How does ethanol effect heart rate?
The cardiovascular system is affected by alcohol. At the time of drinking, alcohol can cause a temporary increase in heart rate and blood pressure. In the long-term, drinking above the guidelines can lead to on-going increased heart rate, high blood pressure, weakened heart muscle and irregular heartbeat.
What effect does alcohol have on the heart rate of Daphnia?
1. Alcoholic beverages have decreasing effect on the heart rates of Daphnia. As the concentration of alcoholic beverages increases, the heart rate of Daphnia decreases.
Does ethanol slow down heart rate?
Ethyl alcohol caused a dose-dependent and reversible decrease in mean heart rate (Figure 2A).
How does caffeine affect the heart rate in Daphnia Why?
Both caffeine and dopamine were found to instantly increase the heart rate of Daphnia in a dose-dependent manner. Interestingly, caffeine synergized with dopamine to increase Daphnia's heart rate.
Why does alcohol increase your heart rate?
A heart rate increase is a natural reaction to alcohol Alcohol makes your blood vessels dilate and get larger, which makes the heart muscle pump more blood to keep the same amount in the body. To do this, it'll need to pump harder and faster to keep the same amount of blood circulating.
Is ethanol a depressant or stimulant?
Many people use alcohol to enhance their mood, but alcohol is actually a Depressant that can negatively affect one's mental and physical health.
Does alcohol affect heart rate variability?
Heart rate variability (HRV) and resting heart rate are two of the most useful metrics for quantifying your fitness on a daily basis. Consuming alcohol causes your HRV to drop (bad) and your resting heart to rise (also bad).
What is the control variable in the Daphnia experiment?
In the case of our Daphnia, an example of a controlled variable would be the temperature of the water in which the Daphnia are tested. This variable needs to be controlled because Daphnia hearts beat faster in warm water than they do in cold water.
How does pH affect Daphnia heart rate?
A pH of 3 and 4 will have the effect of the daphnia to have a high heart rate compared to a pH of 7. A base of 10 and 11 will have the effect of the daphnia to have a lower heart rate than the pH of 7. The locomotion of the daphnia will be much higher in the acidic pHs compared to the basic pHs.
How does Daphnia increase heart rate?
Daphnia is poikilothermic, which means that its body temperature and therefore its metabolic rate are affected directly by the temperature of the environment. The change in metabolic rate is reflected in the rate at which the heart beats (cardiac frequency).
Why does caffeine increase heart rate?
Caffeine affects the heart in multiple ways. Firstly, it promotes the release of noradrenaline and norepinephrine. Among other things, these hormones increase heart rate and blood pressure. Additionally, caffeine can act on enzymes that stimulate heart contractions, causing the heart to contract with more force.
How does caffeine affect the heart rate of Daphnia independent variable?
The independent variables are the seven caffeinated solutions that are tested on the Daphnia magna. It is hypothesized that caffeine solution with higher concentrations of caffeine will cause two effects: an increase in heart rate and a higher increase of heart rate in pregnant Daphnia compared to nonpregnant Daphnia.
Does alcohol decrease heart rate?
Alcohol is a 'depressant' drug, meaning your brain's control of your body is being slowed down. Even a small amount can affect important functions like speech and movement. Drinking very large amounts all at once can slow your heart rate and breathing down to a dangerously low level.
How does pH affect daphnia heart rate?
A pH of 3 and 4 will have the effect of the daphnia to have a high heart rate compared to a pH of 7. A base of 10 and 11 will have the effect of the daphnia to have a lower heart rate than the pH of 7. The locomotion of the daphnia will be much higher in the acidic pHs compared to the basic pHs.
Why does caffeine increase heart rate a level biology?
In humans, caffeine is a stimulantwhich increases heart rate by increasing releaseof excitatory neurotransmitters.
How is daphnia heart rate measured?
Investigation: What Factors Affect the Heart Rate of DaphniaUsing a clean pipette, carefully transfer a Daphnia and ONE drop of liquid onto a slide. ... Place the slide under the microscope and focus on the Daphnia so that you can see the beating heart. ... Count the number of heart beats that occur in 10 seconds.More items...
How long do daphnia stay in ethanol?
