Blood Circulations in Human Body
✔ Blood
Blood is a red-colored fluid connective tissue that
circulates in the arteries and veins of humans and other vertebrate animals,
carrying oxygen to and carbon dioxide from the tissues of the body.
Structure of blood
⮚
It is the connective tissues that contain
plasma and cells or blood corpuscles
⮚
It supplies all the necessary materials required
for life.
⮚
Blood contains blood plasma (55%) and blood
cells (45%).
⮚
A healthy adult person has about (5.5) liter of blood.
Blood plasma
❖
Blood plasma is a yellowish substance that
contains about (90%) water and (10%) organic and inorganic substances.
Organic substances present in plasma are protein, carbohydrate fats, etc.
inorganic matters like salts.
Functions
of plasma
⮚ It
regulates the amount of water in the blood.
⮚ It
transports absorbed food materials and oxygen into various parts of the body.
⮚ It transports hormones secreted by endocrine
glands.
⮚ It
removes the wastes from the human body in the form of urine.
⮚ It
prevents blood clotting inside the blood vessels.
Blood
cells or blood corpuscles:
• Blood
cells remain floating in the blood plasma. The three types of blood cells are:
a) Erythrocytes
or RBCs.
b) Leucocytes
or WBCs.
c) Thrombocytes
or platelets.
✔ Erythrocytes of RBCs
Red blood cells (RBCs), also called erythrocytes, are cells that
circulate in the blood and carry oxygen throughout the body. A red
pigment called hemoglobin is found in the red blood cells. It also contains
iron. It absorbs oxygen from the lungs and transports' through the body in the form
of oxyhemoglobin.
The absence of red blood cells on the blood causes anemia, In such conditions, a person feels tired even after a short walk.
✔ Leucocytes or WBCs
White blood cells (WBCs), also called leukocytes or leucocytes,
are the cells of the immune system that are involved in protecting the body
against both infectious diseases. WBCs are round or irregular shaped and can
change their shape like amoeba. WBCs are colorless. The life span of WBCs is
about two weeks.
There are two
types of leucocytes :
-
Granular leucocytes .
-
Agranular leucocytes.
Granular leucocytes:It contains granules in their
cytoplasm. A type of white blood cell filled with microscopic granules (tiny
sacs) containing enzymes that digest microorganisms. ... They do not respond
exclusively to specific antigens, as do B-cells and T-cells. Neutrophils,
eosinophils, and basophils are all types of granulocytes.
✔ Eosinophils:
There are non-phagocytic. The main function of eosinophils is to destroy
toxins.
✔ Basophils:
There are fewer numbers among the leucocytes.
They release the heparin and serotonin
✔ Neutrophil: there are largest in number among all the leucocytes. They engulf germs and there are called phagocytes.
Agranular leucocytes: A leukocyte lacking
apparent cytoplasmic granules under a microscope.
❖ They are two types of Agranular leucocytes :
✔ Lymphocytes: It produces antibodies to destroy germs. They also help in healing injuries. They
are smaller in the size.
✔ Monocytes: Monocytes are larger in the size.
Thrombocytes or platelets
✔ They
are non-nucleated and oval-shaped blood cells.
✔ It
is formed from the large cells of bone marrow.
✔ The
life span of platelets is about 2 to 3 days.
✔ They
are responsible for the blood clotting at the site of injury or cut.
✔ They
are the fragments of the cells rather than true cells.
Functions of
blood
❖ Transportations
:
-
It supplies oxygen from the lung to body cells and
carbon dioxide from the cells to the lung for removal.
-
It absorbed the nutrients are transported to
the body cells and tissues.
-
It is responsible to transport food,
oxygen, and waste materials in human bodies.
-
It transports food, carbon dioxide, and
nitrogenous wastes in dissolved form.
❖ Regulations
:
-
Blood regulations the body temperature.
-
It regulates the number of fluids and various
chemicals in the tissues.
-
It regulates the body's systems and
maintains homeostasis.
-
It transports hormones and other signals
throughout the body and regulates body pH and core body temperature.
❖ Protections
§
It maintains the immunity power of the body.
§ It destroys toxic substances and diseases causing germs
Blood Vessels
• Blood
vessels: flow blood throughout the body. Arteries transport blood away
from the heart. Veins return the blood back toward the heart. Capillaries
surround body cells and tissues to deliver and absorb oxygen, nutrients, and
other substances.
• The Three Major Types of Blood Vessels: Arteries, Veins, and Capillaries.
Arteries
• The arteries are
the blood vessels that deliver oxygen-rich blood from the heart to the tissues
of the body. Each artery is a muscular tube lined by smooth tissue
and has three layers: The intima, the inner layer lined by a smooth tissue
called the endothelium.
Veins
❖ Any
of the tubes form part of the blood circulation system of the body, carrying
in most cases oxygen-depleted blood towards the heart.
❖ Carries
blood that is low in oxygen content from the body back to the heart.
Capillaries
• Any
of the fine branching blood vessels that form a network between the arterioles
and venules. Capillaries are very tiny blood vessels.
• They
help to connect your arteries and veins in addition to facilitating the
exchange of certain elements between your blood and tissues.
HEART
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. "The heart is a large muscular pump and is divided
into two halves - the right-hand side and the left-hand side. The right-hand
side of the heart is responsible for pumping deoxygenated blood to
the lungs. The left-hand side pumps oxygenated blood around the body.
Functions of the HEART:
-
To transport nutrients, gases, and waste products
around the body.
-
To protect the body from infection and
blood loss.
-
To help the body maintain a
constant body temperature ('thermoregulation')
-
To help maintain fluid balance within the body.
