Essays on Cell Membrane

Gene replacement refers to a technique which utilizes homologous recombination (Carter & Shieh, 2010, p. 265), to make alterations by either adding a gene, deleting a gene or including point mutations. Gene replacement attempts to cure most of the genetic diseases at molecular level. A successful gene replacement prevents a protein from causing harm, giving new functions to proteins, and recovering or enhancing the normal function of a protein. This technique is commonly used to prevent, treat or improve animals. This is a permanent process that is very beneficial to animals. The process of animal gene replacement involves several processes ...

People working in manufacturing and chemical industries are more prone to health hazards as they are exposed to dangerous substances that have adverse health effects on them. Frequent exposure to synthetic substances causes nausea, vomiting, and headaches, which, if not treated at earlier stages turn into life threatening diseases. These substances directly or indirectly exert toxic elements through biological, chemical, physical, genetic or psychological agents on living organisms and other biological systems, and this study is known as toxicology. In an organism these toxic elements are absorbed systematically through the skin, lungs, or gastro-intestinal tracts. The effect of these ...

Cholesterol is a fat that is needed to build cells, certain hormones and bile acids. Cholesterol synthesis is determined genetically, without it the body cannot fully function, but an excess can have the opposite, negative effect. After the growth of the organism is finished and the cells do not divide so rapidly, cholesterol continues to be synthesized by the liver in the same size. Moreover, a large part of the cholesterol is synthesized in the liver, while smaller part comes with the food. Fats in general and cholesterol in particular will not dissolve in blood, so to transport them ...

A neuron is a specialized type of cell that helps in impulse conduction in the body. It is a basic unit of communication in the body. It receives and initiates the information reception and transmission to all parts of the body. The structure of the neuron is made of several parts that include dendrites, Soma (cell body), nucleus, cell membrane, axon, myelin sheath, a node of Ranvier and terminal Buttons or axon terminal (Marieb, 2004). The figure below shows the structure of the neuron. Figure 1: structure of neuron (Shonkoff & Phillips, 2010). For neural impulse to occur, the stimulus ...

{Author Name [first-name middle-name-initials last-name]} {Institution Affiliation [name of Author’s institute]} A cell is a form of the miniature factory that encloses a distinct chemical system that is involved in structural maintenance, homeostasis, energy generation and reproduction. Every organism is made of these structural living units. The cell divides and produces more cells and assists in the growth of the organism. There are two types of cells, eukaryotic and prokaryotic. Eukaryotic cells are characterised by a membrane-bound nucleus enclosing the genetic material. The Eukaryotic cells can be divided into three main parts, plasma membrane, cytoplasm, and nucleus (Cooper & ...

Introduction

Osmosis is the process by which water molecules move from a region of low concentration of solute to a region of high concentration of solute through a semipermeable membrane (Van 3). Osmosis therefore can define the movement of water in and out of the cytoplasm of a cell. A solution with a higher concentration of solute molecules than that of the cell cytoplasm is said to be hypertonic to the cell. On the other hand, a solution with a lower concentration of solute than that of the cell cytoplasm is said to be hypotonic to the cell. Purpose: The ...

Abstract

The prodrug design is an efficient and powerful method that can be practised in a wide range of parent drug compounds, administration routes and preparations. Its main goal is to overcome the drawbacks of regular drug compounds by effectively targeting the drug's particular site of action for improved therapy. This assignment seeks mainly to depict the different classifications of prodrugs and the role these play in drug design through the use of several examples. A brief description highlighting the modern aspects of prodrug design is also covered here.

Introduction:

Prodrugs are inactive forms of drug compounds that undergo chemical or ...

Abstract. In recent time, connectomics which is filed aimed to construct wiring diagram of the brain at the level of synapses and their connections has gained an increasing interest and is very promising for neuroscience. Advance in technology allow to acquire huge volumes of data and the challenge for researchers and scientist now is storage, visualization, and processing of the data. Developing GPU technology provides effective solutions for computing on large datasets and its visualization. Moreover, several recent work propose techniques for optimized segmentation, reconstruction, proofreading, and visualization of connectome. However, existing solutions are still not efficient enough and ...

