Create a presentation addressing all of the following topics:
Describe the mechanisms that confine cells and tissues to a specific anatomic site
Discuss four types of cellular adaptations
Compare and contrast necrosis and apoptosis
This PowerPoint® (Microsoft Office) or Impress® (Open Office) presentation should be a minimum of 15 slides (maximum of 20 slides), including a title, introduction, conclusion and reference slide, with detailed speaker notes and recorded audio comments for all content slides. Use the audio recording feature with the presentation software. Use at least four (4) scholarly sources and make certain to review the module’s rubric before starting your presentation.
Date of Submission
All human cells are eukaryotic, i.e., complex organisms with a nucleus encased within a nuclear membrane. Eukaryotic cells can sustain various environments, which allow them to carry out various metabolic operations. The cells characteristically contain several features, such as mitochondria, which are tasked with creating energy and locomotory organs, i.e., the flagella and cilia. The cells divide in a process known as mitosis, in which cells duplicate into two identical daughter cells. The process is essential as it enables new cell growth replacing worn-out cells, and is a process necessary for asexual production (Sargsyan, 2020). The cells also entail single linear DNA essential for transmitting genetic data. In this presentation., I will discuss the mechanisms that confine cells and tissues to a specific anatomic site, i.e., the extracellular matrix, the environment in which cells and tissues are held in an organized framework and interact. I will also explore cellular adaptations, which refer to the ability of cells to respond and adapt to various environmental stimuli and changes to be functional. Finally, a comparison of necrosis and apoptosis is explored, which are the distinct modes of cell death in organisms.
Mechanisms that confine Cells and Tissues to a specific Anatomic Site
Cells are contained within the extracellular matrix, a layer of systemic macromolecules surrounding all cells (Amboss, 2022). The matrix links cells and tissues, creating a structured framework for the cells to interact with each other. Cells must include intercellular recognition, adhesion, and memory mechanisms to confine themselves within the matrix and develop tissues.
Intercellular recognition is the mechanism where two cells are limited to the plasma membranes of different cells. A reaction for communication, collaboration, transport, defense, and development is triggered. Cell recognition is definitively described as a cell’s capacity to distinguish one type of adjacent cell from another. It occurs when complementary molecules on opposing cell surfaces interact. A receptor on one cell interacts with a ligand on the membrane of another cell. It sets off a cascade of mechanisms that determine cell responses ranging from essential adhesion to complex cellular differentiation.
Intercellular Adhesions refer to a single cell’s capacity to bind with another cell or an extracellular matrix. Cell adhesion is the essential mechanism in creating tissues, organs, and the body, as well as the performance of high-order processes in living organisms. Most mammalian cells in vitro are anchorage-dependent and bind strongly to the substrate. The binding is primarily regulated through cell surface molecules known as receptors which can be quantifiably researched and assessed to determine the aspects of intercellular adhesion strength. Adhesion molecules in cell walls and matrix are primarily two-dimensional. Even low-affinity chemical interactions can help maintain adhesion, provided enough connections occur anywhere along the field of cell contact. The number of binding proteins on a cell or matrix membrane is another element that influences adhesion.
Intracellular memory is a mechanism confining cells and tissues through a sustained cellular response to a transient stimulus. The strength of synapses or connections between neurons, utilized to encode memories in the brain, encodes the intracellular memory (Allesandro et al., 2021). It is uncertain how self-induced environmental stressors affect cell dynamics of different sizes. Cells can modify their surroundings by depositing molecular messages or physically reshaping the extracellular matrix.
Four Types of Cellular Adaptations
The four types of cellular adaptations include Hyperplasia, Hypertrophy, Atrophy, and Metaplasia (Amboss, 2022).
Hyperplasia is the increased number of cells in organs or tissues that may appear normal with a microscope. Hyperplasia develops due to growth factors and hormone activation, which causes accelerated cell division and proliferation in stem cells. There are two types of hyperplasia, i.e., physiological and pathologic., In physiological hyperplasia, the increase in cells is influenced by a typical stressor, for example, when the bone marrow produces more red blood cells in blood loss. An abnormal stressor affects pathologic hyperplasia, for example, hyperplastic polyps in GIT, gastric lesions distinguished by hyperplastic foveolae, and varying degrees of the inflammatory stroma.