Four valves in the HEART
⮚ Tricuspid valves: The tricuspid valve is located
between the right auricle and the right ventricle.it has three flaps. Blood passes from the right auricle to the right ventricle through these valves. When the right ventricle
shrink, the tricuspid valve closes, and blood pass to the lungs through the pulmonary
artery.
⮚ Pulmonic valves: A semilunar valve between
the pulmonary artery and the right ventricle of the heart that
prevents the blood from flowing back into the right ventricle. The pulmonary
valve normally acts like a one-way door from your heart's right ventricle to
the lungs. Blood flows from the right ventricle through the pulmonary
valve to the pulmonary artery and then into the lungs, where it picks
up oxygen to deliver to your body.
⮚ A bicuspid aortic valve (BAV): It is an aortic valve that only has two
leaflets, instead of three. The aortic valve regulates blood flow
from the heart into the aorta. bicuspid aortic valve (BAV) is an inherited
form of heart disease in which two of the leaflets of the aortic
valve fuse during development in the womb resulting in a two-leaflet valve (bicuspid
valve) instead of the normal three leaflet valve (tricuspid)
⮚ Aortic valves: Aortic valve is located
between the left ventricle and the aorta (the large blood vessel that
carries blood to the rest of the body). When your ventricle contracts, blood is
forced through the aortic valve, into the aorta, and out to the rest
of your body.
Blood circulations
-
The circulatory system is made up of blood vessels
that carry blood away from and towards the heart. Arteries carry blood away
from the heart and veins carry blood back to the heart. The
circulatory system carries oxygen, nutrients, and hormones to cells, and
removes waste products, like carbon dioxide. - Systemic circulation provides the functional blood supply to all body tissue. It carries oxygen and nutrients to the cells and picks up carbon dioxide and waste products. Systemic circulation carries oxygenated blood from the left ventricle, through the arteries, to the capillaries in the tissues of the body.
Heartbeat
- The rhythmic contractions and relaxations of the heart are called heartbeat. A normal resting heart rate for adults ranges from 60 to 100 beats per minute. Generally, a lower heart rate at rest implies more efficient heart function and better cardiovascular fitness. For example, a well-trained athlete might have a normal resting heart rate closer to 40 beats per minute.
Blood Pressure
High blood circulations
• High
blood pressure (HBP or hypertension) is when your blood pressure,
the force of your blood pushing against the walls of your blood vessels,
is consistently too high. Most people who have high blood pressure do
not have symptoms. In some cases, people with high blood
pressure may have a pounding feeling in their head or
chest, a feeling of lightheadedness or dizziness, or other signs.
Some causes of high blood pressure
i.
A diet full of oily products.
ii.
Tobacco smoking.
iii.
Mental tension.
iv.
Kidney disorder.
v.
Lack of physical exercise.
vi.
Salty food.
vii.
Alcohol
viii.
Age above 40 years
ix.
Adrenal and thyroid disorder
x.
Genetic
reasons
Some symptoms of high blood pressure
1) Headache.
2) Dizziness.
3) Blurred
vision.
4) Chest
pain.
5) Short
breathes.
Some preventive measures for High blood pressure
-
Eating a healthy
diet. To help manage your blood pressure, you should limit
the amount of sodium (salt) that
you eat, and increase the amount of potassium in your diet. It is also
important to eat foods that are lower in fat, as well as plenty of fruits,
vegetables, and whole grains. The DASH eating plan is an example of an
eating plan that can help you to lower your blood pressure.
-
Getting regular
exercise. Exercise can help you maintain a healthy weight and
lower your blood pressure. You should try to get moderate-intensity aerobic
exercise at least 2 and a half hours per week, or vigorous-intensity
aerobic exercise for 1 hour and 15 minutes per week. Aerobic exercise, such as
brisk walking, is an exercise in which your heart beats harder and you use
more oxygen than usual.
Diabetes
• A
disease in which the body's ability to produce or respond to the hormone
insulin is impaired, resulting in abnormal metabolism of carbohydrates and
elevated levels of glucose in the blood.
CAUSES OF DIABETES
§
Genetic reason.
§
Insufficient insulin production
§
Stressful lifestyle etc.
• Intense
thirst
• Increased
appetite
• Dizziness
• Vision disorder
Preventives measures diabetes
1. Check
your risk of diabetes. Take the Life! ...
2. Manage
your weight. ...
3. Exercise
regularly. ...
4. Eat
a balanced, healthy diet. ...
5. Limit
takeaway and processed foods. ...
6. Limit
your alcohol intake. ...
7. Quit
smoking. ...
8. Control
your blood pressure.
Uric Acid
• Uric
acid is a chemical created when the body breaks down substances called
purines. Purines are normally produced in the body and are also found in some
foods and drinks. Foods with high content of purines include liver, anchovies,
mackerel, dried beans and peas, and beer.
CAUSES OF Uric
Acid
⮚ Most
of the time, a high uric acid level occurs when your kidneys don't
eliminate uric acid efficiently. Things that may cause this
slow-down in the removal of uric acid include rich foods, being
overweight, having diabetes, taking certain diuretics (sometimes called water
pills), and drinking too much alcohol.
Symptoms of Uric Acid
• severe pain in
your joints.
• joint
stiffness.
• difficulty
moving affected joints.
• redness and swelling.
• misshapen joints.
Preventives measure Uric Acid
• Purine-rich
foods include some types of meat, seafood, and vegetables. All of these foods
give off uric acid when they're digested. Avoid or reduce your intake
of foods such as organ meats. Avoid foods containing high purine such as red
meat, offal, oily fish, seafood, and foods containing yeast extract.
• Avoid
sugary drinks such as soft drinks.
• Maintain a healthy weight