Yeast, Epithelial and Dental plaque

Compare your observations from the four activities of fresh wet mount, direct staining using crystal violet, and indirect staining using both Congo Red and crystal violet. Wet mount of S. cerevisiae under magnification of X10 and X40, revealed the cells as being independent, with oval shapes. All the cells in wet mount, had same shape appearance, with borders that could not be clearly distinct. However, in wet mount, it was not easy to determine epithelial cells shape. In the direct staining, cells shapes could be determined since cells had a violet color. This made the cells to be visible ...

Introduction

The cell membrane encloses the cell contents and regulates what gets in and out of the cell. This property of a cell is referred to as selective permeability and helps in maintaining life processes (Beckett 22). The property enables physiological process such as diffusion and osmosis to proceed. Diffusion is the movement of particles from a region of high concentration to a region of low concentration (Roberts and Mitchelmore 38). In a cell membrane, the molecules will diffuse from the side where the molecules are more to a region where they are less. Because of selective permeability, only molecules ...

General features of melatonin

Melatonin is a hormone, which is thought to play an important role in daily processes of humans’ lives, being secreted by the pineal gland, which is an endocrine gland, located in the middle of the brain. After its discovery the first function (which later gave the name to this hormone) was the ability of this hormone to lighten one’s skin color. This experiment was conducted on frogs, however even nowadays everybody knows that our sunbathing results in suntan due to activity of melatonin. This is a so-called skin-darkening effect of melatonin. First discoveries of this hormone were done ...

Discuss the therapeutic effects of Ultrasound in the treatment of a tennis elbow soft tissue injury

Introduction The ultrasound is used as a treatment for soft tissue injuries using sound waves that are beyond the range of normal hearing. An ultrasound consists of inaudible high frequency mechanical vibrations (Gibbs, Cole and Sassano, 2009) which are created upon the conversion of electrical energy into acoustic energy through mechanical deformation of the piezoelectric crystal which lies within the transducer (Rheumatology, 2011). Therapeutic ultrasound uses a frequency between 0.75 and 3 MHz (Knight, Knight and Draper, 2013) for heating deeper and superficial tissues. Low frequency ultrasound at 1 Mhz is absorbed by tissues up to 3 to 5 cm ...

DISCUSS THE ROLE OF ION CURRENTS IN DETERMINING THE SHAPE AND DURATION OF CARDIAC ACTION POTENTIAL

Introduction Selective permeability to various ions is an important characteristic of cell membranes, one that determines myriad cellular functions. In animal cells, ion permeability and the electrical potential generated thereof determines the activity of neurons, myocytes and the like. The electrical potential depends on the concentration of the ions inside and outside any given cell, the permeability of the cell membrane to the ions and the ion channels that are present on the surface of the cell. Cardiac cells also possess different ion channels on their surface. These determine the two types of electrical potentials, namely, resting membrane ...

Definition of Some Terms

- Resting membrane potential: term denoting that Em is about -70mV - Depolarization: reversal of Em due to influx of sodium ions - Sodium (Na+): major extracellular cation - Threshold: minimal stimulus needed to cause an AP - Absolute refractory period: cell membrane insensitive to stimuli. - Potassium (K+): major intracellular cation

Answers to Questions

Describe a synapse, and include definitions of the pre- and post- synaptic neurons. A synapse is an anatomically specialized junction between two neurons, and it is where one neuron alters the activity of another. A presynaptic neuron conducts signals toward a ...

Introduction

Elodea canadensis is a perennial hydrophyte, which is native to the majority of North America and was first recorded in about 1836 from the British Isles (Hackney, 1992). Young plants at first begin with a seedling stem and roots grow in mud at the underneath of water. More adventitious roots arise at intervals along the stem. The leaves are translucent, bright green, oblong, 1-4 mm broad and 6-17 mm long, borne in whorls of three round the stem (Rose, 2006). It lives completely submerged.

Blepharisma is a unicellular ciliate protists genus found in salt and fresh water (Miyake, Harumoto, Salvi, & Rivola, ...

Microbial nutrition is essential in the survival and growth of microorganisms. Talaro and Chess considers several factors which are key players in the survivability of microbes in order to adapt or “inhabit all parts of the biosphere.” Among these factors include nutrients, temperature, pH, water availability, atmospheric gases, light, pressure and other organisms inhabiting the earth. Nutrition in essence is that which chemical substance in the form of nutrients are ingested inside the body such that when assimilated leads to the formation of energy to be used for metabolic activities.