On the other hand, hypertrophy increases cell size and volume. The cellular adaptation occurs due to the increase of structural proteins and organelles. The increase in length may be due to the excess workload imposed on single cells (Kemp et al., 2008). Once a cell increases in size, it causes the organ to increase in size, resulting in consequent rises within the intracellular protein, cytosol (intracellular fluid), and other cytoplasmic components. Similar to hyperplasia, it is divided into two, i.e., typical stressors cause physiological changes/ adaptations, such as breasts during pregnancy-induced by the prolactin-stimulating hormone, which also promotes milk production., and pathologic hypertrophy, caused by abnormal stressors, for example, myocardial hypertrophy is induced by gene mutations, which cause the heart muscle to enlarge, preventing blood flow and causing it to beat quickly.
Atrophy is the decrease in cell size influenced by the loss of organelles, proteins, and the cytoplasm, which causes tissues and organs to shrink. Atrophy is primarily caused when mutations destroy genes that build up organs among numerous factors such as poor nutrition and circulation, loss of nerve supply to the target organ, and lack of sufficient exercise to stimulate cell growth. Aging is another primary consideration that influences cellular atrophy.
Metaplasia is the abnormal formation of cells that do not usually resign within a tissue or organ, which occurs mainly in epithelial tissues as an adaptive response to stress within the cells. Metaplasia is a form of tissue in which cells are replaced by those more suited to the environment due to altered stem cell differentiation and may thus occur only in labile or stable tissues. Although the specific processes causing metaplastic tissue to become dysplastic and even malignant are unknown,
Necrosis and Apoptosis
Necrosis and apoptosis are terms that describe mechanisms of cell death. The characteristic distinguishing them is that Necrosis is a pathological process enforced by external stressors such as infections, cellular trauma, and toxins, among other agents. At the same time, apoptosis is a physiological process that occurs naturally (Panawal, 2017). The distinguishable difference between the two cell death mechanisms is that apoptosis is a predefined cell suicide mechanism, i.e., cells are no longer required for metabolic processes. As such, they commit suicide by activating the intracellular death program. Necrosis, on the other hand, is accidental cell death that occurs due to environmental factors which may lead cells to be destroyed. For example, sudden blood loss due to a cut leads to the loss of numerous erythrocytes.
Other associated differences are that Necrosis occurs through inflammation of cytoplasm and mitochondria along with cell lysis, while apoptosis occurs when cytoplasm shrinks, influencing the nucleus condensation. In apoptosis, chromatin is aggregated, while in necrosis, no structural changes are identified. The apoptosis is caspase-dependent, while necrosis is caspase-independent (Panawala, 2017). The Apoptosis mechanism is a localized process., i.e., it destroys individual cells, whereas necrosis influences contiguous cell groups., In Apoptosis, they are phagocytized either through adjacent cells or phagocytes, while in necrosis, they are only influenced by phagocytes. In Apoptosis, cell death is often beneficial. However, abnormalities may lead to diseases, while necrosis cell death is always dangerous to the associated organism. Prelytic DNA Fragmentation occurs in the apoptosis process, and postlytic DNA digestion occurs within the necrosis cell mechanism. Apoptosis controls cell numbers in the body, while necrosis is involved in the inducing organisms’ immune systems and protecting the body from pathogens.
Cells are the essential component of life itself. Numerous cellular mechanisms are crucial to healthcare advancements. Cellular research is critical for understanding the origins of cancer, identifying therapy targets, and discovering biomarkers that might detect malignant traits. Understanding how cells function in healthy and pathological situations can allow us to create better vaccines, medications, and plants.
Amboss. (2022). Cellular changes and adaptive responses. Accessed from: https://www.amboss.com/us/knowledge/cellular-changes-and-adaptive-responses/
Alessandro J., Chebbah, A.B., Cellerin, V., Benichou, O., Mège, R.M., Voituriez, R. and Ladoux, B. (2021). Cell migration guided by long-lived spatial memory. Nature Communications. Retrieved from: https://www.nature.com/articles/s41467-021-24249-8
Kemp W.L., & Burns D.K., & Brown T.G.(Eds.), (2008). Chapter 1. cellular pathology Pathology: The Big Picture. McGraw Hill. https://accessmedicine.mhmedical.com/content.aspx?bookid=499§ionid=41568284
Panawala, L. (20117). Difference between Apoptosis and Necrosis. PEDIAA. Retrieved from: http://www.rnlkwc.ac.in/pdf/study-material/zoology/DifferenceBetweenApoptosisandNecrosis_DefinitionProcessFunctionComparison-1.pdf
Sargsyan, A. (2020). Essential Notes on Pathophysiology for Advanced Practice Nurses. Digital Commons @ East Tennessee State University. Retrieved from: https://dc.etsu.edu/cgi/viewcontent.cgi?article=1002&context=etsu-oer