• BIO-112-IT1-S-14 Topic 7 Module 2 Exam - topics for essay and sho...
Viruses.
1. Why are viruses not living organisms? Pg325
Viruses are not considered living organisms because they have a single viral structural. This means viruses are not cells because they have no nucleus, organelle, or cytoplasm, and no genetic material. Having none of these characteristics viruses cannot be considered a living cell because they do not metabolize, respond to stimuli or reproduce on their own. They have to infect a living cell by entering a l host to reproduce more of its self.
2. Label the parts of a typical virus. Know the function of each part.
Pg 324???
3. Give examples of disease causing viruses. P 325
Disease causing viruses have a reservoir where the virus exists and is where most symptoms in host animals are either shown or not. The animal with the reservoir acts as a continual source for the virus for other host species. Some examples of this reservoir virus that causes disease in humans include the avian influenza and West Nile encephalitis which is carried in wild birds. Rodents carry viruses that causes Hantavirus pulmonary syndrome, mosquitoes carry yellow fever and raccoons carry rabies.
4. Describe the general viral replication cycle.p326
The general viral replication is like a car assembly factor it starts with attachments which bind virus cell surface receptor. Then it goes to penetration which is where the viral nucleic acid is released inside the host cell. The next step is synthesis where the host cell manufactures viral nucleic acids and proteins. Next is assembly where new viruses are assembled from newly synthesized coat proteins, enzymes, and nucleic acids. Finally it releases the new viruses from the h...
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Bacterial reproduction occurs asexually whereas most bacteria reproduce by binary fission where a single DNA molecule replicates and both copies attach to the cell membrane where the membrane begins to grow between the two molecules once the bacterium doubles in sides the cell begins to pinch inwards where a cell wall forms between the two molecules dividing the orginal cell into two indentical daughter cells. Since the two daughters cells are identical they are susceptibleto the same type of antibiotics to prevent this from happening the daughter cells incorporate genetic variation a process called recombination which can be accomplish through conjugation, transformation or transduction. They can exchange genes between another bacterium or taking up different DNA most commonly dead bacterial cells from their environment or by be contained by bacteriophages.
The word virus comes from the Latin word, poison. A virus infects a cell and into it, inserts its DNA. The virus then multiplies inside the cell and when enough of the virus has been produced, the newly formed viruses will break out into the body of the host, destroying the cell in the process. Variola major and Variol...
Bloodborne pathogens are viruses that deteriorate cells within the body. A virus is a submicroscopic parasitic organism that feeds on cells. Viruses are dependent on cells for their nutrients so the virus survive and reproduce. Every virus consists of either deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). A virus can contain a strand of one or the other, but not both. This RNA or DNA is contained within a protein shell for protection. A virus is a parasite that is dependent upon cells for metabolic and reproductive requirements. By using the cell the virus makes the host very ill by redirecting cellular activity to make more viruses.
Viruses are the simplest and tiniest of microbes, and are made up of proteins, nucleic acid, and lipids. The nucleic acids contain the genetic code that helps them grow and reproduce, but only once they find their way into a living organism. Viruses themselves are not considered living organisms because they don’t have cells, they don’t metabolize nutrients, produce and excrete wastes, and they can’t move around on their own. The remains of the nucleic acid then forms a covering, called the capsid. Once the capsid gets removed, viruses use the building materials of th...
First, the internalization of the virus was determined. Three stages were identified for the internalization to occur. These stages are as follows: Stage I- actin dependent movement on the cell surface. Stage II- Unidirectional movement toward the nucleus by use of microtubules. At this stage the virus is inside the cell and headed toward the lysosome. Internalization was found to occur at about 190 seconds. Stage III- Bidirectional movement within the cell and is dependent on microtubules as well. It was determined through experimentation that microtubule movement only occurs once internalization of the virus has
Common animals that carry these diseases are rats, prairie dogs, and parrots (“Exotic Animals as Pets”). According to Live Science, a science news website, researchers have found that 13 zoonoses, which are diseases transmitted from animals, cause approximately 2.2 million human deaths per year. "From cyst-causing tapeworms to avian flu, zoonoses present a major threat to human and animal health," lead researcher Delia Grace, a veterinary epidemiologist. According to researchers, about 60% of all human diseases are zoonotic, meaning they come from animals. Most zoonotic human diseases come from livestock, such as pigs, chickens, cattle, goats, sheep, and camels (Bryner). If humans would not come into close contacts with animals there would not be as many diseases in the world which would result in less human and animal deaths. According to WebMD, an American corporation that provides health news, advice, and expertise, a very common zoonotic disease in the world today is influenza, also known as the flu. Influenza usually comes from ducks, geese, or pigs and then it spreads to chicken and pigs. Leptospirosis is another example of a human infection that comes from animals. Leptospirosis is caused by contact with water, food, or soil that has been contaminated with urine from infected animals. This infection can lead to liver failure, kidney damage, brain and spinal cord infection, and rarely, death
The flu, is characterized as an infection of the respiratory tract caused by influenza viruses. Influenza infection is commonly ranked as one of the most dangerous diseases on Earth because it affects all age groups and can re-occur in any individual. Influenza A, B and C viruses belong to the orthomyxovirus, which is the family of enveloped viruses with segmented, single-stranded, negative-sense RNA genome (Calder et al., 2010; Cox & Subbarao, 1999). Type C cause sporadic mild influenza-like illness in children. Type B are known to cause recurring regional and local epidemic disease, but it is only found in human. Type A virus is the most
Microbes are microscopic life forms, usually too small to be seen by the naked eye. Although many microbes are single-celled, there are also numerous multi-cellular organisms. The human body has 10-100 trillion microbes living on it, making it one giant super-organism. Since the first link between microbes and diseases was made, people have been advised to wash their hands. Scientists, however, have recently started to investigate more closely how the microbes that call the human body home affect our health. While some microbes cause disease, others are more beneficial, working with our bodies in many subtle ways.
