Parental education Essay Example | Topics and Well Written Essays - 1250 words

Parental education - Essay Example The failure of many adults to succeed is rooted in the poor parenting skills of those who raised them, thus suggesting that required parental education would benefit society as a whole. A society has the right and the obligation to define how its members will interact within the ideological framework of its culture. One of the biggest problems in the United States is that most people do not have generations of ancestors who came before them on which to base their cultural belief systems. Therefore, the way in which parents pass their heritage to their children is often convoluted and without social structure, the design of the community not based upon generations of cultural belief systems, but a patchwork of concepts that do not inform those who are trying to find a way to raise their children on exactly what is best in regard to their future. As witnessed in the disrupted families within the two parallel stories of Wes Moore, when the struggle to survive creates a gap between what is life and what one thinks life should be, the frustration can lead children to some very poor decisions that can impact the rest of their lives. Because of the gaps that leave many children struggling to acculturate within their own native society, the concept of parent education is one way that this social problem can be combated. The difficulty, however, is that parenting is a complex activity that is comprised of a number of roles and a wide path of responsibilities. According to Chase-Lansdale and Pittman, list the number of functions of a parent as including â€Å"nurturing, discipline, stimulation, values, activities, and routines† (167). In the process of promoting good parenting skills within those who were at a socio-economic level to receive state assistance for their families, parenting classes have been a part of the reforms. Chase-Lansdale and Pittman have concluded that programs with generous work supports and flexible work requirements have lead to different choices within the family and have promoted, not only better parenting skills, but more stable marriages and less violence between partners which has lead to overall natural better parenting (167). The following factors in the methods of parenting have been instrumental in creating children who make better life choices: warmth and responsiveness, control and discipline, cognitive stimulation, modeling, gate keeping, and family routines and traditions (Chase-Lansdale and Pittman 168). The characteristics of a parent are central to the way in which the parent will provide positive examples of these factors. Chase-Lansdale and Pittman state that â€Å"Single mothers tend to have less positive interactions with their children and provide less firm and consistent discipline as compared with mothers in two-parent households†¦primarily because single mothers have more stressors in their lives† (171). This suggests that parents who are experiencing high levels of stress are not as capable of focusing their positive life experience on their children. According to Carlson and Tanner, parents are the â€Å"primary socialization agents for children†, thus the way a parent approaches life will be passed down to children,

Politics Comment 1 Essay Example | Topics and Well Written Essays - 750 words

Politics Comment 1 - Essay Example â€Å"Even after visiting the likely hiding places around Baghdad, the coalition found no convincing proof that Iraq retained stocks of chemical and biological weapons, or that Saddam had been trying to build a nuclear bomb† (Richie, p. 91). And still American troops remain in Iraq and as a result terror is being felt by the people, not from a dictatorial regime, but from being unnecessarily caught up in the crossfire between insurgents and American troops. U.S. invasion of Iraq has been an instrument of manipulation with underlying reasons not related to discovering and disarming weapons of mass destruction. â€Å"U.S. soldiers has no right to occupy a sovereign nation, outside of international law, and doubly so because it was done under false pretenses† (Tremblay, p. 203). Such false pretenses, experts claim, mask the ulterior motive of the U.S. of wanting to maintain control over Iraqi oil fields and to placate political conservatives who want to make the Middle Eas t safe for Israel (Mueller, p. 137). When the U.S Congress authorized the sending of troops to Iraq, it agreed to do so in order to â€Å"defend the national security of the US from the threat posed by Iraq† (Congressional Resolution 296-133 in the House; 77-23 in the Senate, as quoted by Levin, Editorials). With the fall of Saddam Hussein, Iraq no longer poses a threat to US security. Many experts argue that when illegal troops occupy a country, any violent means adapted by the country’s citizens to depose illegal occupants can be classified as guerrilla warfare. Guerrilla warfare is a war waged by the people to express their protest and outrage against forces that threaten their independence and sovereignty. â€Å"It is a defensive type of war against a foreign invader† (Eland, as quoted by Knickerbocker â€Å"Specials†). And interest groups emphasize that this type of warfare usually does not stop until the

