The Human Blood Circulatory system Humans and other vertebrates have a closed blood circulatory system: This system consists of the heart (pump), series of blood vessels the blood that flows through them. This means that circulating blood is pumped through a system of vessels. Functions of Human Blood Circulatory System 1. oxygen 2. carbon dioxide 3 nutrients 4. water 5. ions 6. hormones 7. antibodies 8. metabolic wastes

1. The Human Blood
Circulatory system
By: BLUE BIRD

2. In the name of Allah, the Most-
Merciful, the All-Compassionate
Bismillah Walhamdulillah Was Salaatu
Was Salaam 'ala Rasulillah
As-Salaam Alaykum Wa-Rahmatullahi
Wa-Barakaatuh
"May the Peace and Blessings of Allah
be UponYou“

3. Blood Circulatory system
Humans and other vertebrates have a
closed blood circulatory system:
• This system consists of
» the heart (pump),
» series of blood vessels
» the blood that flows through
them.
• This means that circulating blood is
pumped through a system of vessels.

4. Functions of Human Blood
Circulatory System
 1. oxygen
 2. carbon dioxide
 3 nutrients
 4. water
 5. ions
 6. hormones
 7. antibodies
 8. metabolic wastes
Includes transport of following

5. The Human Blood
Circulatory System
 4 chambered heart
 Arteries
 Capillaries
 Veins

6. The Human Blood
Circulatory System

7. Heart
• The Heart Located near the center of
the chest Hollow structure
• The Heart Enclosed in a protective
sac called the p e r i c a r d i u m
• The heart contracts about 72 times
per minute
Pumps about 70ml of blood with
each contraction.

8. The Heart

9. Structure
• Layers:
 Epicardium
 Myocardium(Contractions of the
myocardium pump blood through the
circulatory system)
 endocardium
The Heart

10. • Chambers:
Two atria (right and left)
Two ventricles (right and left)
• The right and left sides of the heart are
separated by a septum, or wall. The septum
prevents the mixing of oxygen rich and
oxygen poor blood.
• The upper chamber (receives blood) is the
atrium. The lower chamber (pumps blood
out of heart) is the ventricle
The Heart

11. Valves
 Two atrioventricular valves:
 tricuspid and bicuspid (mitral)
 Two semilunar valves:
pulmonary and aortic
• Flaps of connective tissue, called valves, are
located between the atria and ventricles.
• Blood moving keeps the valves open. When
the ventricles contract, the valves close which
prevent blood from flowing back into the atria.
• Each atrium and ventricle contracts as a unit.

12. Arteries
• muscular vessels carrying
blood away from heart
• carry oxygenated blood
– Exception- pulmonary artery
(to lungs)
• Thick walls-need to withstand
pressure produced when heart
pushes blood into them

13. Capillaries
• thin walled (one cell layer) vessels
• arise from arterioles (tiny arteries)
• form capillary beds
• all exchange between blood &
cells occurs here(Important for
bringing nutrients and oxygen to
tissues and absorbing CO2 and
other waste products)

14. Capillaries
• composed of interlocking cells
• one cell thick
• nutrients, ions, water, & oxygen diffuse here
• Blood moves from capillary to a venule, picks up:
• ions
• water
• carbon dioxide
• metabolic wastes
• nutrients from intestine
Materials leave capillaries by three
mechanisms:
1. Diffusion
2. Hydrostatic pressure
3. Pinocytosis

15. Arterioles and Capillaries

16. Capillary Structure

17. Veins
• Venules (branch of veins) receive blood
from the capillaries
• Low oxygenated blood transferred to veins
• Veins carry low O2 blood to heart
– Exception- pulmonary vein carries oxygenated blood
• Thin walled & flattened
• Nearer to body surface than arteries
• Blood pressure is much lower than in
arteries

18. Movement through veins
assisted by:
1) one way flap-like valves allow blood
to move in one direction (toward
heart)
2) some smooth muscle around larger
veins that contracts and moves blood
3) limb and breathing movements
literally massages veins and
squeezes blood along

19. Circulation Through Human
Heart
Blood enters
the RIGHT
SIDE of heart
Right
atrium
Right
ventricle
Pulmonary
artery
Alveoli
in
lungs
Oxygenate
d blood
Pulmonary
Veins
Left
Atrium
Left
Ventricle
Blood leaves
through
Aorta
Flows
to body

21. Control of the Heart
1. Extrinsic (outside)
2. Intrinsic (within)

22. Extrinsic (outside)
control of heart beat
• autonomic nervous system
• adrenal hormone epinephrine
• heart itself can secrete
regulatory hormones when
changes in blood pressure in
the atria are detected.

