...molecules and proteins. The plasma membrane is selectively permeable and regulates which molecules are allowed to enter and exit the cell. Definition of Plasma membrane. All cells are surrounded by a plasma membrane. The membrane is composed of a phospholipid bilayer arranged back-to-back. The membrane is also covered in places with cholesterol molecules and proteins. The plasma membrane is selectively permeable and regulates which molecules are allowed to enter and exit the cell. Human cells have a membrane that holds the contents together. However, this membrane is not just a sack. It has receptors that identify the cell to other cells. The receptors also react to substances produced in the body and to drugs taken into the body, selectively allowing these substances or drugs to enter and leave the cell. Reactions that take place at the receptors...
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...Atenolol is a Beta adrenoceptor Antagonist which is more efficient in Blocking Beta 1 receptors. It is one of the most used drugs for treating hypertension since it is a cardioselective drug. It lowers the blood pressure and the heart rate and may be safe for asthmatics. The main indication is for angina pectoris, hypertension and arrhythmias. Its main action is to prevent sympathetic vasoconstriction and to reduce prostatic smooth muscle tone. One of the main problem with taking atenolol is that a daily dose is not sufficient and the behavior of the patient towards taking the drug continuously is dependent on this. Doxazosin is an Alpha 1 Blocker. It selectively blocks alpha 1 receptors in arterioles and venules. It dilates both resistance and capacitance vessels which result in a reduction of arterial pressure. It produces less reflex tachycardia when lowering blood pressure. Retention of salt and water occurs with the intake of these drugs, so a diuretic must be taken in order to counteract these effects. Thiazide diuretics should not be given to patients with hyperlipidemia because it will just worsen the condition because thiazide diuretics deplete sodium and potassium (Ames). Hydralazine dilates arterioles but not veins. The bioavailability is low with an estimation of 25% because it is rapidly metabolized by the liver during the first pass. It is mainly used in severe hypertension and works better in combination with Nitrates. It is effective in heart failure. It has...
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...003 Chapter 03 Cell Biology and Genetics Student: ___________________________________________________________________________ 1. The structural and functional unit of all living organisms is the A. ribosome. B. cell. C. organ. D. organelle. E. plasma membrane. 2. All of the chemical reactions within a cell are known as cell A. reproduction. B. metabolism. C. communication. D. inheritance. E. movement. 3. Cells produce and respond to chemical and electrical signals as a means of A. communicating. B. metabolizing. C. reproducing. D. synthesizing. E. using energy. 4. Which of the following is NOT a characteristic function of a cell? A. reproduction and inheritance B. metabolism and energy use C. movement D. synthesis E. communication 5. Which of the following could be used to study general features of cells? A. a magnifying glass B. scanning electron microscope C. transmission electron microscope D. binoculars E. light microscope 6. In order to study in detail the anatomy of internal cell parts, it would be best to use A. x-rays. B. flashlights. C. a transmission electron microscope (TEM). D. tissue cultures. E. a scanning electron microscope (SEM). 7. The plasma membrane A. separates the nucleus from the rest of the cell. B. is a rigid protein membrane. C. is not permeable. D. has a single layer of phospholipids. E. regulates movement of materials into and out of the cell. 8. The environment outside the plasma membrane is most appropriately...
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...CHEMICAL CONVERSIONS Acylation Acylation (rarely, but more formally: alkanoylation) is the process of adding an acyl group to a compound. The compound providing the acyl group is called the acylating agent. These are used to form aryl ketones. Because they form a strong electrophile when treated with some metal catalysts, acyl halides are commonly used as acylating agents. For example, Friedel-Crafts acylation uses acetyl chloride (ethanoyl chloride), CH3COCl, as the agent and aluminum chloride (AlCl 3) as a catalyst to add an ethanoyl(acetyl) group to benzene: The mechanism of this reaction is electrophilic substitution. Hydrolysis While solvolysis often refers to an organic chemistry context, hydrolysis is very common in inorganic chemistry, where aqua complexes of metal ions react with solvent molecules due to the Lewis acidity of the metal center. For example, aqueous solutions of aluminium chloride are acidic due to the aqua-aluminium complex losing protons to water molecules, giving hydronium ions which lowers the pH. In organic chemistry, hydrolysis reactions often give two fragments from an initial substrate. For example, the hydrolysis of amides give carboxylic acids and amines; the hydrolysis of esters give alcohols and carboxylic acids. Alcoholysis An example of a solvolysis reaction is the reaction of a triglyceride with a simple alcohol such as methanol or ethanol to give the methyl or ethyl esters of the fatty acid, as well as glycerol. This reaction is...