Biological Causes of Cancer and Effects

Biological Causes of Cancer and Effects Cancer refers to a set of diseases characterized by the uncontrolled proliferation of cells into a different form against the normal complement of the organism (Kufe Holland, 2003). There are two types of tumors; one is unremitting proliferation of cancer cells develops into tumor tissues and may multiply across to other organs via circulatory systems resulting in metastasis known as malignant tumors and second one those without malignant properties, which are self-limiting, noninvasive and do not metastasise, known as benign tumors. Around 90% of deaths from cancer are due to the metastases (Box Html, 2008). Cancer may concern humans of all ages. According to figures from World Health Organisation (WHO), cancer is the second most mortal disease after cardiovascular diseases. In 2010, around 5.5 million people in India were died due to cancer. 71% cancer deaths occurred in both men and women aged of 30-69 years. The three most common fatal cancers were oral (including lip and pharynx), stomach, and lung (including trachea and larynx) in men, and cervical, stomach, and breast in women. About 30% of cancer deaths are due to high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco and alcohol use. Hence, the medical needs for cancer remain one of the most demanding areas in scientific research (Dikshit et al., 2012; Ferlay et al., 2007). Cancers are first and foremost an environmental disease with 90–95% of cases due to modification in lifestyle and environmental factors and 5–10% due to genetics mutation (oncogenes, tumour suppressor genes and DNA repair genes). Cancer is caused by physical carcinogens (ultraviolet and ionizing radiation), chemical carcinogens (asbestos, components of tobacco smoke, aflatoxin and arsenic), and biological carcinogens (infections from certain viruses, bacteria or parasites). Common environmental factors leading to cancer death include: tobacco (25–30%), diet and obesity (30–35%), infections (15–20%), radiation, stress, lack of physical activity, and environmental pollutants. These environmental factors cause abnormalities in the genetic material of cells. There are certain risk factors for cancers which consist use of Tobacco, alcohol, unhealthy diet and physical inactivity are the main cancer risk factors worldwide (Rayl and Lewis, 2001; Bahls and F ogarty; 2002; Gibbs; 2003). Chronic infections from hepatitis B (HBV), hepatitis C virus (HCV) and some types of Human Papilloma Virus (HPV) are leading risk factors for cancer in low- and middle-income countries. Cervical cancer, which is caused by HPV, is a leading cause of cancer death among women in low-income countries (Newman and Cragg, 2007). It is very unfortunate condition when cancer has been diagnosed; there are a number of treatments available. As cancer refers to a class of disease, it is unlikely that one single cure for all forms of cancer is possible (Pazdur, 2001; Illidge, 2008). The most common methods include surgery, chemotherapy (with one or more cytotoxic antineoplastic drugs), radiation therapy (ionizing radiation). There are other methods of treatment such as targeted therapies (monoclonal antibody therapy), immunotherapy (enhancing, or suppressing an immune response) and hormonal therapy (Goldenberg, 2002; Rosenberg et al., 1986; Byar and Corle, 1988). New methods, immunotherapy have the advantage to minimizing the adverse effects, in this targets specific antigen solely expressed by tumor cells, only target cancer and not the healthy cell population. According to a report of World Health Organization, more than 80% of world’s populations depend on traditional medicine for their primary health care needs (Farnsworth, 1994; Duraipandiyan et al., 2006). Plants have a long history of use in the treatment of cancer and it is significant that over 60% of currently used anti-cancer agents are come from natural source. Naturally occurring drugs that are part of the war against cancer include vinca alkaloids (vincristine, vinblastine, vindesine, vinorelbine), taxanes (paclitaxel, docetaxel), podophyllotoxin and its derivative (etoposide, teniposide), camptothecin and its derivatives (topothecan, irinothecan), anthracyclines (doxorubicin, daunorubicin, epirubicin, idarubicin) and others. In fact, half of all anti-cancer drugs approved internationally were either natural products or their derivatives and were developed on the basis of knowledge gained from small molecules or macromolecules that exist in nature (Cragg et al., 2005; Cr agg et al., 1997). In between 