23. Intrinsic (within) control
• Origin of heart beat
– Sinoatrial (SA) node
(pacemaker)
• May be influenced by
autonomic nervous system

24. Human Blood
Circulatory System
Circuits
1.Hepatic Portal Circuit
2.Renal Circuit
3.Cardiac Circuit
4.Systemic Circuit

25. Pulmonary Circuit:
Oxygenation of Blood
– Deoxygenated blood through the vena
cava to the right atrium
– Deoxygenated blood through the right
atrioventricular valve to the right ventricle
– Deoxygenated blood through the
pulmonary semilunar valve to the
pulmonary trunk and the lungs
– Oxygenated blood through the pulmonary
veins to the left atrium
– Oxygenated blood through the left
atrioventricular valve to the left ventricle

26. Systemic Circuit: Delivery of
Oxygenated Blood to Tissues and Return
of Blood to the Heart
– Oxygenated blood through the aortic
semilunar valve to the aorta
– Oxygenated blood through branching
arteries and arterioles to the tissues
– Oxygenated blood through the arterioles to
capillaries
– Deoxygenated blood from capillaries into
venules and veins
– Ultimately to the vena cava and into the
right atrium

27. Cardiac Cycle

28. Heart Sounds and
Heart Valves
• Lub-dub
• Heart murmurs

29. Cardiac Conduction System
Coordinates Contraction
• SA node: cardiac
pacemaker
• AV node: relay
impulse
• AV bundle and
Purkinje fibers:
carry impulse to
ventricles

30. Electrocardiograms (EKG/ECG)
• Three formations
– P wave: impulse across atria
– QRS complex: spread of impulse
down septum, around ventricles
in Purkinje fibers
– T wave: end of electrical activity
in ventricles
• Arrythmias, ventricular
fibrillation (due to any change)

31. Electrocardiograms
(EKG/ECG) (cont.)

32. Blood Pressure
• Definitions: “normal”
– Systolic pressure
– Diastolic pressure
• ideal blood pressure is considered to be
120/80mmHg.
• The force of blood on the wall of the
arteries is known as blood pressure
• Measurement:
sphygmomanometer

33. Blood Pressure
• Hypertension: high blood pressure
• 140/90mmHg or higher
– The silent killer
– Various risk factors
• Hypotension: low blood pressure
• 90/60mmHg or lower
• Clinical signs: dizziness, fainting
– Causes: orthostatic, severe burns,
blood loss

34. Regulation of the Cardiovascular
System: Baroreceptors
• Baroreceptors: pressure receptors in aorta
and carotid arteries
• Steps in mechanism
Blood pressure rises, vessels
stretched
Signals sent to brain in the
cardiovascular center
Heart signaled to lower heart
rate and force of contraction
Arterioles vasodilate,
increasing blood flow to tissues
Combined effect lowers blood
pressure

35. Regulation of the Cardiovascular
System: Nervous and Endocrine Factors
• Medulla oblongata signals
– Sympathetic nerves: constrict
blood vessels, raising blood
pressure
– Parasympathetic nerves: dilate
blood vessels, lowering blood
pressure
• Hormones: epinephrine (adrenaline)
• Local requirements dictate local
blood flow

36. Cardiovascular Disorders
• Angina pectoris: severe chest pain
(a warning)
• Myocardial infarction/heart attack:
permanent cardiac damage
• Congestive heart failure: decrease
in pumping efficiency
• Embolism: blockage of blood
vessels
• Stroke: impaired blood flow to the
brain

37. Reducing the Risk of
Cardiovascular Disease
• Smoking: cigarette smoke contain
upto 50% hydrocarbons that are
hazardous.
• Blood lipids: monitor cholesterol
levels
• Exercise: regular and moderate
• Blood pressure: treat hypertension

38. Weight:
being overweight increases risk of
heart attack and stroke
Control of Diabetes Mellitus:
early diagnosis and treatment delays
onset of related problems
Stress: avoid chronic stress

39. Blood
• It is a type Connective tissue
• It contains plasma matrix + 3 types cells
Plasma = 90% water + 10% plasma
solids.
Solids include:
 Urea
 amino acid
 Glucose
 Hormones
 Ions
 Fats
 proteins

40. The 3 Major Blood
Proteins
Albumins - large proteins that bind
impurities & some toxins, aid in transport
of hormones, fatty acids and ions, help
maintain osmotic balance.
GLOBULINS - include antibodies
(immunoglobins IgA,IgE,IgD,IgG,IgM)
- transport substances such as fatty acids,
hormones and vitamins
FIBRINOGEN - role in blood clotting

41. Blood Cells
A) Erythrocytes
B) Leukocytes
C) Platelets

42. Erythrocytes
(red blood cells)
1. small, disk-like shape
2. no nucleus
3. cannot reproduce
4. Lasts 4 months then rupture
5. produced by red bone marrow
6. contain hemoglobin(give red color)
7. carry oxygen

43. Leukocytes
(white blood cells)
• Nucleus present
• Active in immune system
• most are neutrophils that engulf
microorganisms
• Basophils
• Eosinophils
• Lymphocytes
• Monocytes (macrophages)

44. Platelets
(thrombocytes)
• tiny
• Numerous in number
• cell fragments
• aid blood clotting