Chapter 25 Flashcards
(17 cards)
If eukaryotic mitochondria and chloroplasts resulted from endosymbiosis, what features might these organelles contain?
A. a plasma membrane, DNA, and ribosomes
B. a plasma membrane, nucleus, and ribosomes
C. nucleus, DNA, and ribosomes
D. a plasma membrane, nucleus, and cilia
E. nucleus, ribosomes, and cilia
A. a plasma membrane, DNA, and ribosomes
Which correctly describes slime molds?
A. Cellular slime molds have haploid zygotes.
B. Cytoplasmic streaming helps distribute nutrients and oxygen in cellular slime molds.
C. In plasmodial slime molds, the haploid condition is the dominant part of the life cycle.
D. Cellular slime molds have fruiting bodies that function in sexual reproduction.
E. Cellular slime molds form masses when food is scarce, but their cells remain separated.
E. Cellular slime molds form masses when food is scarce, but their cells remain separated.
The largest group of eukaryotic organisms is the ________.
A. vertebrates
B. animals
C. plants
D. protists
E. fungi
D. protists
Photosynthetic eukaryotes contain both mitochondria and chloroplasts. Which sequence best describes the evolution of
this group?
A. Ancestral anaerobic prokaryote engulfs heterotrophic
prokaryote and then engulfs photosynthetic prokaryote.
B. Ancestral anaerobic prokaryote engulfs photosynthetic
prokaryote and then engulfs heterotrophic prokaryote.
C. Both sequences are equally likely.
A. Ancestral anaerobic prokaryote engulfs heterotrophic
Diatoms, a type of phytoplankton, are surrounded by relatively dense silica cases and lack flagella. Consequently, what is their greatest challenge for survival?
A. withstanding pressure
B. being eaten by a variety of protists and invertebrates
C. surviving in low nutrient concentrations
D. sinking below the photic zone
E. C and D
E. C and D
Which is an incorrect statement about red tides?
A. They cause massive fish kills.
B. They are produced by periods of explosive growth, or blooms.
C. Coastal waters change color due to pigments within plastids.
D. Molluscs may accumulate toxins that cause illness in humans who consume them.
E. They are caused by protists, which move by means of cilia.
E. They are caused by protists, which move by means of cilia.
Which most likely arose from endosymbiosis?
A. nuclear membrane and Golgi apparatus
B. ER and chloroplasts
C. chloroplasts and mitochondria
D. mitochondria and Golgi apparatus
C. chloroplasts and mitochondria
Which evidence supports the endosymbiotic origin of mitochondria
and plastids?
A. Not all eukaryotes have plastids.
B. Eukaryotes are combination organisms.
C. Chloroplasts and mitochondria have their own DNA similar to bacterial chromosomes.
D. The most basal eukaryotic lineage consists of organisms
without conventional mitochondria.
C. Chloroplasts and mitochondria have their own DNA similar to bacterial chromosomes.
What is the identity of the host cell that ultimately led to the origin of the eukaryotes?
A. an archaean
B. a protoeukaryote
C. A or B
D. a photosynthetic cyanobacterium
C. A or B
A difference between primary and secondary endosymbiosis is that ________.
A. secondary endosymbiosis involves ingestion of a bacterium by a eukaryotic cell
B. cells resulting from secondary endosymbiosis may have plastids surrounded by four membranes
C. the descendants of primary endosymbionts were nonphotosynthetic
D. secondary endosymbiosis takes place only in prokaryotes
B. cells resulting from secondary endosymbiosis may have plastids surrounded by four membranes
Which was not a step in the origin of multicellular animals?
A. Cells needed to evolve new ways to adhere (attach).
B. Cells needed to evolve new ways to signal (communicate).
C. Cells needed to evolve new ways of using proteins or parts of proteins encoded by genes used for other purposes.
D. Cells needed to evolve a genetic toolkit composed of many novel genes.
D. Cells needed to evolve a genetic toolkit composed of many novel genes.
Which group of eukaryotes was formerly classified in the kingdom Protista?
A. fungi
B. animals
C. diatoms
D. land plants
C. diatoms
Until recently, the protists in which two groups were thought to lack mitochondria?
A. diplomonads and parabasalids
B. diatoms and brown algae
C. chlorophytes and charophytes
D. tubulinids and slime molds
E. choanoflagellates and animals
A. diplomonads and parabasalids
The gene study of dihydrofolate reductase (DHFR) and thymidylate
synthase (TS) DNA sequences showed that _______.
A. bacteria have separate genes for DHFR and TS
B. fused genes were found commonly in certain members of Excavata, SAR, and Archaeplastida
C. fused genes are a derived character
D. unikonts had the ancestral condition
E. All of the choices are correct.
E. All of the choices are correct.
Which is (are) an example(s) of a mutualistic association between protists and other species?
A. dinoflagellates and coral polyps
B. the stramenopile Phytophthora ramorum and oak trees
C. the stramenopile P. infestans and potatoes
D. the hypermastigote (parabasalid) and termite species
E. A and D
E. A and D
In the majority of the 10 ocean regions studied, the relationship between change in sea surface temperatures (S ST) and concentration of chlorophyll is correctly described by which of these statements?
A. SST and chlorophyll concentration are positively correlated.
B. SST and chlorophyll concentration are negatively correlated.
C. There is no relationship between S ST and chlorophyll concentration.
D. There is a reciprocal relationship between S ST and chlorophyll
concentration.
B. SST and chlorophyll concentration are negatively correlated.
Drugs that target merozoite apicoplasts may work to counteract drug resistance in the parasite that causes which disease?
A. mycoplasmal tuberculosis
B. amoebic dysentery
C. malaria
D. wolbachia
C. malaria