2001 and 2005, 23 new drugs derived from natural products were introduced for the treatment of disorders such as bacterial and fungal infections, cancer, diabetes, dyslipidemia, atopic dermatitis, Alzheimer’s disease and genetic diseases such as tyrosinaemia and Gaucher disease out of these 4 drugs have been approved as anti cancer agents. The approved anti cancer agents in 2002 doxorubicin, in 2002 estradiol, in 2004 cholorophyll and l- aspartic acid and taxol nanoparticles in 2005 (Butler, 2005). Three new drugs also introduced in 2007 originate from microbial sources for the treatment of cancer is marine alkaloid trabectedin, epothilone derivative ixabepilone and temsirolimus (Newman et al., 2003). Nature is an attractive source of new therapeutic candidate compounds as a tremendous chemical diversity is found in millions of species of plants, animals, marine organisms and microorganisms as potential anti-cancer agent (Bailly, 2009; Butler, 20 04; Bhanot et al., 2011). There were various biological mechanisms for controlling the cancer, out of it apoptosis and cell cycle inhibition are important one. Apoptosis is the process of programmed cell death (PCD) that may perhaps occur in multicellular organisms. In distinction to necrosis, which is a form of traumatic cell death that outcome from acute cellular injury, apoptosis generally confers advantages during an organisms life cycle. Biochemical events escort to characteristic cell changes (morphology) and death (Furuya et al., 1994). There are numerous pathways and signals lead to apoptosis, but there is only one mechanism that in fact causes the death of a cell (Meikrantz W, Schlegel; 1995). Subsequent to a cell receives stimulus, it undergoes planned degradation of cellular organelles by activated proteolytic caspases. A cell undergoing apoptosis shows a distinguishing morphology (Alenzi; 2004): The breakdown of the proteinaceous cytoskeleton caused by caspases which shown characteristic cell shrinkage and rounding. The cytoplasm appears dense, and the organelles emerge tightly packed. A process of pyknosis (a hallmark of apoptosis) in which chromatin undergoes condensation into compact patches in opposition to the nuclear envelope. The nuclear cover becomes broken down and the DNA inside it is split in a process known to as karyorrhexis. The nucleus breaks into a number of separate chromatin bodies or nucleosomal units as a result of the degradation of DNA. The cell membrane shows uneven buds known as blebs. The cell breaks together into several vesicles called apoptotic bodies, which afterward phagocytosed. Figure 1.1: Apoptosis in sequence: A) normal resting cell; B) cell volume is lost and chromatin clumped; C) blebbing process; D) chromatin collapsed to the margins of the nuclear envelope; E) nucleus clumped into a black hole; F) cell breaks down into apoptotic bodies; and G) apoptotic bodies ingested by macrophage. Cell cycle consists of two successive periods, that characterized by DNA replication and isolation of replicated chromosomes into two separate daughter cells. The cell cycle divided into five phases: G0, G1, S, G2, and M. Cell division, or cytokinesis, occurs through the M (mi ­tosis) phase, and is preceded by a prepa ­rative phase, or interphase, that includes G0, G1, S and G2 (Fig. 2). DNA replication occurs in a specific part of the interphase, the S (synthesis) phase, which is preceded by a gap called G1, where the cell prepa ­res for DNA synthesis, and followed by G2, during which the cell prepares for mitosis. Figure 1.2: A diagrammatic view of cell cycle indicating formation of two cells from one cell The vast preponderance of the cells are able to di ­vide but do so only when appropriate to re ­place damaged or dead cells. In fact, cells in G0 account for the major part of the non-growing, non-proliferating section of the human body, being essentially arrested in their growth. Cells in G0 can often be sti ­mulated to enter the cell cycle by external growth signals such as growth factors and hormones that bind to cell surface recep ­tors and then convey the signal from the plasma membrane to the nucleus, a pro ­cess known as signal transduction(Sherr, 1994; Ostsubo et al., 1995; Cerveira et al., 2012). The plant Aerva lanata L. belonging to family Amaranthaceae have been used for very long times in traditional system of medicine as diuretic and in lithiasis. Besides the traditional uses the plant were reported numerous pharmacological effects viz. diuretic (Udupihille and Jiffry, 1986), anti inflammatory (Vetrichelvan et al., 2000), anti-microbial, cytotoxic (Chowdhury et al, 2002), anthelmintic, demulcent (Pullaiah and Naidu, 2003), nephroprotective (Shirwaikar et al., 2004), anti-diabetic, anti-hyperglycaemic (Vetrichelvan and Jegadeesan, 2002; Deshmukh et al., 2008), expectorant, hepatoprotective (Manokaran et al., 2008), hypoglycemic, anti-hyperlipidemic (Krishnan et al., 2009), anti-parasitic and anthelmentic