Bacteria :: essays research papers

Describe the structure and life processes of bacteria. Bacterial cells, like plant cells, are surrounded by a cell wall. However, bacterial cell walls are made up of polysaccharide chains linked to amino acids, while plant cell walls are made up of cellulose, which contains no amino acids. Many bacteria secrete a slimy capsule around the outside of the cell wall. The capsule provides additional protection for the cell. Many of the bacteria that cause diseases in animals are surrounded by a capsule. The capsule prevents the white blood cells and antibodies from destroying the invading bacterium. Inside the capsule and the cell wall is the cell membrane. In aerobic bacteria, the reactions of cellular respiration take place on fingerlike infoldings of the cell membrane. Ribosomes are scattered throughout the cytoplasm, and the DNA is generally found in the center of the cell. Many bacilli and spirilla have flagella, which are used for locomotion in water. A few types of bacteria that lack flagella move by gliding on a surface. However, the mechanism of this gliding motion is unknown. Most bacteria are aerobic, they require free oxygen to carry on cellular respiration. Some bacteria, called facultatibe anaerobes can live in either the presence or absence of free oxygen. They obtain energy either by aerobic respiration when oxygen is present or by fermentation when oxygen is absent. Still other bacteria cannot live in the presence of oxygen. These are called obligate anaerobes. Such bacteria obtain energy only fermentation. Through fermentation, different groups of bacteria produce a wide variety of organic compounds. Besides ethyl alcohol and lactic acid, bacterial fermentation can produce acetic acid, acetone, butyl alcohol, glycol, butyric acid, propionic acid, and methane, the main component of natural gas. Most bacteria are heterotrophic bacteria are either saprophytes or parasites. Saprophytes feed on the remains of dead plants and animals, and ordinarily do not cause disease. They release digestive enzymes onto t he organic matter. The enzymes breakdown the large food molecules into smaller molecules, which are absorbed by the bacterial cells. Parasites live on or in living organisms, and may cause disease. A few types of bacteria are Autotrophic, they can synthesize the organic nutrients they require from inorganic substances. Autotrophic bacteria are either photosynthetic or Chemosynthetic. The photosynthetic bacteria contain chlorophyll that are different from the plant chlorophyll. In bacterial photosynthesis, hydrogen is obtained by the splitting of compounds other than water.

Identify Risk, Threats, and Vulnerabilities

Some risks that I have identified are social engineering techniques due to the excessive trust given to messages coming from friends, contacts or followed people within the OSN(Online-Social Network) identity theft and information leaking furthermore, spam sending and malware distribution through Social Networks are increasing at an incredible pace. They are not the only threats. Within the World Wide Web, social network is becoming the favorite target for cybercriminals. This Attention requires an intensive focusing of web security efforts and money the most significant threats along with the common vulnerabilities exploited. Sensitive attribute inference through machine learning algorithms it is possible to infer sensitive data from one user. Collecting data from user’s contacts and experimented attacker can predict some not explicit data. For example, if all the friends of one user belong to one political party, it is safe to predict that the user has the same political ten dencies. Excessive exposition of private data inadequate privacy configuration settings may lead to publishing sensitive information. Some of the threats are private data management is a key feature that I have found inside of social networks. Digital dossier building- Everyone can collect published information through different OSN about one user and extract a complete dossier about it, Secondary Data Collection users may grant the platform secondary information (such as IP address, contacts list, messages or visited pages) Re-identification in spite of using fake data to register on a Social Network it is feasible to associate users shared data (such as text, photos, and video’s) with real names or e-mail directions. Vulnerabilities associated with OSN it is difficulty to completely remove all user information when deleting an account. When users try to leave a Social Network, license agreement clauses appear rights that are transferred to the platform when the content is uploaded. Thus if one would like to remove there uploaded material, it would find that the only way to do so is by deleting the videos or photos one by one manually another vulnerability would be weak authentication method on the internet are one of the most important vulnerabilities that web environments have nowadays. The combination of user-name and password is commonly misused by the user who seeks easy-to-remember login details (such as short user-name and passwords, passwords with no combination of numbers and letters same username and password for several domains) another vulnerability is non-validation of users data during registration process. Most of the OSN do not use a validation process during new user’s registration. Unfortunately, just checking a valid email address, the preferred validation requirements, is not an adequate method, which leads to proliferation of fake populating the network. In conclusion On-line social networks represent one of the last and most important internet services most of the enterprises hesitate to integrate OSN into their business model, this new phenomenon cannot be ignored, but neither can be adopted without knowing the risks account when attempting to protect users and systems. I have identified the risk, the threats that compromise them and noted the vulnerabilities exploited by those threats.