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...* Cholesterol contains two angular methyl groups: the C-19 methyl group is attached to C-10, and the C-18 methyl group is attached to C-13. * The C-18 and C-19 methyl groups of cholesterol lie above the plane containing the four rings. Steroids with 8 to 10 carbon atoms in the side chain and an alcohol hydroxyl group at C-3 are classified as sterols. Much of the plasma cholesterol is in the esterified form (with a fatty acid attached at carbon 3), which makes the structure even more hydrophobic . FUNCTIONS Cholesterol is the most abundant sterol in humans and performs a number of essential functions. For example- * It is a major constituent of the plasma membrane and of plasma lipoproteins. * It is a precursor of bile salts, * It is a precursor of steroid hormones that include adrenocortical hormones, sex hormones, placental hormones etc * Also a precursor of vitamin D, cardiac glycosides, Sitosterol of...
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...Congenital adrenal hyperplasias (CAH) are autosomal recessive disorders characterized by impaired synthesis of cortisol and accumulation of cortisol precursor. Biosynthesis of this glucocorticoid occurs in the zone fasciculata of the adrenal cortex under the influence of adrenocorticotropin hormone (ACTH), and requires five functional enzymes in order to convert cholesterol to its final product. Cortisol levels below threshold, result in an blockage of feedback inhibition of ACTH secretion, causing an increase in ACTH and enlargement of the adrenal cortex. Treatment is primarily focused on reducing long term consequences of glucocorticoid deficiency, and normalize synthesis of aldosterone and androgens. CAH is caused by an inherited defect...
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...This is mechanism which keeps the total body cholesterol under control. During this process apolipoprotein APOA1 (pre-βHDL) eliminates the cholesterol and send to liver for excretion. New studies show that lymphatic vessels play an essential role in reverse cholesterol transport mechanism4. This mechanism can be further studied, and new line of therapeutic drugs can be created which reduces ASCAD Reference 1) Milasan, A., Dallaire, F., Mayer, G., & Martel, C. (2016). Effects of LDL Receptor Modulation on Lymphatic Function. Scientific Reports, 6(1). doi:10.1038/srep27862 2) Mishra, S., Somvanshi, P. R., & Venkatesh, K. V. (2014). Control of cholesterol homeostasis by entero-hepatic bile transport – the role of feedback mechanisms. RSC Adv.,4(103), 58964-58975. doi:10.1039/c4ra09397f 3) Rashid, S. et al. Decreased plasma cholesterol and hypersensitivity to statins in mice lacking Pcsk9. Proceedings of the National Academy of Sciences of the United States of America 102, 5374–5379, doi: 10.1073/pnas.0501652102...
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...and out of the nucleus (through nuclear pores). When the chromosomes are not diving they are in the form of chromatin, the nucleus contains the chromatin. It contains DNA. There are two forms of chromatin: euchromatin and heterochromatin. Euchromatin contains inactive DNA and heterochromatin inactive. Michael Kent (2000) explains ‘the nucleus also contains one of more nucleoli. These manufacture ribosomes’. In the nuclear envelope in a substance called nucleoplasm or karyoplasm and it similar to cytoplasm. It is mainly water, enzymes and dissolves salts. The nucleus has a nucleolus which is membrane-less and is made of RNA and proteins. Thoughtco (2017) explains ‘The nucleolus contains nucleolar organizers, which are parts of chromosomes with the genes for ribosome synthesis on them’. Thoughtco further explains how the nucleolus helps to ‘synthesize ribosomes by transcribing and assembling ribosomal RNA subunits’. In protein synthesis, sub-units will join and become a ribosome. Peroxisome Peroxisomes are small organelles, that are membrane bound and are cytoplasmic. They are found in both animal cells and plant cells. They are responsible for a lot of metabolic activities, breaking down fatty acids and amino acids. In some cells they are responsible for lipid break-down. The enzymes produce a biproduct, hydrogen peroxide, this can be dangerous for the cells so peroxisomes will isolate it. An enzyme called catalase is able to break down hydrogen peroxide. Peroxisomes protect the...