activities (Anantha et al., 2010), anti cancer activity was carried out against Daltons Ascitic Lymphoma (DAL) cell lines which show significant cancer control of the same (Rajesh et al., 2011). Beside this vast studies were carried out by various researchers to showing i mportance of Aerva lanata L. which includes finger printing chromatographic technique analysis of steroids, terpenoids, flavanoids and glycosides (Yamunadevi et al., 2011a; Mariswamy et al., 2011a; Yamunadevi et al., 2011b; Mariswamy et al., 2011b). As per previous studies phytoconstituens possessing anti-oxidant properties are believed to prevent or slow down the occurrence of disease such as cancer. In recent years, a large investigation on different classes of imidazo thiadiazoles has been done. Many of them were found to possess definite pharmacological activity. The fusion of a imidazole ring with a 1,3,4-thiadiazole nucleus give rise to a class of heterocyclic systems containing a bridgehead nitrogen atom known as imidazothiadiazoles. Imidazo[2,1-b][1,3,4]thiadiazole derivatives were first discovered in the early 1950s and, since then, the research work on heterocyclic system has led to significant developments in their chemistry and biology. The planar and rigid heteroaromatic imidazo[2,1-b][1,3,4]thiadiazole ring system have interesting physicochemical and biological properties, because of the presence of four hetero atom and two condensed heterocycles with different Ï€-conjugation. Imidazo[2,1-b][1,3,4]thiadiazoles ring systems have been extensively studied and so far, a variety of biological activities have been reported for a large number of their derivatives such as antitubercular, antibacterial, anticancer, anthelmintic, antifungal, anticonvulsant, anti-inflammatory, analgesic, antipyretic, local anaesthetic, diuretic, antileishmanial and herbicidal activities. In addition, they have been reported to selectively inhibit several therapeutic receptors and enzymes, extending their applications in modern drug design (Jadhav et al., 2008). So the present study was designed to evaluate the cytotoxic potential of the plant Aerva lanata L., isolation and characterization of phytoconstituents as well as preparation of their various novel derivatives as potential anticancer agents (Khazi et. Al., 2011).

Attending Melba Beals Event Essay -- Civil Rights Little Rock Nine

I attended an event commemorating a very heroic woman’s actions. Civil rights activist Melba Beals, author of Warriors Don’t Cry, was one of the Little Rock Nine who helped to integrate an all-white Arkansas public high school in 1957. However, this was not a very easy task. She attended school amidst constant harassment, violence, and threats. Her efforts helped shape the civil rights movement and earned her America’s top civilian honor, the Congressional Gold Medal. I found her to be very inspiring, witty, and brave. The event allowed us to hear her perspective on growing up at such a volatile time, and to learn about her unique and rich past. This event was held in the Illini Union, a building on the University of Illinois’ campus where students and faculty work, study, and relax. Very often events such as this one are held to add a diverse flavor and special treat to the already enriching university. This presentation was held in the ballroom on the second floor. This room is a beautifully decorated large hall where many various events take place from dances to speeches. The fact that the event was held in this room shows the importance of Melba and the seating needed to accommodate such a large-scale event. The event was extremely crowded, and many different nationalities and cultures were represented, which was quite surprising to me. I would have imagined only finding African-Americans and whites at an event like this, but to my surprise almost every culture was represented in the audience. Through careful observation I noticed that the composition of the audience was mainly female, college and middle aged. I did notice that there were many families that came together, which was very nice... .... It made me proud of them and for them. From attending this lecture I have a greater sense of appreciation for all the women of color who have made a difference, because now I know how many obstacles they had to overcome to achieve their goal. After seeing her speak I felt extremely enriched and honored to have had the chance to hear someone like her speak in front of me. I felt a sense of pride for her. It was an odd moment. I felt like I was directly connected to her as well as to everything that she was saying. I could feel her pain, sorrow, triumph, and happiness all at once. It is not everyday that someone attempts to de-segregate their high school at a time when African-American people had no right to do something like this whatsoever. I am very much looking forward to reading her book now. I am very interested in finding more out about her life.

