marine symbiosis midterm 1 HW questions

A microorganisms is defined as an organisms that is too small to be seen clearly with the naked eye and is usually smaller than

1 inch

1 cm

1 mm

1 mm

Which of the following historical figures is known for building the first microscope and discovering "animalcules"

Redi

Leewenhoek

Fracastoro

Schwann

Leewenhoek

Kitasato and Yersin proposed the double helix structure for DNA in 1944

True

False

false

Match each of the historical figures with their notable discoveries

Pasteur

?

Anton de Bary

?

Koch

?

Beadle and Tatum

?

developed anthrax and rabies vaccines

first to use the term “symbiosis”

shows B. anthracis causes anthrax

proposed the one-gene-one-enzyme hypothesis

Amensalism

?

Cooperation

?

Commensalism

?

Mutualism

?

one partner is harmed and the other unaffected or benefits

both partners benefit in a non-obligatory interaction

symbiont benefits and the host is unaffected

an obligatory relationship with reciprocal benefit for both partners

Bdellovibrio is an example of which of the following symbiosis types

Predation

Amensalism

Parasitism

Commensalism

predation

Which of the following are true about the bacterial symbiont, Buchnera?

it is an example of parasitism

it is transferred vertically to hosts

it is an ectosymbiont

it is an endosymbiont

it is transferred vertically to hosts

it is an endosymbiont

Which of the following is a third symbiotic partner recently found in lichens

fungal yeast

virus

bacteria

archaea

fungal yeast

Aposymbiotic hosts occur in horizontal but not vertically transmitted symbioses

True

False

true

Match the terms with the definition

intracellular symbiont

endosymbiont

holobiont

microbiome

extracellular symbiont

ectosymbiont

microbe found inside of host cells

microbe is found within the host

a term to describe the host and all of its microbial symbionts

a term to describe all the microorganisms within a host

microbe is in a body cavity or crypt but not inside host cells

microbe in on the surface of a host

Which class of fish do sharks belong to?

Chondrichthyes

Osteichthyes

Agnatha

chondrichthyes

How long ago did the ancestors of sharks diverge from their other fish relatives?

5 million years ago

450 millions years ago

50 million years ago

450 million years ago

Which TWO of the below sharks are obligate ram ventilators?

Whale shark

tiger shark

lemon shark

nurse shark

Mako shark

whale shark

mako shark

You set a baited long line and pull in two species of sharks: Atlantic sharpnose and hammerheads. All of the sharpnose sharks survive but the hammerheads did not survive. Why?

hammerheads are deep sea fish and can't tolerate lower pressures at shallow depths

sharpnose can actively ventilate and hammerheads are obligate ram ventilators

the bait was poisonous for hammerheads

sharpnose can actively ventilate and hammerheads are obligate ram ventilators

Egg-laying sharks are referred to as

oviparous

viviparous

ovoviviparous

oviparous

Sharks that bear live young with maternal nutrient transfer are referred to as

oviparous

viviparous

ovoviviparous

viviparous

Sharks that reproduce by having eggs hatch internally then are born live are referred to as

oviparous

viviparous

ovoviviparous

ovoviviparous

These types of sharks are born with a "belly button" between their pectoral fins

oviparous

viviparous

ovoviviparous

viviparous

During this type of reproduction, the first shark to hatch will consume the other shark fetuses

oviparous

viviparous

ovoviviparous

ovoviviparous

Cookiecutter sharks use which mode of reproduction

oviparous

viviparous

ovoviviparous

ovoviviparous

Horn sharks use which mode of reproduction

oviparous

viviparous

ovoviviparous

oviparous

You have been asked to observe lemon shark pups and adult male and female great whites to record their preferred prey. What field location would you go to for i) lemon shark pups and ii) adult great whites?

i) Mangroves and ii) South Farallon Islands

i) Gulf Stream and ii) Catalina Island

i) banks and inshore reefs and ii) Gulf Stream

i) Mangroves and ii) South Farallon Islands

Which of the following is true about the conclusions from the cultured bacterial communities study by Black et al from 2021?

the study found Moraxellaceae on all species and Vibrionacea on wounds

the study site was located off the Western coast of Florida

the study found no bacteria on the gills

the study sampled sandbar and catsharks

the study found Moraxellaceae on all species and Vibrionacea on wounds

Which of the following is NOT true about the DNA sequencing-based shark microbiome study by Storo et al. from 2021?

study found distinct microbial community on teeth compared to other body sites

study found Caribbean Reef sharks have distinct microbes compared to other species

sample site was Southeast Florida

study used drumlines to catch Caribbean Reef, Lemon, Nurse, Sandbar, and Tiger sharks

study found the microbial community on sharks was distinct from that of the seawater

study found Caribbean Reef sharks have distinct microbes compared to other species

The ampullae of Lorenzini (AoL) are filled with which of the following (select all correct answers):

cilia

electroconductive jelly

chitin

cellulose

electroconductive jelly

chitin

The culturing experiment from AoL jelly revealed which of the following as the dominant bacterial isolate:

fungi

Staphylococcus

Vibrio

Staphylococcus

In the vibrio-squid symbiosis, V. fischeri is found in which of the following host locations.

light organ

accessory nidamental gland

digestive tract

gametes

light organ

In the vibrio-squid symbiosis, which of the following best describes the interaction between the bacteria and the squid host?

amensalism

obligate mutualism

predation

cooperation

cooperation

In the vibrio-squid symbiosis, which of the following best describes the type of interaction that occurs between bacterial strains via the T6SS?

obligate mutualism

amensalism (interference competition)

amensalism (exploitative competition)

cooperation

amensalism (interference competition)

Which of the following are TRUE about the vibrio-squid symbiosis

Symbiosis is transmitted horizontally

Symbiont receives food from the host

host receives essential vitamins from the symbiont

Model system for neurological disease in humans

Symbiosis is transmitted horizontally

Symbiont receives food from the host

Which of the following are reasons why the squid host vents 90% of the symbiotic bacteria each day?

to decrease the accumulation of toxic metabolites

to control the population size within the animal

to seed the environment for the next generation

to prevent a systemic infection

to control the population size within the animal

to seed the environment for the next generation

Vibrio fischeri is highly abundant in seawater, and this numerical advantage is why it is the only species found in the host.