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...Why Does The Same Drug Affect People Differently? By: Brianna Morse Basic Genetics and the Inheritance of Genes What are Genetics? Have you ever wondered why you have your mother’s eyes of your father’s hair color? The simplest answer for this would be genetics. Genetics is the study of heredity or inheritance. Genetics helps to explain how traits are passed from parents to their young. Parents pass traits to their young through gene transmission (for example hair and eye color, shape of ears, cheek bones, and mouth shape). Genes are located on chromosomes and consist of DNA (A chromosome is a long, stringy aggregate of genes that carries heredity information (DNA) and is formed from condensed chromatin). They contain specific instructions for protein synthesis. A protein synthesis is the process in which cells build proteins, and a protein is a dietary component that helps with things such as building strong muscles and other parts of the body. Genetic Inheritance of Single Gene Disorders The genetic inheritance process can be useful in predicting what sorts of disorders or mutations that an offspring will have in the future. This can basically be explained and shown in a punnett square. A punnett square is a tool that helps to show all possible combinations of an offspring in a cross of parents the DNA with known genotypes in order to predict the probability of their offspring possessing certain sets of traits. It makes a grid using letters, capital letters to represent...
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...Biology 119, Spring 2015 Review sheet for Exam 1 The exam is worth 100 points total. It will consist of approximately 47 multiple-choice questions worth 2 point each and 3-4 short essay questions. Bring a scantron and pencil to the exam. The best way to study is to review the posted lecture notes. I suggest printing of a blank copy and filling them in referring to your book and notes as little as possible. Continue this process until you can fill them in without assistance. Exam 1 will cover chapters 1-3 and 6. 1. How long have microbes been on the planet? How has this affected the evolution of more complex species? a. Microorganisms are the foundation for all life on earth b. They have existed on this planet for about 3.5 billion years c. Over time plants, animals, and modern microorganisms evolved from them 2. Describe some of the negative impacts of microbes. d. Disease epidemics- an infectious disease that affects large numbers of people in a given area e. Chronic disease caused by bacteria i. Many disease once thought caused by environmental stressors actually caused by bacteria 1. Example: gastric ulcers a. Causative agent – Helicobacter pylori f. Examples: ii. Black Plague (Yersinia pestis bacterium)- killed 25 million Europeans between 1346-1350 iii. Influenza 1918-1919 killed more than all the wars combined iv. Cholera-vibrio cholerae ...
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...Food Additives Taking this class has been very eyes opening, I have never give much thought to the kind of additives that is included in our foods. The Center for Science in the Public Interest list of food additives was a great source. It is very sad to see that our government allows companies to produce products or ingredients that is use in our foods that can cause or other serious health problems for most of us. Some of the ingredients can cause Cancer, or increase blood pressure or other ailments. The bottom line is consumers should be aware of what they are putting in their bodies. We should not let the FDA tell us what is safe for us to consume. They leave the final decision to food manufactures as to what is safe for us. More reason why we should follow Michael Pollan book “food Rules” and eat natural food, more plant base food. This class has given me an education in nutritional information I will use to further my fitness goal and to continue to make sure my daughter has a solid foundation in nutrition. I will continue to read labels now that I know the meaning of the additives on the label. I was required to take a science class and because of my interest in health and fitness I selected this class and I am very glad I did. I am walking away with information that I will use for the rest of my life. Food item: Corn Bread mix Version of food: Penguin Natural Foods Ingredient | Type of Additive | | Thiamin Mononotrate | Vitamin B | It...
