Unit 12A: Diseases and Infection Plan
Always refer to the brief to ensure your work meets the assessment criteria.
EVERYTHING YOU RESEARCH NEEDS TO BE REFERENCED
Introduction
Keep it brief and use assignment brief context. Include definitions for infectious and non-infectious
disease, pathogen. Outline what you will do in this assignment i.e. in this assignment I will discuss….
Disease and infection prevention and treatment is an important element of the work of medical
professionals all over the world. Understanding sickness and the origins of diseases and infections
that impact humans is critical. In this section, non-infectious diseases caused by nutritional,
environmental, genetic, and degenerative variables will be briefly discussed, but the main focus will
be on infectious disease causation, transmission, prevention, and treatment. There will be an
opportunity to investigate the many pathogens and diseases that they cause. Disease and infections
can be caused by a variety of pathogens, and the study of disease, often known as epidemiology, is
the study of how these pathogens interact with the environment and the human body. You may
know someone who has a hereditary or degenerative disease, or you may have had contact with
someone who has. This course will allow you to have a better understanding of the causes of certain
disorders as well as potential remedies. You'll learn about the human body's innate defence
mechanisms and how it might develop its own immunity to infectious disease. You'll think about
how infectious diseases flare up from time to time, as well as the challenges of preventing
transmission and treating those who are afflicted. Pandemics are a serious risk now that worldwide
travel is easily available to many individuals, therefore you'll look into the role of organisations in
preventing and treating infectious diseases. Disease, infections, their transmission, and management
are all variables that need to be understood and known. Is a prerequisite for people interested in
pursuing a career in health science or bioscience. This could be in public health, microbiology,
international health, pharmaceuticals, or the food industry, for example. This section will assist you
in obtaining further education so that you can pursue these and other relevant occupations.
Section A – Infectious Diseases
Bacteria contain cytoplasm, ribosomes, and a plasma membrane, just like eukaryotic cells. The
circular DNA of the nucleoid, the lack of membrane-bound organelles, the peptidoglycan cell wall,
and flagella are all characteristics that distinguish a bacterial cell from a eukaryotic cell. They infect
there host by reproduce quickly in there body by giving off many chemicals called toxins, which can
damage tissue and make you sick. The lag phase, the log phase, the stationary phase, and the death
phase are the four stages of bacterial colony growth. The growth of the bacteria however depends on 4
main conditions: Temperature, pH, Oxygen, Nutrients. The increase in temperature/nutrients/oxygen will
increase the enzyme activity which, increases the growth of bacteria (oxygen levels depends on if the
bacteria respires aerobically or anaerobically). Nevertheless, the pH levels can increase the growth of
bacteria, generally the favoured pH is 7.4. Bacteria is the cause of many diseases, one of many which is
called, 'Cholera'. Cholera is an acute diarrheal illness caused by infection of the intestine with Vibrio
cholerae bacteria. The bacteria enters the body through food and water which is contaminated, it then
gives off toxins; this then damages the tissue in the small intestines which causes the body to secrete
enormous amounts of water, leading to diarrhea and a rapid loss of fluids and salts.
Viruses are non-living infectious agents, which are made up of a short section of RNA surrounded by
protein. Viruses unlike normal cells and some bacteria, don’t have a nucleus. They infect cells by inserting
, their own RNA into the DNA of the cell and then make the cell produce more copies of the virus (lysis
occurrence). Viruses affect all varieties of organisms, including bacteria, which are called
bacteriophages. The lifecycle of a virus is no different form a pathogen, they cannot divide or reproduce
but complete the lytic pathway. Common diseases caused by viruses is the: common cold, HIV, Ebola,
Chickenpox and measles. The stages these disease come in place are 6. Attachment, penetration,
uncoating, biosynthesis, assembly, release. To simplify it, attachment is the virus attaching itself o the cell
using it protein, penetration is the virus entering the cell, uncoating is the virus breaking down to release
its RNA, biosynthesis is when the cell replicates the RNA and produces multiple new viral components,
assembly is the replicated parts coming together to the virus and finally release is the cell bursting (lysis)
to release the virus which can carry on these stages and infect nearby cells.
Parasites are living creatures that get nutrition and other resources at the expense of another organism,
known as the host, on which or within which they exist, forming a host-parasite relationship. Their
relationship may be necessary for the parasite to survive (in which they are obligate parasites) or not
(facultative parasites). As previously stated, parasites can reside on the host's surface (ectoparasites) or
within the host's body (endoparasites). Parasites include a wide range of species, including
microorganisms, insects, and worms, etc. For example the tapeworm Taenia solium, after forming a
strong bond with the walls of the small intestine, it is able to absorb nutrients in the digestive tract of its
human or pig host. To assist form and maintain the parasite-host interaction, parasites are frequently
highly specialised to the parasitic lifestyle, such as Taenia. Many parasites have a direct life cycle whereas
others have an indirect life cycle, involving a vector or host. In complex life cycles the parasite's
development and progression through the life cycle is adapted to the physiology and behaviour of the
host.
Protozoa are unicellular eukaryotic microorganisms lacking a cell wall, instead the body is covered by a
pellicle. They are commonly called flagellates; mostly have one membrane-bound nucleus in the cell; the
nucleus has diffused appearance due to scattered chromatin, the vesicular nucleus contains a central
body called endosome or nucleoli in addition, ciliates have micronucleus and macronucleus. Infections
caused by protozoa can be spread by ingestion of cysts (sleeping life stages), sexually transmitted
diseases, or insect-borne organisms (insects that infect the disease by bites or stings). Many of the most
prevalent and deadly human diseases are caused by a protozoan infection, including African sleeping
sickness, amoebic dysentery, and malaria.
A fungus is a type of eukaryotic organism that includes microorganisms like yeasts, molds and
mushroom. Fungi are eukaryotic creatures that are non-vascular, non-motile, and heterotrophic; they
might be filamentous or unicellular; they use spores to replicate and also because they have a lack of
chlorophyll they are unable to perform photosynthesis. They infect there host by replicating fungal cells
which invade tissues and disrupt there function. Then, they use the host to provide them with energy and
nutrients which will help the spread more. Some examples of fungi related diseases are athlete's foot and
ringworm. The life cycle of fungi can vary in different kinds. For most of the molds indoors, fungi are
considered to go through a four-stage life cycle: spore, germ, hypha, mature mycelium.
Questions to research and answer (tick when done):
Bacteria Virus Parasite Protozoa Fungi
What are the main features? ✔ ✔ ✔ ✔ ✔
How can you tell if an organism is one? ✔ ✔ ✔ ✔ ✔
How do they infect organisms? ✔ ✔ ✔ ✔ ✔
What is the lifecycle? ✔ ✔ ✔ ✔ ✔
How does it cause disease? ✔ ✔ ✔ ✔ ✔
