Content Curator
Pathogens and parasites are microorganisms that can impair the health of any living being. The main distinction between pathogen and parasite is that a pathogen defines a microorganism's influence on another living entity, which is generally detrimental, but a parasite explains a microorganism's manner of living, which may or may not be harmful.
| Table of Content |
Key Takeaways: Organism, protozoans, bacteria, eukaryotes, AIDS, mitochondria, virus, fungus.
Pathogen
[Click Here for Sample Questions]
Pathogens are organisms that cause disease. Their host becomes ill as a result of their presence. Viruses, bacteria, fungi, protists, and parasites are examples. An animal, a plant, or a microorganism could be the host organism. Bacteria can be as small as 10 micrometers in size and cause diseases such as typhoid, gonorrhoea, cholera, and food poisoning.
Pathogenic Diseases
Viruses and other pathogens are smaller than bacteria. Viruses can only replicate and multiply within their host cell. HPV (warts), influenza, yellow fever, Herpes 1 and 2, common cold, Rubella, Dengue fever, and AIDS are all diseases caused by viruses. Fungi, which are also eukaryotic organisms, are another form of the pathogen. Aspergillosis, Blastomycosis, Candidiasis, jock itch, and athlete's foot are all fungal illnesses.
Read More:
Types of Pathogens
[Click Here for Sample Questions]
There are six types of pathogens:
Viruses: These are microscopic infection-causing pathogens that multiply only within the host's cells. It is made up of DNA and RNA genomes that are housed inside a protein shell called a capsid. Viruses may infect a wide range of living things, from plants to animals to microbes. In humans, animals, and plants, these can cause mild to severe illness.
Types of Virus
Bacteria: Bacteria are single-celled organisms (prokaryotes) that can thrive in a variety of environments. They are only a few micrometers long and come in a variety of shapes, including rods, spirals, and spheres. Fever, chills, pulmonary inflammation, shortness of breath, and cough are all bacteria-related illnesses.
Bacteria Types
Read More:
Fungi: Yeast, mold, and mushroom are examples of fungi pathogens. These parasitic organisms can be single-celled or multi-celled.
Fungi
Read More: Economic importance of Fungi
Protozoa: Protozoa are single-celled, microscopic organisms that create poisons that cause sickness. Malaria is one of the diseases caused by protozoans.
Read More: Catabolism and Anabolism
Helminth: Helminths are parasitic worms that may be seen with the naked eye. To obtain energy, nutrients, and protection, these parasites feed on a living host, causing sickness, weariness, and disease in the host. Tapeworm is a good example.
Tapeworm
Rickettsia: Rickettsia is a bacteria-like pathogen that thrives inside living cells. Typhus is a good example.
Read More:
Parasite
[Click Here for Sample Questions]
Parasite is an organism that lives inside or on another organism known as the host and profits from the host's suffering. Parasites are organisms that can be seen with the naked eye in their ideal state. As a result, parasites are macro-organisms. Protozoans and helminths are two examples. Parasites are also host-specific. As a result, they can make certain organisms unwell.
Lice is a Parasite Found in Human hair
A total of 36,400 protozoan species have been identified as parasites in other living beings. In humans, however, over seventy protozoan species and 300 helminth species have been identified as parasites. Ninety species are responsible for human illness among them. As a result, it can be concluded that not all parasites are responsible for human disease. Plasmodium is an example of a protozoan, which is a parasite that is known to infect people.
Plasmodium
In disease-endemic locations, parasites use a variety of transmission methods, many of which include intricate interrelationships between the host, parasite, vector, and environmental factors.
Read More:
Types of Parasites
[Click Here for Sample Questions]
Parasites can be divided into three groups.
Protozoa: Protozoans are eukaryotes with only one cell. Protozoa are ubiquitous, meaning they can be found in almost any environment. Within the host, a protozoon grows or divides. Ciliates, Flagellates, Sporozoans, and Sarcodines are some of the protozoa types.
Protozoans
Helminths: Roundworms, tapeworms, pinworms, trichina spiralis, and fluke are examples of parasitic worms. These are large macro-parasites that feed on a living host organism for nutrients, energy, and protection, causing the host to have poor nutrient absorption, sickness, fatigue, and disease. Intestinal worms are visible in the small intestine.
Helminthes Classification
Read more: Phylum Protochordata
Ectoparasites: These parasites are parasites that reside on the outside of the host organism. Lice and fleas are two ectoparasites.
Types of Ectoparasites
Read More:
Difference Between Pathogens and Parasites
[Click Here for Sample Questions]
The key differences between Pathogens and Parasites are tabulated below.
| Pathogens | Parasites |
|---|---|
| Pathogens are organisms that cause disease. Their host becomes ill as a result of their presence. | Parasite is an organism that lives inside or on another organism known as the host and profits from the host's suffering. |
| When pathogens enter their host body, it causes diseases. | When Parasites enter the host’s body, it causes slow reactions such as rashes and slowly degrades the host’s body. |
| Pathogens do not require a host in their lifecycle. | Parasites require a host in their lifecycle. |
| Examples of Pathogens are Viruses, bacteria, fungi and protists. | Examples of parasites are Protozoans, Ectoparasites and helminths |
Some of the diseases caused by pathogens are:
| Some of the diseases caused by parasites are:
|
| Eukaryotic organisms include pathogens. In contrast to prokaryotes, eukaryotes have cells with nuclei and membranes. | Prokaryotic organisms account for the majority of parasites. A prokaryote is a single-celled organism without a nucleus or mitochondria that are attached to the cell membrane. Fungi and parasites are the only exceptions. |
Read More:
Things to Remember
[Click Here for Sample Questions]
- A parasite is an organism that lives inside or on another organism known as the host and profits from the host's suffering.