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...activities crucial for maintaining the biosphere, they also exert significant impacts on human life’ discuss this statement fully using named examples. Prokaryotes are unicellular microorganisms without a nucleus; they are divided into two groups’ Eubacteria and Archaebacteria. These microorganisms are very small and invisible and are known as the most dominant species on the earth’s biosphere as they are found almost everywhere on earth, they are predominately, found in our body’s immune system, and they are mainly responsible for the decomposition of dead matter which in return benefits both plants and animals. They are found in the air that we breathe, in the food that we eat, in deep seas, in cold and hot temperatures, sea corals, in salt water, fertile soils and in short, they are so diverse in their form of habitation and adaptation, as different types of bacteria adapt to different types of environments in different forms of life. However, bacteria are grouped according to their uniqueness, features, structure, functions, and contribution to human life. Prokaryotes are so beneficial to us because they act as defences to protect us from various diseases. The essay will examine the significant impact of prokaryotes to human life. The word bacteria may be frightening to most of us; in many cases it is often associated with many negative and harmful aspects such as infectious diseases, dental decay, mould and smell. But bacteria provide us with both positive and negative...
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...effect on the mesolimbic reward pathway. Formulations COCAINE HYDROCHLORIDE Topical Solution CIIRx only [Lannett Company, Inc.] Each mL contains:Cocaine hydrochloride 40 mg or 100 mg As aqueous solution.The topical solution contains the following inactive ingredients: citric acid, D&C Yellow No. 10, FD&C Green No. 3, sodium benzoate, and water. Methamphetamine Methamphetamine (USAN) also known as metamfetamine (INN),meth, ice, crystal glass, tik, N-methylamphetamine, methylamphetamine, and desoxyephedrine, is a psychostimulant of the phenethylamine and amphetamine class of psychoactive drugs. Methamphetamine occurs in two enantiomers, dextrorotary and levorotary; dextromethamphetamine possesses the well-known psychostimulant effects of the drug, while levomethamphetamine is CNS-inactive. Although rarely prescribed, dextromethamphetamine is approved by the U.S. Food and Drug Administration (FDA) for the treatment of ADHD and obesity under the trade name Desoxyn, while levomethamphetamine is a non-prescription over-the-counter nasal decongestant. Formulations Methamphetamine hydrochloride tablets contain 5 mg of methamphetamine hydrochloride, USP for oral administration. Inactive Ingredients Corn starch, lactose monohydrate, stearic acid and talc. Cannabis Cannabis, also known as marijuana (from the Mexican Spanish marihuana), and by other names, is a preparation of the Cannabis plant intended for use as a...
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...Vitamins | Description | Source | Difficiency | Vitamin A | Vitamin A is a group of unsaturated nutritional organic compounds, that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids, among which beta-carotene is the most important.[1] Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system and good vision | Liver, orange, ripe yellow fruits, leafy vegetables, carrots, pumpkin, squash, spinach, soy milk, milk | Night-blindness,Hyperkeratosis, and Keratomalacia[8 | Vitamin B1(Thiamine) | is a water-soluble vitamin of the B complex. First named aneurin for the detrimental neurological effects if not present in the diet, it was eventually assigned the generic descriptor name vitamin B1. Its phosphate derivatives are involved in many cellular processes. The best-characterized form is thiamine pyrophosphate (TPP), acoenzyme in the catabolism of sugars and amino acids. Thiamine is used in the biosynthesis of the neurotransmitter acetylcholine and gamma-aminobutyric acid (GABA). In yeast, TPP is also required in the first step of alcoholic fermentation. | Pork, oatmeal, brown rice, vegetables, potatoes, liver, eggs | Beriberi,Wernicke-Korsakoff syndrome | Vitamin B2 (Riboflavin) | is an easily absorbed colored micronutrient with a key role in maintaining health in humans and other animals. It is the central component of the cofactors FAD and FMN, and is therefore required by all flavoproteins...
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...called sterols. Sterols (also known as steroids) are compact hydrophobic molecules that contain four fused hydrocarbon ring and a number of different functional groups. Cholesterol is an important component of the plasma membranes in animal cells. It is essential for the production of sex hormones, producing bile salts, converting sunlight into vitamin D, and the up-keeping/forming of cell membranes. The leading organ responsible for producing cholesterol is the liver. Before cholesterol is released into the bloodstream the liver packs it with proteins and other compounds. This forms a lipoprotein. Lipoproteins are formed so that cholesterol can be transported through the bloodstream to where it is required. The two main types of lipoproteins are high-density...
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