Disparate Dwellings in Jane Eyre - Free Essay Example

Sample details Pages: 2 Words: 732 Downloads: 10 Date added: 2019/05/15 Category Literature Essay Level High school Tags: Jane Eyre Essay Did you like this example? In Charlotte Bronts Jane Eyre, each distinct place where Jane stays represents a different point in her life, and they each have an impact on her as a whole. In the novel, both Gateshead and Lowood Institution have a great effect on Jane, but a reader might wonder which place is she better off at? Jane Eyre is much better off at Lowood than she was at Gateshead Hall. She is not continually physically abused at Lowood Institution, as she is at Gateshead. Don’t waste time! Our writers will create an original "Disparate Dwellings in Jane Eyre" essay for you Create order Jane is allowed to have friends and to confide in people whom she loves and trusts. At Lowood, she is able to obtain partial freedom within her education, which later leads her job as a governess. Even though both residences have their own significance for Jane, she has a better life at Lowood Institution. As Jane grows up, she stays with her Aunt Reed at Gateshead Hall, where she is subject to multiple accounts of abuse. While a child grows up, it is crucial that they are nurtured and loved so that they become respectable people later in life. Jane, however, never experiences a familial love and, therefore, feels a sense of isolation her entire time at Gateshead. Instead of experiencing this love, she becomes used to physical and verbal abuse equating time with family. Accustomed to John Reeds abuse, I never had an idea of replying to it; my care was how to endure the blow which would certainly follow the insult (Bront 9). The words never and certainly imply that this abuse has happened multiple times with no consequence for John. At Lowood, she is punished for things that she has done, not made up scenarios in which Jane is always at fault. When Jane first arrives at Lowood, she still feels a small sense of isolation, but that is short-lived. She soon meets Helen Burns, who is an unbelievable influence on Jane. Lowood Institution allows Jane to gain friendships and to open up to people about her past experiences. Meeting different people at Lowood has a huge impact on Janes life. If all the world hated you, and believed you wicked, while your own conscience approved you, and absolved you from guilt, you would not be without friends (Bront 79). Helen helps Jane realize that shes not an awful, unhappy person just because people have told her so her entire life. She is whoever she sets out to be. Jane has friends who are there for her and will stick by her side no matter what. She not only gains support, but also advice that she carries with her throughout the rest of her life. In Janes life, the decision to leave Lowood in search of a new servitude becomes imperative in constructing her future. She is allowed partial freedom and obtains an education which later on allows her to get a job and meet her future husband. Her education is well-earned and benefits her immensely. But Servitude! That must be a matter of fact. Anyone may serve: I have served here for eight years Can I not get so much of my own will? Is not the thing feasible? Yesâ€Å"yesâ€Å"the end is not so difficult (Bront 100). The discipline and schooling at Lowood makes it easy for Jane to figure out a way to find a new residence for servitude. Jane also knows that she can do something with her life than just feeling isolated and detached. She can find happiness by following her own passions. Even though both Gateshead Hall and Lowood Institutions remain critical points that help to shape Jane Eyres life, she endures much less hardship at Lowood. Mrs. Reed and the Reed children are no longer able to harm or isolate Jane. Lowood allows for Jane to create new friendships in which she can confide in those whom she eventually loves and trusts. She now possesses some semblance of family. Janes partial freedom and education, which she could have only obtained at Lowood, help her to discover new paths in life. All throughout Jane Eyre, Jane suffers at Gateshead but, on the other hand, thrives at Lowood. If she was truly better off at Gateshead, why would Jane be so eager to leave when the concept of schooling was made a concrete possibility? She wishes to escape the oppression she experienced at Gateshead. Works Cited Bront Charlotte. Jane Eyre. EMC/Paradigm Pub., 1998.