Question

The major proteins of blood plasma are:
A. Albumin, globulin and fibrinogen
B. Collagen, elastin and fibrinogen
C. Albumin, glutelin and p-protein
D. Actin, myosin and tubulin

Answer 1

Blood plasma is the liquid portion of the blood that consists of water, ions, enzymes and proteins. Out of which, 90% is water and 10% is made up of ions, proteins, dissolved gases, nutrient molecules and wastes.

Complete step by step answer: Albumin is a globular protein and in general, they are transporter proteins that are attached to the ligand. Human serum albumin is present in the blood plasma that allows the transport of many molecules. Globulins are globular proteins made in the liver, whereas other globulins are made by the immune system. Alpha 1 globulin, alpha 2 globulin, beta globulin and gamma globulin are the types of globulin proteins. Fibrin is a non-globular protein that is involved in the blood clotting process. All these three proteins are present in blood plasma. Fibrinogen is the inactive form of the fibrin. It is activated only during the blood coagulation process. Calcium ions play an important role in the activation process.
i. Collagen is the structural protein found in the extracellular matrix of connective tissues. It is mainly found in the skin, bone, cartilage, ligaments and tendons.
ii. Elastin is also present in the extracellular matrix of the connective tissue and is highly elastic in nature, such that it allows the tissue to resume its shape.
iii. Glutelin is a prolamin protein mainly found in the endosperm of the seeds of certain plants, whereas p-proteins are found in the sieve tubes of the phloem tissue in plants.
iv. Actin and myosin are present in the cell nucleus and cytoplasm. It is a motor protein associated with the movement of the molecules. Tubulin or microtubule are mainly found in the centrosome and spindle cell bodies.
Hence, the correct answer is option A.

Note: Serum albumin maintains the oncotic pressure, whereas ovalbumin is a storage protein. Gamma globulins are immunoglobulins also called the antibodies. It protects the body from pathogens, and fibrin is the activated form of the fibrinogen.