Biology By2 Revision

Parasitic Nutrition 21 May 2011 10:43 = organisms that live on or in another organism obtaining nourishment at the expense of the host and causing harm. Gut parasite (Taenia solium) = tapeworm Primary host = human (eat uncooked infected pork) Secondary host = pig (drainage channels contaminated by human faeces) Adaptations†¦ – Suckers & hookers (attachment) – Body covering (immune responses) – Thick cuticle (inhibitory substances = enzymes) – Simple body systems (reproduction) – Very thin & large surface area (food absorbed over whole body surface = diffusion) – Male & female sex organs (gut can only accommodate 1 tapeworm) – Number of eggs produced (increase chance of survival) – Eggs have resistant shells (survive until eaten) Dormant embryos can form cysts in organs – damage surrounding tissue BY2 revision Page 1 Adaptions to different diets 21 May 2011 10:53 Reptiles & Amphibians = swallow food whole Mammals = cut up and chew (palate separates nasal cavity & mouth – kept in mouth longer) Carnivore = short gut (easily digest protein) Herbivore = long gut (p lant digestion difficult) Dentition Mechanical digestion = easier to swallow & increases surface area for enzyme action Herbivore Incisors Canines Lower jaw, cuts against horny pad (upper jaw) Indistinguishable from incisors Carnivore Sharp (tear flesh from bone) Large, curved, pointed = seizing prey, killing & tearing flesh Carnassial (slide past each other = garden shears) molars = cutting/crushing) Vertical (open wide to capture & kill prey) Not horizontal (dislocation) Jaw muscles = well developed/powerful (grip firmly on prey/crush bones) Cheek teeth Interlock. (W into M) Worn down = sharp enamel ridges (efficiency). Open roots (grinding) Jaw movement Other Circular grinding. Horizontal plane Diastema = gap between front & side teeth. Tongue moves cut grass to grinding surfaces (cheek teeth) Ruminants Produce most protein eaten by humans eg. Cows/sheep Mutualism/Symbiosis = close association between members of 2 species, both derive some benefit from the relationship. – Can't digest cellulose (no cellulose enzymes) – Cellulose-digesting bacteria live in gut of cow – Separated = food left long enough for digestion, bacteria isolated (optimum pH & conditions) Cellulose digestion†¦ – Grass chopped (teeth), saliva, cud formed, swallowed – 1st stomach = cellulose digesting bacteria (glucose = fermented – organic acids into blood. Waste = co2 & methane – Cud into next region, regurgitated & chewed again – 3rd stomach = water absorption – 4th stomach (‘normal' stomach) = protein digestion – Small intestine = absorption Rumen = greater variety of mutualistic organisms than in caecum More efficient = more complete breakdown of cellulose Bacteria = source of protein when dead BY2 revision Page 2 Digestion 21 May 2011 11:35 = the break down of large insoluble molecules into smaller soluble molecules. Physical & chemical. Food passes through alimentary canal where it is digested & absorbed into the body. Digestive enzymes = hydrolases (catalyse hydrolysis of substrate – addition of water) – Carbohydrates (polysaccharides) > disaccharides > monosaccharides (Amylase = maltose >glucose) – Proteins >polypeptides >dipeptides >amino-acids (peptidase = endo/exo) – Fats > fatty acids & glycerol (lipase) Mouth (buccal cavity) – Mechanical digestion (teeth) – Saliva = salivary lands (mucus, salivary amylase & mineral ions = optimum pH – slightly alkaline) = lubrication & some protein digestion (amylase = starch > maltose) – Swallowed as bolus Oesophagus – Peristaltic contractions (longitudinal & circular muscles = not under conscious control) – Occurs all way through alimentary canal Stomach = muscular sac (2 sphincter muscles = cardiac & pyloric keep food in stomach) – Muscles in stomach wall contract rhythmically (mix food with gastric juice = secreted by stomach wall) – Gastric juice = optimum pH of enzymes (pH2. 