U1.3 - Intro to Para (Effects, Evasion, Taxonomy) Flashcards
6 effects of parasite to host
- may infect humans bud do not cause disease
- can cause injury
- can cause invasion and tissue destruction
- can deprive certain nutrients from hosts
- tissue damage
- tissue changes
streamlining
How do parasites cause injury?
- Creation of enzymes
- Invasion and destruction of host tissue
- Depriving the host of essential nutrients and substances
4 types of tissue changes
- hyperplasia
- hypertrophy
- metaplasia
- neoplasia
type of tissue damage:
increase in number of cells
hyperplasia
type of tissue damage:
increase in size of cells
hypertrophy
type of tissue damage:
change from one cell type to another
metaplasia
type of tissue damage:
formation of tumors or neoplasms
neoplasia
inability of parasite to synthesize certain cellular components, so they need the help of the host to obtain these components
streamlining
6 effects of host to parasite
- genetic makeup of host
- nutrition and diet
- natural physical barriers
- chemical components of body fluids
- physiologic function of the body
- immunity and immune response
confers resistance to Plasmodium vivax and Plasmodium knowlesi
Duffy Blood Group Fy (a-b-)
confers resistance to Plasmodium falciparum
sickle cell anemia
macro that inhibits growth of protozoans
high protein diet
macro that favors development and appearance of symptoms and complications of amebiasis
low protein diet
macro that favors development of some tapeworms
high carbohydrates
physical barrier that provides surface protection against invasion from parasites
skin
physical barrier that provide external barriers to parasite entry
mucous membranes
physical barrier between epithelial cells, prevent passage of small molecules
tight junctions
physical barrier that present a hostile environment to microorganisms
low pH of vaginal secretions and gastric juices
lipase content of breast milk is toxic to?
Giardia
What protein in tears and saliva is able to destroy microorganisms?
lysozyme (with the IgA content)
physiologic function: motion of the cilia in the digestive tract that helps in expelling parasites
peristalsis
physiologic function: enables expectoration of certain parasites
coughing
causes parasite to develop evasion mechanisms
immunity and immune response
Parasites eventually become __________ to the immune response.
resistant
T/F:
Absolute immunity frequently happens.
False;
rarely
T/F:
Hosts can also recognize the invading parasite through its pathogen-associated molecular patterns.
True
T/F:
Hosts can also recognize through toll-like receptors.
True
5 parasite evasion mechanisms
- resistance to immune response
- immune suppression
- antigenic variation
- host mimicry
- intracellular sequestration
identify the evasion mechanism:
parasite changes its surface proteins or glycoproteins to avoid detection by the immune system
antigenic variation
identify the evasion mechanism:
parasite can copy certain proteins/ antigens in the body
host mimicry
identify the evasion mechanism:
parasites hide inside the cel
intracellular sequestration
3 kingdoms
- kingdom protista (protozoans)
- kingdom fungi
- kingdom animalia
3 phylums of kingdom protista
- Phylum Sarcomastigophora
- Phylum Ciliophora
- Phylum Apicomplexa
Subphylums and species under Phylum Sarcomastigophora
o Subphylum Sarcodina:
—–ameba
o Subphylum Mastigophora:
—–flagellates (atrial flagellates and hemoflagellates)
Species under Phylum Ciliophora
ciliates
Subphylums and species under Phylum Apicomplexa
Plasmodium, Babesia, Intestinal Coccidians, Tissue
Coccidians
Phylum and species in kingdom fungi
Phylum Microsporidia
* Intracellular parasites
* Now classified as fungi in Mycology
* Spore forming
* Possesses a polar tube (used to penetrate the host cell)
* Ex: Enterocytozoon and Encephalitozoon
Phylums and classes in kingdom animalia
- Phylum Aschelminthes
o Class Nematoda (roundworms) - Phylum Platyhelminthes (flat worms)
o Class Trematoda (flukes)
▪ Order Digenea
o Class Cestoda (tapeworms)
Possible outcomes of parasite to host interactions
- Parasite fails to become established in the host.
- Parasite becomes established and the host eliminates the infection.
- Parasite becomes established, and the host begins to overcome the infection but is not totally successful.
- Parasite becomes established and the host, in trying to eliminate the organism, becomes damaged itself.
- Parasite becomes established and kills the host.
1st line of defense against pathogens
physical barriers
4 physical barriers
- Skin
- Mucous membranes
- Components of body fluids
- Physiologic functions of the body
type of immune response:
body detects and eliminates pathogens through non-
specific mechanisms
Innate immune response
Identify the type of immune response:
Phagocytosis by macrophage and dendritic cells
Innate immune response
type of immune response:
host exposed to the parasite antigens > stimulate an immune response
Acquired immune response
Identify the type of immune response:
T and B Cells
Acquired immune response
evasion mechanism: permits survival of parasites upon entering blood and tissues
Resistance to Infection
Identify the evasion mechanism
Cuticle and integument > resist macrophage
Resistance to Infection
Parasites can reduce immune function of macrophages > lower action of macrophages and defective processing of antigen
Immune Suppression
Identify the evasion mechanism:
Body could not differentiate self from non-self
Host Mimicry
Identify the evasion mechanism:
Echinococcus granulosus larval stages carry P blood
group antigens
host mimicry
Identify the evasion mechanism:
Schistosoma sp. Can acquire antigenic molecules from
host
host mimicry
Identify the evasion mechanism:
Trypanosoma brucei infection:
* variant surface glycoproteins (VSG)
Antigenic Variation
Identify the evasion mechanism:
Plasmodium: antigenic diversity
Antigenic Variation
T/F:
Dysfunction of any of the host defense systems can result in damage to host tissue and produce clinical disease.
True
4 Types of Reaction
- Type 1 (Immediate type hypersensitivity)
- Type 2 (Immune complex formation)
- Type 3 (Cytotoxic reactions of antibody)
- Type 4 (Delayed-type hypersensitivity)
Microspora – now under _______
Fungi
unicellular eukaryotic organisms
Protozoans
“worms”; metazoan parasites
Helminthes
3 types of helminthes
- Nematodes (Roundworms)
- Cestodes (Tapeworms)
- Trematodes (Flukes)