Organisms require organic forming compound elements such as ...

Chapter 4: Prokaryotic Cells and microorganisms

This chapter looks at the morphology, and pathogenic mechanisms of prokaryotic cells and microorganisms respectively. It discusses in detail the structural components, functions of the different organelles of prokaryotic cells as well as feeding and survival mechanisms of prokaryotic microorganisms.

Prokaryotic cells have a specialized cellular structure. Prokaryotes are unicellular and their cells have no cellular organelles, that is, a membrane does not surround their nucleus. These cells contain intricate phospholipids, sterols, and sphingolipids. They are typically 1-5µm in diameter .

Their outer surface is covered by glycocalyx, which is a gel like cellular envelope that provides prokaryotic cells with protection against ...

Energy Storage inform of Lipids

Lipids are a class of natural compounds that are hydrophobic in nature and consist of ketoacyl and isoprene groups. They include sterols, waxes, fats, glycerides, phospholids and fat soluble vitamins such as vitamins A, E and K. Lipids are structural compounds being components of the cell wall but also serve in energy storage and signaling. The signaling function of lipids results from their use in nerve cell axons and as bases for hormones. After digestion and absorption lipids are carried as lipoproteins by blood to the liver which regulates lipid levels in blood. Excess lipids are converted to adipose tissue ...

Introduction

The neurophysiology of nerve pulses in the cell were the subject of the online laboratory experiment in order to better understand neuron communication from inside a cell to the outside of a cell. One of the incredible characteristics of the nervous system is its capability to communicate due to the existence of neurons. Neurons show a measurable response to their environment by producing an electrical signal. We can smell due to olfactory sensory neurons that can directly react to perfume, food or anything with an odor; these odors are the sensory stimuli. The function of the receptor potential is to trigger an ...

Introduction

Therapeutic ultrasound is categorically as any form of ultrasonic procedure where ultrasound is used in advancing therapeutic benefits. Ultrasound is defined as a systematic oscillating pressure wave that has a higher frequency capacity compared to the human hearing frequency range. Its frequency in most cases supersedes the upper limit of the hearing range of human beings .The execution of the procedures is normally under the use of focused ultrasound (FUS) and unfocused ultrasound. Therapeutic ultrasound is used to reduce pain that emanates from body tissues by providing a viable solution to swelling and edema of the tissues. . Secondly, it is used to ...

Antifungal Medications

In dentistry and oral care medicine, antifungal medications are prescribed less compared to conventional analgesic or antibiotics. However, it is mandatory that a clinician or dentist is familiar with common antifungal indications and medications available in the market. Antifungals are used to treat oral candidiasis. Oral candidiasis is known to cause complex oral health problems. Oral and pharyngeal candidiasis is caused by the primary fungal organism Candida albicans. Oral candidiasis is listed as an acquired immunodeficiency syndrome by the Centers for Disease Control and Prevention. Due to imbalances in the oral flora, patients using oral antibiotics could develop case of ...

Lesson 5 Answers:

24.) Plants are classified into four major groups: Bryophytes, Pteridophytes, Gymnosperms and lastly the Angiosperms. Bryophytes are the plants that do not have true vascular systems, which consist of the xylem and the phloem. In this group, includes the mosses, liverworts and hornworts. Together, they are considered as land plants that reproduce their own asexually by producing spores. Spores are produced in the ‘sporangium’ (plural sporangia), a bulb-like structure located at the top of the stalk. It can only be seen through the use of high powered microscope. Because they lack vessels that can bring the nutrients from the roots ...

Membrane transport refers to the mechanisms by which ions and other small molecules move across the lipid bilayer of the plasma membrane. The lipid bilayer of the plasma membrane allows the passage of certain molecules down their concentration gradient. This passage depends on the charge, size and polarity of the molecule. Non-polar molecules and small polar molecules diffuse easily across the cell membrane by the process of simple diffusion. However, it becomes difficult for charged polar molecules to enter the cell even though the concentration of the ion is more outside the cell when compared to the cytosol. At ...