0), kills most bacteria, peptidase enzymes = protein > polypeptides Pepsinogen (inactive) = activated by HCl to active peptidase enzyme – Mucus = form lining (protect wall from enzymes & acid/assist movement) – Food leaves as chyme – Purpose of HCl = optimum pH for enzymes, kill microbes, activate pepsinogen (pepsin) Gastric glands = peptic/chief cells (p epsinogen = inactive until HCl), oxyntic (secretes HCl) & goblet cells (mucus) Small Intestine = duodenum (first 20cm) & ileum Bile = produced in liver, stored in gall bladder, into duodenum via bile duct. = no enzymes. Bile salts = emulsifying lipids (lowers surface tension = globules – droplets [surface area]) = neutralise acidity = exocrine glands in Pancreas via Pancreatic duct. = Contains enzymes. Trypsinogen – Trypsin (Enterokinase) = Endopeptidases (protein > peptides) Pancreatic Amylase (starch > maltose) Pancreatic Lipase (lipids >fatty acids & glycerol) Pancreatic juice Walls of duodenum = Brunner's Glands (secrete alkaline juice & mucus) – correct pH & lubrication/protection Enzymes secreted by cells at tips of villi (Crypts of Lieberkuhn) Maltase = Maltose > 2 Glucose Sucrase = sucrose > glucose & galactose Endopeptidases/Exopeptidases = polypeptides > amino acids Endo = quaternary/tertiary – smaller polypeptides. Exo = peptides – amino acids Absorption Ileum adapted†¦ – Long BY2 revision Page 3 – Long Lining folded = large surface area Villi = finger like projections Epithelial cells = surface of villi (microscopic projections – microvilli) Large number of mitochondria = lots of energy required Glucose & Amino-acids = epithelium of villi (diffusion & active transport) into capillary network – hepatic portal vein to liver Fatty acids & Glycerol = lacteal (blindly ending lymph capillary) – lymphatic system into bloodstream (thoracic duct) Fatty acids, Glycerol & most vitamins = diffusion through epithelial cell membrane Glucose, Amino acids & dipeptides = need ATP (energy) – co-transport (Na+ ion) Dipeptides digested intracellularly-pump ions out and then draws more in – carries molecules in with it. Large intestine – Caecum, Appendix, Colon & Rectum – Water & mineral salts absorbed in colon – vitamins secreted by micro-organisms (vitamin K & folic acid (Vitamin B9) – Faeces = semi-solid condition (undigested cellulose, bacteria, sloughed cells) – defaecation Uses†¦ Soluble food products – bloodstream – tissues (assimilation/provide energy) – Glucose = energy release (respiration)/excess stored (fat cells) – Amino Acids = protein-synthesis. Cannot be stored (deaminated – urea {disposed} & carbs {stored}) – Lipids = membranes/hormones/excess stored as fat BY2 revision Page 4 Structure of the gut 24 May 2011 08:52 Peristalsis = aids movement of food through alimentary canal 1) 2) 3) 4) Ingestion Digestion (mechanical = increase surface area/chemical = enzymes, glands in wall/outside wall) Absorption Egestion Structure of Mammalian Gut – Outer serosa = layer of connective tissue (protection/reduces friction from other organs as it moves) – Muscle layer = inner circular/outer longitudinal muscles = peristalsis – Sub-mucosa = connective tissue, contains blood/lymph vessels – absorption & nerves (co-ordinate muscular contractions – peristalsis) – Mucosa = innermost layer (lines wall of gut), secretes mucus (lubrication & protection), secretes digestive juices in some regions (stomach)/absorbs food (ileum) – Lumen = cavity of gut BY2 revision Page 5 Glands 1) Large glands outside gut – secretions pass through tubes/ducts into lumen Eg. Salivary gland, liver, pancreas 2) Glands in form of cells in sub-mucosa Eg. Secrete mucus in duodenum (Brunner's glands – alkaline juices also) 3) Glands in form of cells in mucosa Eg. Gastric glands(stomach) = gastric juice Crypts of lieberkuhn(in base of villus of small intestine) = enzymes (complete digestion) – maltase = maltose – Sucrase = sucrose – Endopeptidase/exopeptidase = peptides/dipeptides BY2 revision Page 6 Adaptions for nutrition 24 May 2011 09:37 Nutrition = obtain energy to maintain life functions and matter to create/maintain structure (from nutrients) Autotrophic plants Use simple organic materials CO2 & H2O to manufacture energy & make complex compounds (make own food) – provide food for others = producers Green plants build up complex organic molecules eg sugars from CO2 & H2O. Source of energy = sunlight (absorbed in chlorophyll & related pigments) [6CO2 +6H2O > C6H12O6 + 6O2] Use energy from special methods of respiration to synthesize organic food Consume complex organic food material (cannot make own food) = consumers. Take food into bodies and break down by digestion. Usually internal in digestive system. Digested material – absorbed (body tissues – used by cells) Herbivores/Carnivores/Detritivores Dead/decaying matter – no specialized digestive system. Secrete enzymes outside body & absorb. (extracellular digestion). Microscopic = decomposers (important recycling valuable nutrients – nitrogen) – Photosynthesis Plants/algae/ certain bacteria Autotrophic bacteria Animals, fungi, some protoctists & bacteria Most animals – Chemosynthesis Heterotrophic – Holozoic feeders – Saprophytes (saprobionts) – Parasites – Mutualism (symbiosis) Fungi & some bacteria Tapeworm Organism that live in/on another organism and receive nutrition from it. Host suffers harm. Highly specialized. Cellulose Involves close association between members of2 different species. digesting bacteria Both derive some benefit from the relationship BY2 revision Page 7 Reproductive Strategies 24 May 2011 10:08 Life cycle = sequence of changes through which it passes during its life from origin in reproduction until death. Reproduction = ability to produce other individuals of the same species Asexual – Rapidly produces large numbers (identical genetic composition = clone) – Binary fission (eg. Unicellular organisms – bacteria/amoeba) – Budding (eg. Hydra/yeast) – Bulbs (eg. Onion/daffodil) – Runners (eg. Strawberry) – Tubers (eg. Potato) Sexual – Involves 2 parents – Less rapid than asexual – Offspring are genetically different – Fusion of haploid gametes Advantages/Disadvantages†¦ Asexual = lack of variety (adapting to environmental change) = if well suited to environment conditions, large numbers of successful type built up quickly Sexual = genetic variety (adapt to environmental change) = development of resistant stage in life cycle (can withstand adverse conditions) = formation of spores, seeds, larvae = dispersal of offspring. Reduces intraspecific competition – enables genetic variety to develop as required. = more chance of mutation (complexity of process) Production of Gametes Diploid = body cells (mitosis) Haploid = sex cells/gametes (meiosis) Haploid Sperm + Haploid Egg = Diploid Fertilized Egg Zygote formed – mitosis to grow Male gamete = small& extremely motile Female gamete = large/sedentary (presence of stored food) Mammalian eggs have only enough to survive until formation of placenta External Fertilization – Discharge gametes directly into sea/freshwater – Considerable wastage = eggs may not encounter sperm – Vast numbers of gametes produced – Frogs – joining of sperm/egg assisted by coupling. Male rubs hind legs on female for her to lay eggs, he immediately releases seminal fluid over them. – Amphibians usually terrestrial, must return to water to breed = external fertilization Internal Fertilization – Occurs inside body of female – Requires intermittent organ to introduce sperm to female's body – Less chance of gametes being wasted BY2 revision Page 8 – Less chance of gametes being wasted Allows male gamete to be independent of water for movement Fertilized egg can be enclosed with protective covering before leaving female. (Animals lay eggs) Embryos develop within parent and derive nourishment from her (placenta) = greatest adaption (mammals) Development of Zygote – Usually outside body – easy prey for predators – Many eggs produced to ensure some survive – Insects, internal fertilization (ensure sperm deposited in female's reproductive tract), external development (laid on food source) – Evolution of amniote egg (reptiles/birds) = fluid filled cavity, surrounded by membrane & protective shell, encloses embryo within yolk sac – Birds incubate eggs = embryo development (external) – Mammals = young retained in mother's womb/uterus (no shell). Embryo nourished from mother's blood supply (placenta). Born in relatively advanced state of development. Parental Care – Very little usually – Stickleback looks after eggs, defends territory, fans eggs to provide o2 until they hatch – Birds & mammals = provision of shelter, feeding, protection from predators, training for adult life. More parental care provided = fewer offspring produced Unisexual/Hermaphrodite â₠¬â€œ Plants = male and female gametes produced in one individual – Every individual capable of forming fertilized eggs – Possibility of self-fertilization = inbreeding (reduced genetic variability) – No intromittent organs – special techniques evolved for transferring gametes Success of Insects – Mainly terrestrial – Depend on these to pollinate crops – Competition for food also – Carry disease eg. Malaria Incomplete Metamorphosis (eg. Grasshopper) – Egg – Intermediate form = nymph (resembles adult – smaller) – Hard exoskeleton – doesn't grow, must shed skin/molt – Does this a series of times until it reaches full size Complete metamorphosis (eg. Butterfly/housefly) – Egg – Lava (specialized for feeding/growing) – Pupa/chrysalis – complete change – Emerges as adult specialized for dispersal and reproduction Plants Simple plants = algae (seaweeds = confined to sea) & mosses & ferns (confined to damp areas -male gamete can swim to egg) Successful plants = conifers & flowering plants (independent