Most Bacteria Can Consume Things Biology Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

A typical bacterium has a rigid cell wall and a thin, rubbery cell membrane surrounding the fluid, or cytoplasm inside the cell. A bacterium contains all of the genetic information needed to make copies of itself, its DNA in a structure called a chromosome. In addition, it may have extra loose bits of DNA called plasmids floating in the cytoplasm. Bacteria also have ribosome's tools necessary for copying DNA so bacteria can reproduce. Some have threadlike structures called flagella that they use to move.

Most Bacteria can consume things that are already dead. They decompose stuff like shed skin, carcasses, and plant bits such as leaves. These do it by secreting digesting enzymes outside themselves onto the food source. The bacteria then absorb just what they need. Other bacteria can photosynthesize. These include the cyanobacteria that produce oxygen for our atmosphere. Then there are the purple non-sulfur bacteria that do both, photosynthesize and get their energy from organic compounds. Some symbiotic bacteria help us digest the food we consume. These beneficial gut flora provide us with essential nutrients like vitamin B1 & B6 which we cannot make ourselves. Bacteria can clone themselves; this is the way in which they reproduce. Bacteria reproduces asexually and this is referred as Binary Fission; this is when one well splits (fission) to yield two (binary) cells.

4. The structure of Viruses

The nucleic acid of a virion is enclosed within a protein coat, or capsid, composed of multiple copies of one protein or a few different proteins, each of which is encoded by a single viral gene. Because of this structure, a virus is able to encode all the information for making a relatively large capsid in a small number of genes. This efficient use of genetic information is important, since only a limited amount of RNA or DNA, and therefore a limited number of genes, can fit into a virion capsid. A capsid plus the enclosed nucleic acid is called a nucleocapsid.

5. The characteristics of Viruses

A virus is very different compared to bacteria's and fungi's; it's essentially a delivery mechanism for a bit of DNA or RNA. They're very, very small; some can only be seen under very powerful electron micrographs. They can't reproduce on their own. But they attach to one of your cells, and by using those strands of DNA or RNA, they reprogram these cells to make new copies of themselves and this directly disrupts the cell's usual function, and eventually kills it.

8. The structure of Fungi

Fungi's are eukaryotic microbes. A eukaryotic microbe consists of a central nucleus and they are more complex and much larger than prokaryotes. Funguses are composed of fragments of nucleic acid which is surrounded by protein coats. Fungi's have three basic forms; mold, mushrooms and yeast: although some fungi may consist of both forms. Molds are structured by filamentous hyphae. A yeast cell consists of a round or oval cells, they are generally not consisted with a hyphae and they are not presented with a furry appearance. Hyphae's are filaments of living substances. They are consisted of a nuclei and cytoplasm and a cell wall which is then composed of a chitin or cellulose. Funguses can be sexual or asexual reproduction. Budding is consisted to be asexual and spores are known to be sexual reproduction.

9. The characteristics of Funguses

There are two kinds of fungus: real fungus and fungoids. Fungoids are organisms that lead a similar life to that of fungus. Real fungi are more similar to animals than to plants. They eat, they don't photosynthesize like plants. They can be a single cell like yeasts or have many cells like mushrooms. Funguses are the first to colonize a new territory and they prepare the soil for plants. They also reduce or decompose dead organic matter. Some are parasites and cause and some are simbionts (lichens are formed by the interaction of a fungus and algae), and some live freely, Fungi's are also specific in their action; they always infect a particular organ or organism.

Task 2 (M1)

1) HIV

HIV (Human immunodeficiency virus) is a lentivirus (which is a member of the retrovirus family) that can lead to AIDS (acquired immunodeficiency syndrome), a condition in humans in which the immune system begins to fail, leading to life-threatening opportunistic infections.