Introduction

Obesity and overweight have been classified as global and serious conditions that have an adverse effect on the human health. Obesity and overweight conditions are defined as excessive or abnormal accumulation of fat that may negatively affect health. In adults the obesity and overweight are measured by the body mass index (BMI), which is simple weight-for-height index (WHO, 2014). The BMI is computed by the ratio of the individual's body weight to the square of body height, indicated in Kg/m2 (WHO, 2014). According to W.H.O., (World Health Organisation), a BMI equal or above 25 is considered as overweight while a BMI ...

Why are lipids important?

Lipids are a form of organic molecules, which are categorized together based on their solubility in non-polar solvents. There are four key lipid groups, which include fatty acids, glycerides, nonglyceride lipids and Complex lipids. Lipids are important since they serve different biological functions, which include storage of energy, source of energy, structural components of the cell membrane, adsorption of vitamins, protection, as well as insulation.

Can the body produce essential fatty acids (EFA’s)? If not, how does thebody obtain these needed lipids?

Essential fatty acids (EFAS) include omega-6 also known as linoleic acid and omega-3 also known as alpha-linolenic acid. The body does not produce them, but they are needed and are used to make other fatty ...

The solution A contained polysaccharides and monosaccharide at the beginning of the experiment. At the end of the experiment, the cell contained the same contents, both monosaccharide and polysaccharides. However, the cell was rigid due to movement of water molecules from the solution in the beaker through the cell membrane of the dialysis tube to the solution inside the cell. At the beginning of the experiment the solution in the beaker was yellow in color (This signified the presence of iodine). On the other hand, the cell content was clear. However, at the end of the experiment the ...

Introduction

The term lipids is used to refer to a group of organic compounds that are naturally occurring and that are all soluble in non-organic solvents such as benzene , chloroform, acetone and ether but not soluble in water. The later characteristic means that lipids can also be defined as amphiphilic or hydrophobic small modules. This amphophilic nature of lipids essentially allows them to be able to form structures such as liposome’s, vesicles or membranes when subjected to aqueous environments. The biological lipids mainly originate from two major build-blocks or biochemical sub-units: isoprene and ketoacyl groups. Another distinct characteristic of lipids ...

Cancer is the abnormal proliferation and differentiation of cells in an abnormal tissue incongruent with the growth pattern of normal cells that persists even after the stimuli that evoked the change is withdrawn. The cell cycle check points at G1, G2 and at the end of metaphase that prevent transmission of genetically damaged DNA fail to occur. Transmission of faulty DNA results in either an abnormal rate of cell division and multiplication or abnormally constituted daughter cells. The genes affected are the normal regulatory genes including growth promoting proto-oncogenes-normal genes that are prone to becoming cancerous on mutation ...

“Abstract”

Cholesterol plays a pivotal role in the fluidity of plasma membrane in cells. Evidence of cholesterol evolution from lanosterol suggests that cholesterol has little sensitivity to changes in temperature as opposed to lanosterol. Simulations also revealed that there is no ld-lo coexistence and 3-phase lines in lipid/lanosterol systems as opposed to lipid/cholesterol systems. The sterol also favors a strong interaction with lipids having saturated acyl chains (Miao et al.) which is a key factor in understanding and characterizing the lipid bilayer model. Based on surface potential measurements, cholesterol and ergosterol reduce the penetration of water into the lipid monolayer. Results revealed that excess ...

Q1 Insolation can be described as the amount of energy of solar radiation received on a certain surface area and recorded in a given time. It is also known as solar irradiation and expressed as daily irradiation when recorded during a day and hourly irradiation when recorded during an hour. Throughout the year, the seasons undergo changes based on the quantity of sunlight hitting the Earth as it circles around the Sun. Seasons occur as a result of Earth tilting on its axis, moving in a loop around the Sun every year. Summer occurs when the hemisphere is angled towards the Sun ...

Webliography

Web Address: http://evolution.about.com/od/Overview/a/Types-Of-Cells.htm Description: According to this we bite, a cell is a basic unit of living organisms. All living organisms have cells. While others are simple unicellular, others are made up of many cells. There are basically two distinct types of cells: prokaryotic and eukaryotic cells. They are fond in different types or organisms. Each type of cell is made up of different organelles. These are specialized in performing different roles. Basically, prokaryotic are the simplest group of cells on earth. Unlike the eukaryotic cells, they are found in single celled organisms such as bacteria and amoeba. These are ...

