chapter 27

which animals are ruminants?

-cattle -camels -giraffes

which two of the following benefits are provided to ruminant animals by methaogenic archaea?

-essential vitamin synthesis -efficient hydrogen removal

in a syntrophic relationship, the growth of one organism depends on (or is improved by) which types of factors produced by nearby organisms?

-growth factors -nutrients -substrates

protists are critical for a termite's ability to consume a diet of only wood. the protists ferment cellulose to ______

-hydrogen -acetate -carbon dioxide

which of these observations that support the idea that endosymbiotic relationships between aphids and bacteria are evolutionarily old?

-over 90% of the genes are common among the various endosymbionts -certain steps in amino acid synthetic pathways occur in only the aphid or the endosymbiont

which 3 of these are characteristics of a host parasite relationship?

-the host must be harmed -the parasite must benefit -the parasite must coexist with the host, at least temporarily

the stomach of a ruminant is divided into how many chambers?

4

certain bacteria living in anoxic, methanogenic ecosystems are called acetogens because they produce ______

acetate

microbes that oxidize ethanol, butyrate, propionate, and other fermentation end products to hydrogen, carbon dioxide, and acetate are called ______

acetogens

an endosymbiotic relationship where one organism releases a compound that has an adverse effect on another is called _______

amensalism

antibiotic production by bacteria is an example of _____

amensalism

because of the environmental conditions in the rumen, all microbes present must function efficiently under _____ conditions

anaerobic

if an aphid is treated with an antibiotic, it dies. which is the best explanation for this observation?

aphids harbor obligate mutualistic bacteria

in a commensalistic symbiotic relationship, the commensal is the partner that ______

benefits

identify the common characteristic of cooperation and mutualism -both involve a modification of the environment -both harm one partner -both are symbiotic relationships

both are symbiotic relationships

in the Riftia worm endosymbiotic bacteria association, the bacteria are ______, using sulfide as an electron donor and oxygen as a terminal electron acceptor

chemolithotrophic

a nonobligatory, symbiotic relationship in which one partner benefits and the other partner is neither harmed nor helped is called _____

commensalism

a nonobligatory, symbiotic relationship in which one partner benefits and the other partner is neither harmed nor helped is called _______

commensalism

when different organisms within a population or community try to acquire the same resource, this is called ______-

competition

termites are dependent on their endosymbiosis to carry out which two of these processes?

convert (fix) nitrogen to a useable form + complete the digestion of cellulose

a symbiotic relationship in which each partner receives some benefit, but each partner can also live independently is called _______

cooperation

ruminants are said to have an "eat now, digest later" strategy, because after feeding on grasses, they spend vast amounts of time chewing a small ball of partially digested grasses called their ______

cud

marine invertebrates like sponges, jellyfish and corals often harbor zooxanthellae, which are endosymbiotic ________

dinoflagellates

according to gause's competitive ______ principle, if one of two competing organisms can dominate an environment, it will overtake the other organism

exclusion

protists convert the cellulose derived from a termite's wood diet to its preferred carbon source, acetate, through the process of ______

fermentation

in various anoxic methanogenic ecosystems, fermentative bacteria, like Syntrophobacter, produce excess H2, which is consumed by methanogenic archaea to produce methane. this process is known as ______ hydrogen transfer

interspecies

efficient hydrogen removal and the production of vitamins are two benefits to ruminant animals conferred by _______

methanogens

mutualistic relationships between microbes and insects are common because insects _______

often consume diets lacking essential nutrients

in the Riftia worm endosymbiotic bacteria association, the bacteria are chemolithotrophic, using sulfide as an electron donor and ______ as a terminal electron acceptor

oxygen

an antagonistic interaction in which one partner obtains biochemical precursors and energy from a living a victim is termed _____

parasitism

an endosymbiotic relationship where one partner benefits and one is harmed, but also involved at least a temporary state of coexistence is called _______

parasitism

an antagonistic interaction in which one partner obtains biochemical precursors and energy after killing a victim is termed _____

predation

the rumen contains a diverse microbial community that includes which type of organisms?

protists, bacteria, fungi, archaea

in mutualistic associations between microbes and insects, the microbe generally receives ______

secure habitat and ample nutrients

the stable association of one organism with another is called _______, regardless of the outcome

symbiosis

an association in which the growth of one organism depends upon, or is improved by, factors provided by a nearby organism is called _____-

syntrophy

the rumen has a slightly higher _____ than the rest of the animal

temperature

omasum

the antechamber ; part of the lower portion

reticulum

the honeycomb like part of the upper portion

rumen

the large, muscular, fermentation chamber

abomasum

the true stomach ; part of the lower portion

true or false :a diet of wood lacks nitrogen, and therefore termites require assistance from organisms that can provide nitrogen

true

marine invertebrates often harbor endosymbiotic dinoflagellates called ______-

zooxanthellae