HIV's source of infection is by venereal spread. This is spread from body fluids through sexual intercourse. Fortunately, the viruses do not survive in air and are quickly killed by hot water and detergent. They can only be passed from person to person by direct contact between body fluids, mainly blood. The most common ways in which transmission occurs are: during unprotected (without using condoms) homosexual or heterosexual intercourse. HIV can also be transmitted to one and another by using a needle for intravenous injection which has been used by an infected person. It can also be passed on by receiving contaminated blood products, for example in the treatment for haemophilia or during a blood transfusion. A fetus may be infected by its mother, as the viruses can pass across the placenta. A baby can also be infected during the process of birth or by its mother's milk.

When the virus enters the human body it parasitizes very important cells of the immune system called helper T cells. The helper T cells not only assist the killer T cells to destroy viruses and cancers, but they also help some B cells to produce antibodies. The immune system is severely disrupted if the HIV

becomes active and harms the effectiveness of their host cells. The main symptoms of full-blown AIDS include the development of other diseases to which healthy people would quickly develop immunity.

2) Candida Albicans:

Candida albicans is a yeast-like fungus that commonly causes infections. Candida albicans lives in the mucous membranes of the mouth, vaginal tract, and the intestines. Certain conditions such as pregnancy, oral contraception, antibiotic use, or a compromised immune system can cause an overgrowth of Candida making it an infection.

The human body contains a vast number of different micro-organisms, including fungi, both on the inside and on the outside. Some of these micro-organisms are beneficial. Others have no effect until either there is a change in their nature or there is a decrease in the body's resistance to them. This allows one type to grow excessively and leads to an infection - a fungal infection of the skin. In principle, Candida albicans can infect all areas of the skin as well as the mucous membranes but it prefers warm moist places.

Infections by Candida albicans, especially the variants that are found in the mucous membranes or the genitals, are contagious. They can be spread from person to person by direct contact, by sexual contact and indirectly by damp towels or flannels.

Nevertheless, Candida albicans are capable of reproducing by oral thrush which appears in the mouth. This is when it is consisted of yellow like spots.

When Candida albican enter the human body it becomes aggressive and begins to invade the circulatory system from where they can easily target different parts of the body. However, Candida albicans mostly multiplies in the hot and humid condition and therefore the parts of the body which remain damp are more prone to get affected by its complication. Candida albicans are also capable of giving out various types of toxins when they aim any organ exacerbating the condition.

3) Streptococcus

This is a type of genus of a non-motile, non-spore-forming, aerobic to facultatively anaerobic bacteria which contains gram-positive, spheric or ovoid cells that occur in pairs or in short or long chains. Dextrorotatory lactic acid id the main product of carbohydrate fermentation. These organisms occur regurlarly in the mouth and intestines of humans and other animals, in dairy and other food products, and in fermenting plant juices. Some species are pathogenic. The type species is streptococcus pyogenes.

The sources of infection in this type of bacteria exists around in salivary spread (oral secretions), it can be spread by person-to-person contact or by exposure to sneezing and coughing. Holding hands can transmit it if the infected person has coughed or sneezed on his hand or wiped his mouth. Sharing food, drinks and utensils can spread it. It's on toothbrushes. Just having someone talk at you is not likely to do it as it requires more than casual contact of this sort. Kissing can sometimes cause it but is less of an issue. This bacterium is located in the upper respiratory mucus. Oral contact with someone infected by streptococcus is highly contagious because the fine mist caused by the bacteria is enough to spread the bacteria.

4) Malaria

Malaria is caused by a single-celled organism, a protoctistan parasite of the genus Plasmodium. Malaria is spread by vector-borne disease, this means when they enter through blood sucking or through ingesting the faeces of the vector. This can then spread from human to human by blood contact (body fluids). the mosquito acts as a vector, by transmitting the parasite from one person to another.

When a bite is introduced into the blood by a female mosquito bite, the parasites multiply inside the liver cells before emerging to invade and multiply inside the erythrocytes (red blood cells). From then on, the parasites emerge from the erythrocytes, releasing toxins in the blood, and it invades more erythrocytes at regular intervals. The length of the cycles varies with the species of Plasmodium. Every time the toxins are released, the immune reactions of the body which destroy them are accompanied by severe fevers. These fevers with their bouts of chills and sweats can decrease in severity if the body slowly becomes immune to the toxins, and many people can carry malaria.

