Chapter 6

Question 1

What two groups of aquatic animals dominate the research field?

Answer 1

amphibians and fish

Question 2

What is the widest used amphibian in research?

Answer 2

Xenopus

Question 3

What was developed in the toxicology field that was made as a toxicology screening assay in which chemicals are tested on the developmental stages of embryos for effects of malformation, growth inhibition, and mortality?

Answer 3

Frog Embryo teratogenesis Assay - Xenopus (FETAX)

Question 4

what is the most common aquatic vertebrate used in biomedical research?

Answer 4

Zebrafish (Danio rerio)

Question 5

Why are zebrafish a powerful model for studying gene function?

Answer 5

their internal anatomical structures are visible within the first 5 days of embryonic development

Question 6

What is the primary enclosure for aquatic species?

Answer 6

immediate tank environment

Question 7

What are most aquatic tanks made from?

Answer 7

polycarbonate or polysulfone plastic

Question 8

what materials for tanks can result in illness and death?

Answer 8

metals or stainless steel

Question 9

What system has individual tanks that work well for both small and large groups of animals, but need frequent changes and water changes?

Answer 9

static

Question 10

What type of system is common in research facilities where water is recirculated but has a specific volume of water changes to introduce fresh water into the system, but can be bad if there is a water quality issue or a disease outbreak?

Answer 10

Recirculating systems

Question 11

What system runs a constant low flow of water into and out of the tank without water circulation, but can be disruptive to species that prefer static water?

Answer 11

flow-through systems

Question 12

How does cleaning of an aquatic system differ from rodent cage cleaning?

Answer 12

you cannot use detergents on aquatic systems

Question 13

What is included in the primary enclosure of aquatic species?

Answer 13

filtration systems

Question 14

an aggregate of microorganisms is desired on tank walls

Answer 14

true

Question 15

What is one of the most important aspects of aquatic husbandry?

Answer 15

water quality

Question 16

what is one surprising thing that amphibians are sensitive to?

Answer 16

latex gloves

Question 17

What temperature do tropical amphibians need water at?

Answer 17

21C-29C (70-85F)

Question 18

What temperature do temperate region amphibians need?

Answer 18

18-22C (65-72F)

Question 19

What temperature are zebrafish colonies kept at?

Answer 19

24-28C (75-82F)

Question 20

What is pH?

Answer 20

the number of hydrogen ions in a system

Question 21

What does the pH scale range from, and what is neutral?

Answer 21

0-14, 7 is neutral

Question 22

What values on the pH scale are acidic?

Answer 22

lower than 7

Question 23

What values on the pH scale are basic/alkaline?

Answer 23

higher than 7

Question 24

What pH do most aquatic species prefer?

Answer 24

6.8-7.1

Question 25

How does varying pH affect ammonia in water?

Answer 25

ammonia becomes toxic in alkaline/basic conditions

Question 26

what can you add to the water to raise the pH of water?

Answer 26

add sodium bicarbonate or calcium carbonate

Question 27

what can you add to water to lower the pH?

Answer 27

glacial acetic acid and hydrochloric acid.

Question 28

what must you remove from municipal water before use in tanks?

Answer 28

chlorine

Question 29

What chemical is used in place of chlorine because it has lower levels of carcinogenic byproducts but is more toxic to aquatic life?

Answer 29

chloramines

Question 30

What is the best way to remove chloramines?

Answer 30

catalytic carbon filter or treatment with sodium thiosulfate

Question 31

What is the measure of the amount of dissolved salts and minerals, present as ions, within an aqueous solution, which is the flow of electricity?

Answer 31

conductivity

Question 32

What happens if there are too many ions in the water?

Answer 32

the water will flow out of the animals' body into the water

Question 33

what happens if there aren't enough ions in the water?

Answer 33

water will flow into the animal and cause an overload of the circulatory and excretory systems

Question 34

what is the term for the flow of water across a water-permeable barrier?

Answer 34

osmosis

Question 35

what is a measure of the amount of specific ions dissolved in water?

Answer 35

water hardness

Question 36

what minerals can be found in harder water?

Answer 36

calcium, magnesium

Question 37

What pH does hard water lean toward?

Answer 37

alkaline/basic

Question 38

What is the measure of oxygen molecules in the water?

Answer 38

dissolved oxygen (DO)

Question 39

What happens to DO when the temperature rises in the water?

Answer 39

oxygen will diffuse out of the water

Question 40

What is gas bubble disease?

Answer 40

when oversaturation of water with dissolved gases causes side effects in fish or amphibians and can cause rapid death

Question 41

what are methods of purifying water?

Answer 41

reverse osmosis, deionization, distillation

Question 42

for what purpose are buffering chemicals added to an aquatic system?

Answer 42

to adjust the pH

Question 43

what type of filters are available?

Answer 43

biological, mechanical, and chemical

Question 44

what is an inert/stable substance, typically silicone, gravel, glass, or plastic, with a high surface are that acts as a substrate to bind large numbers of nitrifying bacteria?

Answer 44

biological filter

Question 45

what happens to ammonia and nitrite levels when a biological filter is first added to a tank?

Answer 45

rise dramatically

Question 46

what is 'new tank syndrome?"

Answer 46

when ammonia and nitrite levels rise drastically when a biological filter is first added

Question 47

what is the process of breaking down waste ammonia into less toxic byproducts?

Answer 47

nitrogen cycle

Question 48

where does the nitrogen cycle take place?

Answer 48

in the biological filter

Question 49

what are the less toxic byproducts of ammonia?

Answer 49

nitrites and nitrates

Question 50

what method physically removes solid waste from the tank?

Answer 50

mechanical/particulate filter

Question 51

what method dissolves minerals and compounds, including wastes, that may pass through the mechanical filter.

Answer 51

chemical filtration

Question 52

what light can kill microorganisms living in a tank?

Answer 52

UV light

Question 53

what is the germicidal spectrum for killin microorganisms but can cause mutations in DNA?

Answer 53

200-280 nanometers

Question 54

what is the standard for the flow rate of water into and out of the tank?

Answer 54

usually 5-6 per hour

Question 55

what type of outlets should aquatic facilities have for safety?

Answer 55

ground-fault circuit interrupted (GFCI)

Question 56

why is backup power so important?

Answer 56

to prevent catastrophic death due to DO depletion

Question 57

what is the best humidity for aquatic facilities?

Answer 57

50-80%

Question 58

what light levels should you keep fish at?

Answer 58

100-150 lux

Question 59

what light is not recommended in zebrafish rooms?

Answer 59

red light due to their red-sensitive cone cells

Question 60

how far above the floor should electrical outlets be located?

Answer 60

1m

Question 61

Why does the germicidal spectrum have to be in a certain wavelength range?

Answer 61

to cause a limitation in microorganism replication

Question 62

which parameter is is acceptable to check on a weekly basis, rather than daily?

Answer 62

hardness (measure of calcium and magnesium in water)