In this article, we get to know about structure and functions of Red Blood Cells and white blood cells.
Red blood cells may deform, elongate, attach to other cells, and communicate with immune cells. Their membrane has a variety of effects on this. The composition of the membrane has a significant impact on these functions.
Do red blood cells have a cell wall?
The cell membrane is composed of proteins and lipids. The blood cell’s deformability and stability as it travels through the circulatory system, in particular the capillary network, are provided by this structure, which is crucial for physiological cell function.
Why do red blood cells have a thin cell wall?
The flexible membrane of the biconcave discocyte RBC has a high surface-to-volume ratio, enabling the RBC to undergo substantial, reversible elastic deformation as it repeatedly passes through tiny capillaries during microcirculation.
Do blood cells have a rigid cell wall?
A red blood cell without a thick cell wall can expand and lyse when placed in a hypotonic solution (burst). Cells with such a cell wall will swell when placed in a hypotonic solution, but once the cell is turgid (stiff), the dense cell wall prevents more water to enter the cell.
Red blood cell wall composition
The lipid bilayer, which also contains many transmembrane proteins in addition to its major lipid components, is the outermost layer of the red blood cell membrane. The lipid bilayer’s inner surface is host to the transmembrane skeleton, a structural protein network, is the third layer. Proteins make up half of the membrane mass in red blood cells from most mammals and humans. The other half are lipids, namely phospholipids and cholesterol.
Ex: Membrane lipids
Similar to essentially other human cells, the red blood cell membrane is made up of a typical lipid bilayer. Cholesterol and phospholipids make up this lipid bilayer in equal parts by weight. Since it determines several physical characteristics including membrane permeability and fluidity, the lipid composition is essential.
The proteins of the membrane skeleton, which enable the red blood cell to squeeze across capillaries that are only about half its diameter (7-8 μm), and restore to its discoid form as eventually as these cells are relieved of mechanical stresses, much like a rubber object would, are responsible for the red blood cell’s deformability, flexibility, and durability.
Red blood cell wall diagram
The red blood cell membrane is made up of three layers: the external, carbohydrate-rich glycocalyx; the inside, lipid bilayer, which also includes many transmembrane proteins in addition to its major lipid components; and the outer, lipid bilayer-facing membrane skeleton, which is made up of a structural network of proteins.
Red blood cell wall function
The most prevalent form of blood cell, the red blood cell, serves as the vertebrate’s main mechanism for providing oxygen (O2) to the bodily tissues through blood flow through the circulatory system. RBCs absorb oxygen from the lungs or fish gills, push it through the body’s capillaries, and discharge it into the tissues.
Ex: Red blood cells are essential to the process of transporting CO2 for two reasons. The first reason is because they have a lot of copies of the enzyme carbonic anhydrase inside of their cell membrane in addition to hemoglobin.
Secondary functions: Red blood cells experience shear stress in narrowed blood arteries and release ATP as a result. This reaction relaxes and dilates the vessel walls, allowing for regular blood flow.
Cellular processes: Red blood cells manufacture the energy carrier ATP via glycolysis of glucose and anaerobic glycolysis on the generated pyruvate since they lack mitochondria and do not utilise any of the oxygen they transport.
Do white blood cells have a cell wall?
White blood cells (WBCs) have a remarkable potential for communication. They bind to cell and pathogen membranes, send and receive signals from other cells, find aberrant proteins in all tissue types. A wide variety of complicated receptors and channels on and in the white blood cell membrane are needed for this.
Ex: 1. Granulocytes:
White blood cells with cell-specific granules come in five different forms in the body.
Neutrophils: Neutrophils contain multilobed nuclei and a diameter of twelve to fifteen micrometres. Neutrophils only have a short lifespan of a few days and move by diapedesis.
Eosinophils: Large granules and two nucleus lobes are features of eosinophils. These are circular cells with a diameter of roughly fifteen micrometers.
Basophils: Neutrophils and basophils are of similar size and both contain double-lobed or S-shaped nuclei.
Mast cells: Only the immature form of the round or oval mast cells can be found in the blood. They occur in a variety of tissues.
Natural killer (NK) cells: Large, granular lymphocytes known as natural killer (NK) cells develop in the lymphoid organs. These have the capacity to regenerate themselves.
White blood cells known as agranulocytes are divided into two primary types because they lack cell-specific granules – lymphocytes (T cells and B cells) and monocytes. In contrast to the other types of white blood cells, lymphocytes are made in the lymphatic tissues; their precursor cells are made in the red bone marrow.
Monocytes: Classical, intermediate, and non-classical monocytes are the three primary types of monocytes that are distinguished by specific cell membrane protein markers. Dendritic cells or macrophages can develop from monocytes.
In the above article, we studied about cell wall structure and characteristics of red blood cells, different types of white blood cells