Three commonly tested agents are
nicotine, caffeine, and ethyl alcohol
. Scholarly, peer-reviewed reports of how these compounds affect heart rate in Daphnia are scant.
How does temperature affect heart rate in Daphnia?
Acclimation of the waterflea Daphnia magna Straus (Crustacea: Cladocera)
at 2 o to 12 o C above their habitat temperature (16 o C) for 6 months increased
the rate of their metabolic activity (respiration and heartbeat rates).
How does temperature affect Daphnia heart rate lab?
In the immediate submersion,
the colder the water got
, the faster the daphnia's heart beat. However, in the extended submersion, we found that the longer the daphnia was in the colder water, the more the heart beat decreased.
What increases Daphnia heart rate?
The addition of caffeine
increased the heart beats per minute of the Daphnia in each trial. When the caffeine was added, their speed and movement remained the same. A paired T-test was conducted to compare the effect of 5%ethanol on the heart rate of Daphnia.
What temperature do Daphnia like?
lumholtzi performs well at elevated water temperatures. The intrinsic rate of increase (r), net reproductive rate (R
o
), age at first reproduction, survivorship (l
x
) and molting rates all demonstrate that D. lumholtzi has a high temperature optimum
between 20 and 30°C.
What temperature is best for Daphnia magna?
McMahon [14] found the maximum FC of D. magna was 24°C, whereas other authors, all of whom had performed a previous long-term acclimation at 20°C, fixed the optimal temperature as being
between 20 and 21°C
[2,21,31].
What is the normal heart rate of Daphnia?
Average heart rates for the control (204 beats per minute) were higher than all of the other treatments (100, 200, and 300 mg) with averages of
140, 103, and 84 beats per minute
, respectively.
What drugs affects daphnia heart rate?
Aspirin, acetaminophen, and diphenhydramine
slowed the heart rate of the daphnia by 29%, 12%, and 6% respectively. Furthermore, daphnia exposed to aspirin and acetaminophen were associated with arrhythmias, or irregular heart rhythms. All over-the-counter medications tested affected the daphnia's heart rate.
What is the effect of ethanol on daphnia heart rate?
When the daphnia were in 5% ethanol, the rate of their heart change
percent decreased, on average, by 21.70%
, compared to when they were in water, as seen in Figure 1.
Does temperature affect heart rate?
For
every degree the body's internal temperature rises
, the heart beats about 10 beats per minute faster. The result is a dramatic increase of stress on your heart.
Does caffeine make Daphnia heart rate?
Caffeine increases the heart rate
of Daphnia in a dose-dependent manner.
How does sugar affect Daphnia heart rate?
The results of the experiment showed that
high concentrations of sucrose, salt, and caffeine drastically increased the Daphnia's heart
rate. As the concentrations were diluted, the heart rate of the Daphnia decreased, reaching closer to the original heart rate.
What do Daphnia feed on?
Daphnia feed on
small, suspended particles in the water
. They are suspension feeders (filter feeders). The food is gathered with the help of a filtering apparatus, consisting of the phylopods, which are flattened leaf-like legs that produce a water current.
How long can Daphnia survive?
Daphnia usually live
about ten to thirty days
and can live up to one hundred days if their environment is free of predators. An individual will generally have ten to twenty instars, or periods of growth, during their lifetime.
Why do Daphnia turn pink?
Lagoon Daphnia are useful as consumers of algae, improving water clarity and reducing TSS, and controlling bacterial and protozoan populations. … This stress–
due to low food and low dissolved oxygen
–causes them to turn red or pink, resulting in red or pink streaks in the lagoon.
Why are Daphnia red?
When Daphnia are exposed to hypoxic (low oxygen) conditions, they can
increase hemoglobin production
. Due to their clear outer carapace, they will appear red when hemoglobin production has increased.