of water for reproduction – able to colonize land) Flowering plants = morphology (Efficient water carrying xylem vessels & reproduction) – Male pollen grains with hard coat = withstand desiccation (transfer to stigma of female – affect by environmental conditions) – Plants & grasses = small inconspicuous flowers – pollen carried by wind – Brightly coloured flowers & scent = attraction by insects (carry pollen to stigma) BY2 revision Page 9 – Brightly coloured flowers & scent = attraction by insects (carry pollen to stigma) Male gametes travel through pollen tube to female part and egg (no longer needs film of water to reach egg) Fertilised egg develops into seed containing food store (with resistant coat) Key to success = relationship with animals (attract insects which pollinate/seed dispersal) & enclosure of eggs in ovary and evolution of seed – Can survive adverse conditions Flowering plants are so successful because of†¦ – Short interval between flower production and setting of seed (few weeks) – Seed with food store = embryo develops until leaves are produced above ground (photosynthesis) – Seed protects embryo from desiccation & other hazards = resistant coat – Leaves deciduous & succulent = decay when fall to ground – humus produced. (rapid recycling of ions for reuse) BY2 revision Page 10 Translocation 24 May 2011 14:41 = transport of soluble organic materials, sucro se and amino acids (bi-directional movement) Products of photosynthesis = phloem. From source (area that makes the photosynthate – sucrose = leaves) to sink (where needed for growth/storage) Phloem structure – Sieve tubes (adapted for longitudinal flow of material = no nucleus ,have pores =sieve plates allows rapid flow of manufactured food substances) – Companion cells (linked to sieve tubes by plasmodesmata with fibres & parenchyma, dense cytoplasm = lots of mitochondria – lots of metabolic activity, large nucleus – controls activity) – Phloem fibres – Phloem parenchyma â€Å"Mass flow† hypothesis – There is a passive flow of sucrose from source to sink – Does not account for observations such as movement in opposite directions at same time & rate – Other hypotheses = diffusion, cytoplasmic streaming Evidence for translocation†¦ 1) Aphid (greenfly) – Feed (proboscis), leave embedded proboscis, liquid = sucrose & amino acids. Sectioning stem shows proboscis is in phloem sieve tube 2) Ringing Experiments – Cut off ring of bark (including phloem, leave xylem), immerse in water. Swelling above cut = accumulation of organic solutes, cannot continue. Will eventually die 3) Radioactive isotopes – Carbon-14 supplied to plant – fixed in glucose upon photosynthesis (14C6H12O6) – Stem cut, x-ray = phloem contains radioactivity BY2 revision Page 11

Photography term paper

â€Å"Photography can only represent the present. Once photographed, the subject becomes part of the past† (Abbott, Bernice). Since the beginning of time humans have tried to commemorate their existence and one of the ways we have done so is through photography. Photography can be found anywhere. One of the most common places you can find photography is in a museum; which is where my story begins.As I entered the doors of the Museum of Photography at the University of Riverside I was transported through time. I was taken back to a time when hydrotherapy was nearly a budding phenomenon. A time where the mention of daguerreotype; a picture made on a mirror-like surface, would stop people dead in their tracks. A time where death; as tragic as it was, was celebrated as art. The time of Post-Mortem photography.As I ventured deeper into the world of Post-Mortem photography, I quickly discovered that Post- Mortem photography meant photography of the deceased. I immediately questioned the photographers' motives and was hesitant to except their works as art. However, as I continued to examine and observe I realized that these photographs weren't as horrific as I had made them UT to be. In fact, they were quite beautiful; In that they leave something behind for the living to hold on to.As I continued through the halls of the museum I found several other photographs whose subjects were living. I favored these photographs over the other photographs because they were much more cheerful. Throughout my exploration of the museum In total there were four photographs that stood out to me. Photography term paper By zoologically out to be. In fact, they were quite beautiful; in that they leave something behind for exploration of the museum in total there were four photographs that stood out to me.