True

False

false

Which of the following best describes the symbiotic relationship between V. fischeri bacteria and fish or artemia hosts?

parasitic

obligate mutualism

commensalism

cooperation

parasitic

Which of the following are observed effects on zebrafish embryos after exposure to V. fischeri bacteria?

decreased survival

bioluminescent feces

smaller hearts

shorter length

decreased survival

smaller hearts

shorter length

All tested V. fischeri strains used the T6SS1 to kill fish embryos and artemia nauplii

True

False

false

Which of the following is a good approach to test whether a bacterial symbiont is on the surface of a host or colonizing inside the host?

homogenize the entire animal and sequence the DNA

quantify how many bacteria (CFUs) you can recover before and after a brief antibiotic treatment of the host

homogenize the entire animal and plate for CFUs

quantify how many bacteria (CFUs) you can recover before and after a brief antibiotic treatment of the host

Which of the following are lessons learned from studying Vibrio fischeri as a symbiont?

A single bacterium can be pathogenic or beneficial, depending on the host

Beneficial symbionts can still compete with each other

All T6SSs perform the same functions

Vertical symbiont transmission can decrease survivability

A single bacterium can be pathogenic or beneficial, depending on the host

Beneficial symbionts can still compete with each other

Which of the following is NOT true about sponge symbioses

sponges in the photic zone can contain photosynthetic symbionts

sponges contain viruses, bacteria, fungi, and protists

sponge symbionts are always transferred vertically

sponges are an important source of biomedically relevant secondary metabolites

sponge symbionts are always transferred vertically

Match the sponge physiology term with its description

pinacoderm

archaeocytes

ostia

mesohyl

choanocytes

oscula

outer surface of the sponge

phagocytic cells

opening through which water enters the sponge

layer of connective “tissue” were digestion takes place

flagellated cells that create water flow through the sponge

opening through which water is expelled from the sponge

Although the deep sea, carnivorous harp sponge’s microbiome has not yet been explored, which of the following symbionts would you expect to NOT find in this host? (1 pt)

Vitamin-producing bacteria

Predatory bacteria

Viruses

Photosynthetic cyanobacteria

Photosynthetic cyanobacteria

Which of the following is NOT true about Poribacteria: (1 pt)

May be an ancient, vertically transmitted sponge-specific bacterial symbiont

Encodes genes to degrade carbohydrates found in sponge matrix

Produces the anti-cancer drug discodermalide

Is not yet culturable

Produces the anti-cancer drug discodermalide

True or False. The “core” bacterial community comprises the largest proportion of bacterial species in sponges, with very few species-specific bacteria in each sponge host. (1 pt)

True

False

false

Which of the following best describes NW4327? (1 pt)

Cyanobacterial symbiont in Indonesian sponges

Causative agent of disease in Great Barrier Reef sponge

Predominant culturable bacterium in healthy Great Barrier Reef sponge

Is a virus isolated from marine sponge

Causative agent of disease in Great Barrier Reef sponge

In the study by He et al., 2014 that screened 11 sponge species for different protists and fungi, which of the following were found in all 11 sponges (1 pt)

stramenopiles, Haplosporidia, Hapotophyta

Cercozoa, Basidiomycota, Rhodophyta

Ascomycota, Alveolata, and Radolaria

Ascomycota, Alveolata, and Radolaria

Which of the following is considered a secondary metabolite: (1 pt)

amino acids

vitamins

Glucose

antibiotics

antibiotics

Which of the following is NOT true about sponge-derived secondary metabolites (1 pt)

they can be very expensive to harvest and test for bioactivity

many have biotech applications

they are mostly produced by the sponge, not the bacterial symbionts

a single sponge can contain many diverse molecules with different types of activity

they are mostly produced by the sponge, not the bacterial symbionts

Which of the following is NOT a viable method to discover new bioactive compounds in sponges? (1 pt)

microscopy imaging of sponge matrix

sequence the metagenome and look for predicted biosynthetic gene clusters

cultivate bacteria from sponges and screen for functions

screen chemical extracts of sponges

microscopy imaging of sponge matrix

Which of the following is true about the Theonella – Entothenella symbiosis (1 pt)

Entotheonella as a reduced genome size, suggesting an ancient, intracellular association

Entotheonella is not found in the sweater and is likely transmitted vertically

Theonella is native to the Caribbean

Entotheonella is a bacterium found in Theonella that produces bioactive products

Entotheonella is a bacterium found in Theonella that produces bioactive products

Which of the following is NOT true about discodermolide? (1 pt)

has anti-coagulant activity

was patented and licensed to Novartis for development as an anticancer drug

is structurally distinct from Taxol

Found in extracts from a deep-sea sponge

has anti-coagulant activity

Which of the following is NOT a challenge for further characterizing the therapeutic potential of discodermolide? (1 pt)

it is challenging to chemically synthesize

it is insoluble in aqueous solution

the biosynthetic genes have not yet been identified

it is found at very low concentrations inside the sponge

it is insoluble in aqueous solution