5) Salmonella

Salmonella is a type of bacteria. It is usually found in poultry, eggs, unprocessed milk and in meat and water. It may also be carried by pets like turtles and birds. Salmonella is a genus of rod-shaped Gram-negative enterobacteria that causes typhoid fever, paratyphoid and food borne illness. Salmonella does not ferment lactose. It is motile in nature and produces hydrogen sulphide.

Food borne illness or food poisoning is caused by consuming food contaminated with pathogenic bacteria, toxins, viruses, prions or parasites. Such contamination usually arises from improper handling, preparation or storage of food. Food borne illness can also be caused by adding pesticides or medicines to food, or consuming or by accidentally consuming naturally poisonous substances like poisonous mushrooms or reef fish. Contact between food and pests, especially flies, rodents and cockroaches, is a further cause of contamination of food

S. typhi is a serovar of Salmonella. It causes the disease typhoid fever. The organism can be transmitted by the faecal-oral route -- it is excreted by humans in faeces and may be transmitted by contaminated water, food, or by person to person contact (with inadequate attention to personal hygiene).

The brain senses that there is a bacterial entry of streptococcus in your body. It then sends its own bacteria to fight it via blood stream, but a lot of the time it does not possess the proper bacteria and the body is invaded and overtaken by the new bacteria which then allows it to travel through the bloodstream soon affecting all parts of the body.

6) Human Pappiloma Virus

HPV is one of the most common sexually transmitted diseases. If a man or women are sexually active, it is likely they will acquire with HPV at some point in their lives. There are over 100 types of HPV but only 13 of them are known to cause cancer. The others are harmless or cause genital warts.

HPV can cause cervical cancer; this is a cancer of the cervix - which is the entrance to the womb. HPV infects the cells of the surface of the cervix where it can stay for many years without you knowing. The HPV virus can damage these cells leading to changes in their appearance. Over time, these changes can develop into cervical cancer.

In most cases Genital warts are transmitted through anal, genital or oral sex with a person infected with HPV. A person who's had sexual contact with an infected person can develop a genital wart about three months after initial contact. Poor hygiene can also be a factor in developing genital warts. Also, unprotected sex with a number of partners.

Task 3 (D1)

Gram-positive bacteria are classified as bacteria that retain a crystal violet dye during the Gram stain process. Gram-positive bacteria will appear blue or violet under a microscope, whereas Gram-negative bacteria will appear red or pink. The difference in classification is largely based on a difference in the bacteria's cell wall structure.

The following characteristics are generally present in a Gram-positive bacterium: a very thick cell wall (peptidoglycan). If a flagellum is present, it contains two rings for support. Teichoic acids are present, which serve to act as chelating agents, and also for certain types of adherence

Many species of Gram-negative bacteria are pathogenic, meaning they can cause disease in a host organism. This pathogenic ability is usually associated with certain components of Gram-negative cell walls.

The following characteristics are displayed by Gram-negative bacteria: the cell walls only contain a few layers of peptidoglycan. Cells are surrounded by an outer membrane of lipopolysaccharide outside the peptidoglycan layer. Porins exist in the outer membrane, which act like pores for particular molecules. There is a space between the layers of peptidoglycan and the secondary cell membrane called the periplasmic space. The S-layer is directly attached to the outer membrane, rather than the peptidoglycan. If present, flagella have four supporting rings instead of two. Lipoproteins are attached to the polysaccharide backbone whereas in Gram-positive bacteria no lipoproteins are present

In out experiment for antiseptic techniques we used Bacillus Subtilus and Escherichia coli. Escherichia coli is a gram negative bacterium, they mostly found in the lower intestine of warm blooded animals. Bacillus subtilus is a gram positive bacterium which is commonly found in soil.

To conclude, E.coli was killed off by bleach because e.coli contains a subtance which can be killed off by bleach. Bacillus Subtilis was affected by the fairy liquid because fairy liquid contains a strong substance which defeats the elements that bacillus subtilius contains.