vessels
• Describe the blood vessels
• Differentiate between the blood vessels.
• * Create a link of blood vessels showing their role in blood
circulation.
Blood vessels
• These are
• Arteries - ( aorta- artery- arterioles)
• Veins (venacava- vein- venules)
• Capillaries
a) Artery: Adaptation and function
1. Carries oxygenated blood away from
the heart to the tissues. (except the
pulmonary artery)
2. Blood flows at high pressure.
3. It has thick muscular walls
4. It has a small lumen to withstand the
high pressure of blood.
5. It has no valve except the
Aorta and the pulmonary artery.
6. The largest artery is called AORTA
Smallest arteries are called ARTERIOLES
b. Vein – Adaptation and function
1. Carries deoxygenated blood
from the tissues to the heart.
(except in the pulmonary vein)
2. Blood flows at low pressure.
3. It has Valves to prevent the
backflow of blood
4. It has thin wall with large lumen
for free flow of blood.
5. It is visible on the skin.
6. It has no pulse.
7. The large vein is called VENACAVA
Smaller veins are called VENULES
Identify the blood vessels
Adaptation and function
1. A capillary is formed between
an arteriole and a venule
2. It is one cell thick-tiny as a cell.
3. Capillaries facilitate easy
exchange of nutrients and
oxygen between the tissues
and the blood.
4. Very large surface area.
5. Small lumen.
6. Capillaries link arteries and
veins.
Connection of blood vessels
Comparing the blood vessels
49. Identify the following blood vessels
task
• 1.Mention the three blood vessels
• 2. In a tabular form, give five differences between artery and
vein.
Differences between artery and vein
Artery
Vein
1
Takes blood away from the heart
Takes blood to the heart
2
Has thicker muscular wall
Has thinner muscular wall
3
Has smaller lumen
Has larger lumen
4
Has no valves
Has valves
5
Carries blood at high pressure
Carries blood at low pressure
6
All arteries carry oxygenated except All veins carry deoxygenated blood except
pulmonary artery
pulmonary vein
HELP ACTIVITY ON BLOOD VESSELS
• 1. What is the function of valves?
• A. To prevent mixing of oxygenated and
deoxygenated blood
• B. To transport blood in one direction
• C. To prevent backflow of blood
2.What is the function of veins?
A. Transport deoxygenated blood
B. Transport oxygenated blood
C. Site for exchange of materials
3.What is the function of capillaries?
A. Transports deoxygenated blood
B. Transport oxygenated blood
C. Site for exchange of materials
4. Which blood vessel transports oxygenated
blood to the rest of the body?
• A. Pulmonary artery
• B. Aorta
• C. Hepatic artery
• D. Renal artery
5. What are present in veins but absent in
arteries?
A.smooth elastic tissues
B. muscular tissues
C. valves
6. What is the function of arteries?
A. Transport deoxygenated blood
B. Transport oxygenated blood
C. Site for exchange of materials
7. How are capillaries adapted for their
function?
A. Have partially permeable walls
B. One-cell thick endothelium
C. Presence of valves
D. Large lumen
8. What is the function of coronary artery?
A. Transports oxygenated blood from aorta to
heart muscles
B. Transports oxygenated blood from aorta to liver
C. Transports oxygenated blood from aorta to
kidneys
9. Which blood vessel transports
deoxygenated blood from the rest of the
body back to the heart?
A.Pulmonary vein
B.Hepatic vein
C. Renal vein
D.Vena cava