- Parasites are organisms that can be seen with the naked eye in their ideal state. As a result, parasites are macroorganisms. Protozoans and helminths are two examples.
- Pathogens are organisms that cause disease. Their host becomes ill as a result of their presence.
- Viruses, bacteria, fungi, prions, and parasites are examples.
- Helminths are parasitic worms that may be seen with the naked eye.
Read More:
Sample Questions
Ques. What is the definition of a parasitoid? (2 marks)
Ans: In evolutionary ecology, a parasitoid is an organism that survives close to its host at the expense of the host, eventually killing it. Parasitoidism is one of six key evolutionary strategies within parasitism, and it is differentiated by the host's fatal prognosis, which puts it near to predation. From living inside the host (endoparasitism), allowing it to continue growing before emerging as an adult, to paralyzing the host and living outside it, parasitoids use a variety of techniques (ectoparasitism).
Ques. What is brood parasitism? (2 marks)
Ans: The hosts behave as parents in brood parasitism, raising the young as if they were their own. Cowbirds, whydahs, cuckoos, and black-headed ducks are examples of brood parasitic birds from several families. They don't make their nests, instead laying their eggs in the nests of other animals. Some brood parasite eggs look like those of their hosts, while others have tough shells that make them difficult for the hosts to pierce, signaling that the hosts have chosen to avoid parasitic eggs.
Ques. Mosquitoes are parasites, right? Why? (2 marks)
Ans: In medical terms, a parasite is a creature that lives on or in a host and feeds on or at the expense of that host. In biological terms, it's an organism that benefits from a parasitic relationship, which is a non-mutual interaction in which one species benefits at the expense of the other. To be a parasite by biological/ecological definition, the mosquito must cause harm to its host to benefit itself.
Ques. The female anopheles’ mosquito is a vector, not a parasite, so why is she a vector? (3 marks)
Ans: Because it does not bite humans for its food, female anopheles is not a parasite. Mosquitoes feed on plant nectar, fruit juices, and liquids that exude from plants, both male and female. Female anopheles bites a human to obtain a blood meal to feed her fertile eggs. Their eggs require a certain amount of iron. As a result, they require human blood to reproduce. Their duration in/on the body surface is also insufficient to classify them as parasites. They also perform the function of a vector.
Ques. In plants, what are some instances of saprophytic and parasitic nutrition? (2 marks)
Ans: Plants in the parasitic mode of nutrition rely on the nutrition of other live plants. These plants are known as parasites, and the plant on which they rely for nutrition is known as a host plant. One example of a parasitic plant is Cuscuta.
Saprophytes are plants that get their nutrition from dead and decaying organic materials. This is a type of digestion that occurs outside of the cell. Fungi is an excellent example of this.
Ques. What exactly are prions? (2 marks)
Ans: Prions are transmissible misfolded proteins that can affect the improper folding of regular proteins in the brain. They don't have any DNA or RNA, and the only way they can replicate is to convert already-existing normal proteins to a misfolded condition. These improperly folded proteins are seen in numerous neurodegenerative illnesses, where they accumulate in the central nervous system and form plaques that cause tissue damage.
Ques. What does it mean when something is pathogenic? (2 marks)
Ans: Pathogenicity refers to a pathogen's ability to cause disease. In terms of meaning, pathogenicity and virulence are similar, but some authorities have distinguished pathogenicity as a qualitative term versus virulence as a quantitative term. According to this standard, an organism can be pathogenic or non-pathogenic in a given situation, but not "more pathogenic."
Ques. What is known as antigenic escape? (2 marks)
Ans: When a host's immune system, particularly a human's, is unable to respond to an infectious agent, such as a virus, antigenic escape, immune escape, immune evasion, or escape mutation occurs. This can happen in a variety of genetic and environmental settings. Homologous recombination, as well as immune response manipulation and resistance, are examples of such systems.
Ques. What exactly is malaria? (3 marks)
Ans: Malaria is an infectious disease spread by mosquitoes that affect humans and other animals. Malaria is characterized by symptoms such as fever, exhaustion, vomiting, and headaches. It can cause yellow skin, seizures, coma, or death in severe cases. After being bitten by an infected mosquito, symptoms usually appear ten to fifteen days later. People may get recurrences of the condition months later if they are not appropriately managed. Reinfection usually causes lesser symptoms in persons who have recently survived an infection. If the person is not exposed to malaria for months or years, the partial resistance disappears.
Ques. What is an autoimmune disease? (2 marks)
Ans: An autoimmune disease is a condition that develops when the immune system reacts abnormally to a healthy bodily part. A total of 80 different types of autoimmune diseases exist. Almost any portion of the body can be affected. Low-grade fever and exhaustion are common symptoms. Symptoms often come and go.
Read also:
Comments