Before, bacteria were known that it is fully cloned from the parent cell so bacteria were not suitable for genetic study. However, Lederberg and Tatum claimed DNA transfers occur in bacteria via mechanism of sex. The two possible models that Lederberg and Tatum (1946) considered for mating process in Escherichia coli (E.coli) are conjugation and transduction process.
Any bacteria that survives an antibiotic attack will, like a human to a virus, develop an immunity to said chemical and be able to fight it off rather effortlessly if it is attacked again. While this survival is rare, bacteria possess an ability no other organism is capable of; the transfer of DNA. An immune bacteria can share its immunity with dead bacterium, even bringing them back to life. These specimens are called
First and foremost, a virus is defined as a particle composed of protein, nucleic acid, and sometimes, lipids, which can reproduce itself only by infecting live cells. The reason why viruses are questioned if they are living or nonliving is if they exhibit all the characteristics of life. One of the questionable characteristics regarding a virus is reproduction. Living organisms have the capability to reproduce on their own, sexually or assexually. However, viruses reproduce by infecting living cells, therefore being dependant on something. Another reason of why viruses are questioned as living or nonliving is their genetic code. Even though they have DNA and RNA inside a protein coat, they don't have a nucleus or ribosomes to copy their genes,
Viruses are important to discuss because they are analyzed in almost all microbiology classes. Viruses can be characterized as, “any of a group of submicroscopic entities consisting of a single nucleic acid chain surrounded by a protein coat and capable of replication only within the cells of living organisms” (Biology). Bacteriophage are more specific in a sense that they are “a virus that infects and replicates within a bacterium” not just any living organisms cells (Biology). These viruses can replicate in 2 different cycles: lytic cycle or the lysogenic cycle. If a virus takes enters the lytic cycle it will cause infection and destruction of the host cell. This is done when the virus first penetrates the cell membrane of the host cell.
Bacteria are single celled microbes. Bacteria reproduce by binary fission. In this process, the bacterium, which is a single cell, divides into two identical daughter cells. Binary
Prokaryotes are divided into eubacteria and archaebacteria. Eubacteria are considered bacteria, and will be henceforth referred to as such. Archaebacteria lived in more extreme environments, are older than eubacteria, and have sufficient chemical differences to be distinct from bacteria. Prokaryotes are unicellular organisms that reproduce through fission and conjugation, have great metabolic diversity, have a single chromosome arranged in a circle called a plasmid with no nuclear membrane, and tend to have cell walls. One of the most notable characteristics is the lack of membrane-bound organelles, such as lysosomes or the endoplasmic reticulum. Bacteria have three types of shapes: coccus, bacillus, and spirillum (Starr, C., et al, 2004). Cocci are sphere-like and are around .5 to 1 µm long, bacilli are rod-like and 0.5-1.0 µm wide by 1.0-4.0 µm long, and spirilli are spiral-shaped and vary from 1 µm to over 100 µm in length (Elert, G, 2006.) Designations of this type may be made more precise through addition of morphemes to the front of the word, such as in the case of diplococcus, which means a pair of spherical bacteria. Gram-negative bacteria have an additional coating beyond the cell wall, called a capsule. These capsules have lipopolysaccharide in them, which is toxic and caus...
\In-fact, mutations and genetic changes result in defence mechanisms against antimicrobials, where the majority of these changes are a direct result of selection pressure on bacteria to develop resistance.[25, 26] In addition, bacteria may obtain these genes through the process of conjugation where bacteria trade plasmids which contain resistant genes. Plasmids are an extra chromosome element of DNA which are found in the cytoplasm of a bacterium, as illustrated in Figure 2.[25] The process of conjugation is also referred to as horizontal gene transfer.[26]
The word virus is derived from the Latin word meaning “poison, slimy liquid, or poison juice. ” Viruses are very small infectious (pathogenic) particles that cannot be seen with an ordinary lighted microscope. The virus is encapsulated with protein, and is unable to multiply unless it is living inside the cells of a living host. As such, when a virus enters the living cells of an animal or plant, something extraordinary