Section 25.2 (Exam 2) Flashcards
Major Lineages of Eukaryotes Diversified in the Precambrian
What are Rhizaria?
Unicellular, aquatic, protists with long and thin pseudopods
Name three types of Rhizaria.
Cercozoans, Foraminiferans, Radiolarians
Foraminiferans secrete shells of _____________.
calcium carbonate.
Foraminiferan shells, made of calcium carbonate, accumulate over millions of years to form __________ deposits.
limestone
Foraminiferans have threadlike, branched ____________, that extend through numerous pores in the shell and form a sticky ____ that captures smaller plankton.
pseudopods; net
Radiolarians have radial symmetry and thin, stiff, pseudopods reinforced by ___________.
microtubules
Pseudopods in radiolarians increase surface area, for exchange _________________ and _________________.
of materials and helps the cell float.
Radiolarians are exclusively _________ and most have glassy internal skeletons with elaborate designs made from ________________.
marine; silicon dioxide
One type of radiolarian with symbiotic dinoflagellates is called ____________________.
Amphilonche heteracantha
Excavates have many diverse groups and some lack ________________.
mitochondria
Name 5 types of excavates.
Diplomonads, Parabasalids, Heteroloboseans, Euglenids, Kinetoplastids
Diplomonads and parabasalids lack ___________ which is a ___________ trait.
mitochondria; derived
Name a diplomonad.
Giardia lamblia
Name some characteristics of the diplomonad Giardia lamblia.
Has two nuclei and multiple flagella. Water-borne parasite that causes an intestinal disease - giardiasis.
Parabasalids have ______________ membranes for locomotion in addition to _____________.
undulating; flagella
One example of a parabasalid is ______________________.
Trichomonas vaginalis
What is trichomonas vaginalis and what is it also called?
A human STD, also called trichomoniasis.
Heteroloboseans is an excavate with an ________________ body form.
amoeboid
One example of a heterolobosean is ____________. It causes a fatal nervous system disease called _____________________, or also commonly known as the brain-eating bacteria/amoeba.
Naegleria; amebic encephalitis.
Euglenids and kinetoplastids share which 4 traits.
Unicellular; have flagella
Flagella contian crystalline rod not found in other organisms
Mitochondria have disc shape.
They reproduce primarily by binary fission.
Euglenids have spiral strips of __________ under the plasma membrane that control ______________.
proteins; cell shape
Are Euglenids photosynthetic or heterotrophic?
They can be either one, and sometimes can switch between both.
Kinteoplastids are parasites with ___ flagella and ___ mitochondria.
two; one
The mitochondrion of Kinetoplastids have a _____________, which is a structure with multiple circular ___________________.
kinetoplast; DNA molecules and proteins
What are two examples of kinetoplastids?
Trypanosoma brucei (sleeping sickness) and Trypanosoma cruzi (Chagas disease).
The body has trouble creating antibodies for trypanosomes because they frequently change the _________________________.
shape of their cell surface
What are the 5 major clades of protists?
Alveolates, Stramenopiles, Rhizarians, Excavates, Amoebozoans
Amoebozoans have lobe-shaped ____________ that are used for ______________.
pseudopods; locomotion
What are the three types of Amoebozoans?
Loboseans, plasmodial slime molds, cellular slime molds
Loboseans, a type of amoebozoan feed by ___________.
phagocytosis
Loboseans a type of amoebozoan are _______cellular.
unicellular
Loboseans live at the bottom of _________________.
lakes and ponds.
Loboseans are testate amoebas that secrete _________ or glue ______________________________.
shells; sand grains together to form a casing
Plasmodial slime molds are amoebozoans. During their vegetative (feeding) stage, they are _______________. A wall-less _____________ with many ______________.
coenocytes; mass of cytoplasm; diploid nuclei
The mass of plasmodial slime molds streams over the substrate in a network of strands called a _______________.
plasmodium
The plasmodium of plasmodial slime molds engulfs food particles via _________________.
endocytosis
If there is food, a plasmodium can grow _______________.
indefinitely
