Quiz 10 Flashcards
You do need to know the steps of the life cycle of malaria. What are merozoites vs sporozoites?
1) parasite undergoes sexual reproduction in its gut cells and releases sporozoites
2) sporozoites spread to salivary glands of the mosquito and wait
3) mosquito bites new host, sporozoites go to liver, where they replicate and become merozoites
– merozoites infect RBCs, kill them, and then move on
Slime molds : cellular slime molds
– what do the cells do when conditions become unfavorable, how do they signal with one another, why do they produce spores
look like amoeba, but can fuse together into large single cells when conditions are unfavorable
- one cell secretes cAMP, and others will migrate towards it
– some cells in the mass will form a stalk and spore cap to allow for spore spread
Slime molds : plasmodial slime molds
– what do the cells do when conditions become unfavorable, how do they signal with one another, why do they produce spores
diploid cell undergoes mitosis many times w/o cytokinesis
- giant cell then moves and spreads as one mass to gain nutrients
- when nutrients are unfavorable, they will separate into different cases and form a stalk and sporangium to release spores in search of nutrients
Helminths
- What are they?
- How do they typically kill people?
- gender?
multicellular macroscopic animals that kill people by directly invading and destroying tissues, or by depleting the body of vital nutrients
may have distinct gender or be hermaphroditic
How are helminths spread?
- ingestion of contaminated food or water
- transferred from an insect
- direct penetration of the skin or body opening
Helminths
- How do parasitic worms differ from free-living worms?
Parasitic worms lack complete digestive system and must obtain nutrients from a host
- reduced nervous system
- reduced locomotion
- enhanced reproduction (produce more eggs)
Roundworms
- What do they look like (more than being round)?
Cylindrical body shape with a tubular digestive tract which extends through the whole body
- usually tapered at each end
Roundworms
- Know the six major types that impact humans (1-3)
1) Ascaris - intestinal roundworm, most common helminth
2) pinworm - inhibit lower digestive tract
3) hookworm - latch onto intestinal wall and feed off of nutrients/blood, causing anemia
Roundworms
- Know the six major types that impact humans (4-6)
4) trichinella - inhabit our muscles
5) whipworm - also intstinal, spread via contaminated water and mostly among kids
6) filaria – multiply in our tissues and clog lymphatic vessels, leading to fluid accumulation
Flatworms
- Know their general structure (e.g. what is the scolex, proglottids, etc)
Flat, ribbon-shaped bodies with a head (scolex) that has hooks and suckers
the segments or proglottids contain reproductive structures
Flatworms
- What is unique about their digestion?
- How are they transmitted?
- they have no digestive system, and absorb nutrients directly from a host
- transmission is usually by eating undercooked contaminated meats
Flukes
- Know their general shape/structure
- How are they characterized?
have a flat, leaflike body with bilateral symmetry, and use multiple suckers to hold organism in place and gain food
classified by the type of tissue they infect (lung fluke, liver fluke, etc.)
Flukes
- What is Schistosoma and how is it spread?
Schistosoma is an infection in humans spread by snails in unclean water and absorbed through the skin
Arthropod vectors
- What are they and what do they do (in general)?
Arthropods are small animals that can act as vectors for transmitting disease
What is the difference between biological and mechanical vectors?
- biological vector : the virus actually has to infect the vector
- mechanical vector : the vector picks up the virus and transmits it to a new host without the vector itself becoming infected