Simulation of osmosis across the cell membrane using dialysis bags models to measure the direction and the rate of osmosis

Osmosis refers to the process by which the cells exchange their water content with their surroundings (Beckett, 1986). The process is passive just like diffusion only that osmosis involves water only. The water molecules move from a where their concentration is high to a where their concentration is low, through a membrane that is semi-permeable. The permeable membrane only allows water molecules are other small molecules to pass while preventing large and other charged molecules from passing. The pressure that is exerted by the molecules of water that are freely moving in a system is known as the water potential (Kent, 2000). ...

The blood vessels that are involved in carrying oxygenated blood are referred to as arteries. The arteries are involved in carrying the oxygenated blood all through the body starting from the heart. In healthy conditions, the arteries have smooth inner walls and their blood flow through them with ease. There are incidents where the occlusion of the arteries occur, narrowing the artery. The main cause of the artery clogging is a thrombus and atherosclerosis. This is due to the formation of plaques from the various substances that circulate in the blood such as the fat, calcium, fibrin, and cellular waste. ...

Aerobic Cell Respiration

Aerobic Cell Respiration is necessary for the respiration characteristics of life. Every living organism requires energy to use for growth and maintenance. Aerobic Cell Respiration leads to the conversion of biochemical energy into the Adenosine Tryphosphate (ADP). This occurs during catabolic metabolic reactions in which volumes of energy are released as a result of the breakdown of large molecules into small ones (Rich, P. R., 2003). This is an exothermic redox reaction which and it is through it that the living organisms manufacture energy. However, it can only occur if the body is supplied with energy rich foods such as ...

Environmental and Nutritional Requirements of Lactobacillus casei

Lactobacillus species have attracted considerable attention during the past few years due to the health benefits to the gastrointestinal tract when they are added as probiotics to food products such as yogurt and other fermented milk drinks (Broadbent, Larsen, Deibel, & Steele, 2010). In general, Lactobacillus species exhibit very complex nutritional and environmental requirements for optimal growth. Particularly, Lactobacillus casei is a rod shaped, aciduric (prefers acidic environments), facultative (capable of living in aerobic or anaerobic conditions) and mesophilic (temperature range between 15-40°C) lactic acid bacterium. These characteristics allow its isolation from different environments including fermented milk, meat or vegetable ...

Introduction

The basic unit of life is essentially the cell. A cell membrane surrounds all the cells. The cell membrane is thus semi permeable hence this allows certain substances to pass and blocking others into the cell. This cell membrane is composed of phospholipids that are a double layer embedded in proteins. Plant cells on their part contain an additional layer called cell wall that surrounds them. An organelle in cell biology is actually a specialized subunit or structure, which is found within a cell and has a specific function. Therefore, a cell organelle refers to a membrane bound structure or compartment in a cell which performs a ...

Human Immunodeficiency Virus, HIV is a retrovirus, which is a unique virus family consisting of RNA as the genetic material instead of DNA. This genetic material is surrounded by an envelope of lipoprotein. HIV differs structurally from other members of the family retrovirus. It is roughly spherical and has a diameter of around 120 nm. Human Immunodeficiency Virus comprises of two copies of non-covalently joined positive single-stranded RNA enveloped by a conical capsid that consist of the p24 viral protein, which is typical of lentiviruses. Lysine tRNA is reverse transcriptase that is magnesium dependent and is involved in the packaging of both ...

Marburg Virus

Introduction Marburg virus refers to virus of the genus marbugvirus. The virus usually causes the Marburg Hemorrhagic Fever. The virus is said to have originated from Africa and specifically Central and East Africa. The virus got its name from the place where the first outbreak was discovered, Marburg in German. The virus infects both human beings and other animals, especially nonhuman primates. The virus usually lives in the animals hosts, and human being can easily contact the virus from the animals. After the initial transmission of the virus to human beings, the virus can be transmitted among ...

