Difference Between Plasma And Platelets

What is Plasma in Blood?

Plasma is the fluid portion of the blood and makes up approximately 55% of the total volume. This pale yellow fluid is the medium in which many substances are transported throughout the body.

Composition of Plasma

• Water: Plasma is primarily composed of water, about 90-92%, that acts as the solvent for various solutes.

• Proteins: Plasma contains albumin, involved in the maintenance of osmotic pressure, globulins, involved in immune responses, and fibrinogen, which is necessary for blood clotting.

• Electrolytes: Plasma contains important electrolytes such as sodium, potassium, calcium, and bicarbonate, the major factors in the maintenance of fluid balance and nerve conductance.

• Nutrients: Plasma carries nutrients, mainly glucose, amino acids, and lipids, to cells for energy and growth.

• Waste Products: Plasma carries metabolic waste products, for example, urea and creatinine, to the kidneys for excretion.

Functions of Plasma

• Transport: Plasma serves as a medium of transport for nutrients, hormones, gases, and waste products, enabling their circulation across the body.

• Regulation: Plasma participates in the regulation of body temperature, pH levels, and osmotic pressure and thus contributes to the preservation of homeostasis.

• Immune function: Plasma proteins including antibodies are involved in the immune response to protect the host from infection.

What are Platelets?

Platelets are small, disc-shaped fragments of cells that are involved in blood coagulation and hemostasis. They are important in preventing loss of blood when the vessels are injured.

Composition of Platelets

• Cell Fragments: Platelets are fragments of cells, and not cells themselves. The megakaryocytes are gigantic cells that reside in the bone marrow.

• Granules: Platelets possess granules that pack different products of these cells, for example, clotting factors and growth factors, which are crucial for their functioning.

Functions of Platelets

• Hemostasis: The most important function of platelets is to prevent haemorrhage by acting as a plug that forms at the site of injury in the vasculature.

• Blood Clotting: Chemicals released by platelets promote the cascade of coagulation, ultimately leading to a stable blood clot.

• Wound Healing: Growth factors released from platelets are responsible for tissue repair and regeneration following injury.

Key Differences Between Plasma And Platelets

Role of Plasma and Platelets In Health

Both plasma and platelets are integral parts of the maintenance of health.

• Nutrient and waste products are transported by plasma helps in cellular functioning

• While platelets prevent excessive bleeding and facilitate clotting to start the healing process of wounds.

• Disorders of either component lead to serious health complications.

Plasma vs Platelets NEET MCQs (With Answers & Explanations)

Important topics for NEET exam are:

• Components of Plasma

• Components of Platelets

• Major differences

• Disorders related to plasma and blood

Practice Questions for NEET

Q1. The life span of thrombocytes is

1. 3 to 4 weeks

2. 4 to 5 weeks.

3. 3 to 7 days

4. None of the above

Correct answer: 3) 3 to 7 Days

Explanation:

They are non-nucleated round, biconvex cells. They originate from megakaryocytes by cytoplasmic extension. They release clotting factor (thromboplastin) for blood coagulation at the site of injury. Platelets play a crucial role in wound healing by forming a platelet plug, which helps seal blood vessels and stop bleeding. They also release other substances that help in the constriction of blood vessels and the promotion of tissue repair. Platelet count and activity are essential for maintaining proper clotting and preventing excessive bleeding.

Hence, the correct answer is option 3) 3 to 7 days.

Q2. How serum is different from plasma in having

1. Excess of fibrinogen and other clotting factors

2. Absence of fibrinogen and other clotting factors

3. Absence of haemoglobin

4. Excess of haemoglobin

Correct answer: 2) Absence of fibrinogen and other clotting factors

Explanation:

The serum is similar to plasma in terms of its composition, but it does not contain clotting factors or fibrinogen, which are removed during the process of blood clotting. Serum contains a variety of important proteins, electrolytes, hormones, enzymes, and other substances that are important for various physiological functions in the body.

Plasma constitutes 55% of the total blood present in the human body.

The explanation for the Incorrect option:

Haemoglobin is a protein found in red blood cells that binds with oxygen to transport it from the lungs to the body's tissues. It is essential for oxygen delivery to cells and tissues throughout the body.

Hence, the correct answer is option 2) Absence of fibrinogen and other clotting factors.

Q3. A decrease in platelets count is termed as

1. Leucocytopenia

2. Thrombocytopenia

3. Leukemia

4. Thrombocytic

Correct answer: 2) Thromobocytopenia

Explanation:

Thrombocytopenia is a condition where there's a decrease in the platelet count. This can lead to what are known as bleeding disorders like purpura. The normal life of a platelet is typically 5 to 9 days. When platelet count goes below 150,000 per microliter of blood, individuals might experience increased bruising and prolonged bleeding due to the impaired ability of blood to clot, which requires medical evaluation and possible treatment.

Hence, the correct answer is Option 2) Thrombocytopenia.

Also Read:

• MCQs on Blood Plasma

• Components of Blood

• Morphology and Anatomy of Cockroach