Composition and functions of blood
Blood
is a vital fluid in the human body that performs various functions essential
for maintaining health and homeostasis. It is composed of different cellular
and non-cellular components. Let's take a look at the composition and functions
of blood:
Composition
of Blood:
1.
Plasma:
Plasma is the liquid component of blood, making up about 55% of its total
volume. It is a yellowish, straw-colored fluid containing water, electrolytes
(such as sodium, potassium, calcium, and chloride), proteins (albumin, globulins,
fibrinogen, etc.), hormones, waste products, and nutrients.
2.
Formed
Elements: The formed elements of blood include:
a.
Red
Blood Cells (Erythrocytes): These are the most abundant cells
in blood, responsible for carrying oxygen from the lungs to tissues and
removing carbon dioxide from the tissues to the lungs. Red blood cells contain
hemoglobin, a protein that binds and transports oxygen.
b.
White
Blood Cells (Leukocytes): There are several types of white blood
cells, each with specific functions related to the immune response. They defend
the body against infections, foreign invaders, and abnormal cells.
c.
Platelets
(Thrombocytes): Platelets are tiny cell fragments that
play a crucial role in blood clotting (hemostasis). When there is an injury to
a blood vessel, platelets aggregate to form a plug, stopping the bleeding.
Functions
of Blood:
1.
Oxygen Transport: Red
blood cells carry oxygen from the lungs to all the tissues and organs
throughout the body. Hemoglobin within red blood cells binds to oxygen in the
lungs and releases it in the capillaries, where it diffuses into the cells.
2.
Carbon
Dioxide Transport: As tissues use oxygen, they produce
carbon dioxide as a waste product. Red blood cells also help transport carbon
dioxide from tissues to the lungs, where it is exhaled from the body.
3.
Immune
Response: White blood cells are essential components of the
immune system, defending the body against infections and foreign invaders such
as bacteria, viruses, and other pathogens.
4.
Blood
Clotting: Platelets play a crucial role in forming blood
clots to stop bleeding from damaged blood vessels. This process, known as
hemostasis, prevents excessive blood loss in case of injury.
5.
Regulation
of Body Temperature: Blood helps regulate body temperature
by distributing heat throughout the body. It carries heat from the core to the
skin's surface, promoting heat loss through sweating and radiation.
6.
Transport
of Nutrients and Hormones: Blood transports various
nutrients, such as glucose, amino acids, and fatty acids, from the digestive
system to cells. It also carries hormones produced by endocrine glands to their
target tissues, regulating various physiological processes.
7.
pH
Balance and Electrolyte Balance: Blood helps maintain
the body's acid-base balance (pH) and regulates the concentrations of
electrolytes like sodium, potassium, calcium, and chloride to ensure proper
cellular function.
Overall, the composition and functions of blood are
crucial for the survival and normal functioning of the human body. Any
imbalances or disorders affecting blood can lead to severe health issues and
complications.