The G- protein coupled receptors (GPCRs) include a group of receptors that still undergoes intense research. Such research occurs at both academic levels and in the pharmaceutical industry. Several advancements occurred recently in the structure of the G- protein coupled receptors. There appeared new crystal structures as well as ground states and active states. Such advancements in the structure of these proteins helped in the further understanding of the receptors especially in the therapeutic fields. It also possesses an immense impact on the GPCR field (Andrew, 2008, pp.6). Several fundamental factors help in the understanding of these receptors. Such ...

Abstract

Water is an important chemical owing to its various uses by living things. Most chemical reactions within the bodied of living things require water in order to occur. It is purported that life evolved from water some 3.8 billion year ago following the organization of inorganic and organic molecule to form as prokaryotic cells. Besides, the well being of a cell is overly dependent of the balance between the water and the dissolved substances in the water. In this regards, the cell can permit water molecules to move in and out of the cell; the process in called Osmosis.

Introduction

In ...

The movement of cholesterol, which is unestrified, is largely due to the activation of the NPC 1 protein. In cases where inactivation of mutation of this protein occurs, one may be suffering from Niemann-Pick type C disease. So what is this disease? Niemann-Pick Type C disease is a serious but rare nuerogenerative disorder. It is very common to children at or approaching adolescence. The disease is estimated to infect one out of every 160,000 children (Patterson 2009). NPC is regarded as a malfunction in the body’s cholesterol metabolism. NPC is also is sometimes referred to as childhood Alzheimer. This ...

Introduction

Selective permeability is a function and a feature of the cell membrane, which is crucial to regulate homeostasis. According to Turksen (132), the plasma membrane function by controlling specific passing of some substances and at the same time hinders entry of some substances into the cell. As high school students, we were curious of a cell membrane could do this function. We, therefore, performed an experiment to test how a chicken eggshell membrane could allow some substances to pass through it while hinders the passage of some substances. We dissolved the eggshell in vinegar. After a thorough reading, the book by Turksen (143), we ...

Pathogenic and Non-pathogenic Organisms

Similarities in both organisms include the fact that both organisms are non-sporulating. Although, not the only metabolite, Salmonella enterica can produce lactate as one of its metabolite while Lactococcus lactis produces lactate. Both organisms are anaerobes, feeding by fermenting substrates (PHAC, 2010). Salmonella enterica ferments glucose while Lactococcus lactis ferments milk. Salmonella enterica is different from Lactococcus enterica in several ways. From gram staining, Salmonella enterica is a gram-positive organism while Lactococcus lactis is a gram-negative organism. At the level of feeding, Salmonella enterica feeds on a wide range of carbohydrates (PHAC, 2010). It is a heterofermentative organism whereas Lactococcus lactis is a ...

How an Animal Cell Survives

Although the animal cell is similar in many ways to eukaryotic as well as some few eukaryotic cells, there are strikingly large differences between them, especially the requirements for survival in various environments (Baitsell, 2008). The animal cell is one of the members of eukaryotic cell category, whose structure is quite complicated by the organelles present as well as the diverse functions they play towards the survival of the cell and the organism in general (Solomon, Berg, & Martin, 2004). The cell structure is defined by a plasma membrane that bounds a number of organelles, all of which function towards the ...

Introduction

Biology is broad and therefore embraces various topics in life that concern living organisms. Micro biology for instance deals with the study of very small organisms that are able to reproduce and sustain their generations. This is where the study of prokaryotes comes into the scene. The contrasting organisms to prokaryotes are referred to as eukaryotes. Contrary to prokaryotes, eukaryotic organisms have complex cell structures. Biology tends to full describe the complete nature of these organisms, their feeding habits, how they reproduce and where they thrive best, that is, their habitats.

Prokaryotes are single celled organisms whose cells lack ...

Aims

1. To observe and investigate the effects of osmosis across the cell membranes of a plant. 2. To investigate the ability of different molecules to diffuse across a selectively permeable membrane.

Introduction

All living cells are enclosed by an outer covering known as plasma or cell membranes. In addition, these plasma membranes serve as barriers between different compartments in the body to confine processes and materials to certain locations. Examples of these processes are diffusion and osmosis which are the main physiological processes that play important roles in the body. Diffusion can be defined as the process by which molecules move ...