Get Full Essay Get access to this section to get all help you need with your essay and educational issues. Get Access The adaptation of red blood cells Essay Sample Aerobic respiration provides the energy required by all living organisms to function normally, as muscle movement and certain cell reactions are reliant on energy the transport of oxygen to the cells of tissues and organs by blood vessels is vital for respiration to occur.
In adults, erythropoies is begins with Red blood cells essay pluripotent i. Differentiation and specialization of cells may be accompanied not only by the acquisition and development of specialized structures but also by the loss of internal structures or physiological properties.
The latter is the case during erythrocyte differentiation, for mature red blood cells lack nuclei, mitochondria, endoplasmic reticulum, Golgi bodies, ribosomes, and most other typical cell organelles. Development takes place in the extra-sinusoidal stroma of the bone marrow and begins with pluripotent stem cells capable of proliferating leukocytes white blood cells as well as erythrocytes.
As a result, by the proerythroblast stage, the cells are irreversibly committed to the maturation sequence leading to erythrocytes. In humans, the average life span is days. As there are 5 billion red blood cells in each cubic centimeter of blood, a few simple calculations quickly reveal that in a typical adult the differentiation and maturation of 3 million erythrocytes is completed each second!
Genetic and Molecular Basis of Erythrocyte Differentiation: In humans, there are two pairs of alleles i. The globin chain genes are distributed between two pairs of homologous chromosomes—alpha and zeta chain genes on one chromosome pair and beta, gamma, delta, and epsilon chain genes on the other pair.
The zeta, epsilon, and gamma chain genes are expressed only during embryonic and fatal development, whereas the beta and delta chain genes are expressed from mid-fetal stages through adulthood.
Certainly, the inclination to draw a parallel between phylogeny and ontogeny at the organismal and cellular levels is unavoidable. Cellular DNA includes not only structural genes but also sequences vital to DNA organization within the chromosomes and the coordination of gene expression during differentiation.
The structural genes for the globin chains belong to this class. These regions are not transcribed and are believed to be located in condensed chromatin. In the case of the red blood cell, such a gene set would be represented by: Euchromatin has the more open structure and is transcriptionally active, whereas the condensed heterochromatin is not transcribed.
A selective expression of globin mRNA genes occurs in erythroblasts, with the result that globin mRNA is produced in amounts times greater than expected on the basis of the proportion of total template DNA represented by the globin genes. Although all protein synthesis comes to a halt during reticulocyte maturation, a red cell retains a limited metabolic capacity after release from the bone marrow.
What limited metabolism is retained by the mature cell serves to sustain it during its day and mile journey through the circulatory system. Little cell growth occurs during the periods between the successive mitotic divisions of erythropoiesis.
As a result, the mature erythrocyte is among the smallest cells of the body. The natural shape of the cell is that of a biconcave disk Fig. The factors that maintain this rather unusual cell shape have fascinated scientists for more than two centuries.
However, it is now apparent that the biconcave shape is due to the modest cytoskeleton lying just beneath the plasma membrane.Satanic ritual abuse is a.k.a. SRA, Cult Related Abuse, Ritual Abuse, Ritualized Abuse, Sadistic Ritual Abuse, Organized Sadistic Abuse, etc.
Red Blood Cells Essay Sample. 1. Introduction 2. The unique properties of stem cells and the ways of reception. 3. The application of stem cells . Essay # 1. Habitat and Habits Frogs: Rana tigrina is the most widely distributed species in Northern India.
Generally frogs are found in ponds, tanks, pools, ditches, etc.
blood cell essaysBlood is composed of cells and fluid, contain many inorganic and organic molecules. Functions of blood could be falls into three categories: transport, defense and regulation, they all have different function.
Anemia Decreases the Number of Red Blood Cells Essay Words | 3 Pages. Anemia is a blood condition with decreasing number of red blood cells (RBC) or less than normal levels of hemoglobin (an essential protein that carries oxygen to your tissues and organs) in the blood.
Essay Red Blood Cell and E.g. Sickle-cell Anemia. characterized by a deficiency in red blood cells or in the concentration of hemoglobin (iron-containing portions of red blood cells).
These deficiencies are caused by either decreased production or increased destruction of red blood cells.