Each Daphnia will stay in the ethanol solution for exactly 3 minutes so that an equal volume of ethanol is absorbed.
What is the dependent variable of the Daphnia experiment?
This will be the independent variable. The dependent variable is the heart rate of the Daphnia.
How long to keep daphnia in Petri dish?
5. Keep the Daphnia in the Petri dish for 3 minutes, this lets it “adapt” do the conditions and also increases the probability of it surviving the whole experiment. With the normal size syringe take it out of the Petri dish and put it onto the microscope slide, make sure that it is practically immobile (by making sure that you squirted the least amount of water possible) and put it under the microscope. Turn the microscope on.
Why did the Daphnia slide die?
The Daphnia used in the first experiment died after being placed on the cavity slide from the 0.6% ethanol solution probably due to the lack of fluid on the slide so I had to restart the experiment using another Daphnia.
Why do daphnias get stressed?
Time left under the microscope – If the Daphnia are left under the microscope for too long they will become stressed due to the heat of the microscope light and this will increase the heart rate of the Daphnia due to the secretion of adrenaline therefore I must ensure that the microscope is switched off when not in use. The cavity slides must be allowed to cool down before using them again as they tend to heat up.
How much ethanol to add to distilled water?
0.8%: Add 8 ml of the 1% ethanol, to 2 ml of distilled water
Does the size of a daphnia affect the absorption of ethanol?
Size of Daphnia – The size of the Daphnia will affect its absorption of Ethanol and also the metabolism of the drug in the liver. Different rates of metabolism will result in different heart rates. As a result I must ensure that I choose Daphnia which are the same size when conducting repeats. I will use a highly sensitive scale to confirm that both daphnia are of equal body mass.
How to count the heart beats of Daphnia?
The heart beat of Daphnia is very rapid, so count the beats by making dots on a piece of paper in the shape of a letter S. Count the dots and express heart rate as number of beats per minute. f At the end of the investigation, return the Daphnia to the stock culture. Investigating the effect of temperature.
How to treat daphnia?
Take care handling any chemicals that might affect the heart rate of Daphnia. Observe normal, good laboratory hygiene practices when completing the practical. Preparation. a Take a small piece of cotton wool, tease it out and place it in the middle of a small Petri dish.
How to make a pond with ethanol?
Mix well. Draw the pond water off the Daphnia with a pipette and replace it with 2 or 3 cm 3 of the water containing ethanol ( Note 3 ). Record the rate of heart beat again.
Which neurotransmitter slows heart rate?
Acetylcholine: In humans and many other animals, heart rate is slowed by the parasympathetic nervous system (neurotransmitter: acetylcholine) via activation of cell surface receptors in the sinoatrial node (pacemaker) called acetylcholine muscarinic receptors.
Which hormone increases heart rate?
Noradrenaline and adrenaline: In contrast, heart rate is increased by the sympathetic nervous system (neurotransmitter: noradrenaline) and the hormone adrenaline circulating in the blood via activation of cell surface receptors in the sinoatrial node - pacemaker) (called beta-1 adrenoceptors).
What is the effect of a slowed heart rate on the body?
A slowed heart rate and the associated fall in the rate of ejection of blood from the heart is sufficient to maintain body function during rest, and conserves energy in the heart under conditions where its supply (and the supply of oxygen in the blood) are diminished.
Where is the beating heart in a petri dish?
The beating heart is located on the dorsal side just above the gut and in front of the brood pouch (see diagram).
Does ethanol lower blood pressure?
Ethanol did reduce slightly the stress-induced tachycardia but markedly reduced or antagonized stress-induced blood pressure increases. No major changes in the ECG were noted during these studies with the exception of a few individual animals which showed pathologic ECG responses to ethanol. These data show that ethanol affects cardiovascular ...
Does ethanol affect heart rate?
Effect of ethanol on heart rate and blood pressure in non stressed and stressed rats. The effect of ethanol on the cardiovascular system (ECG, heart rate, blood pressure) was studied in anesthetized, nonstressed or stressed rats. In anesthetized rats, ethanol showed no effect on heart rate or ECG.
Does ethanol cause tachycardia?
This ethanol induced tachycardia seemed the result of a direct stimulation of the sympathetic nerves to the heart. Blood pressure was not significantly affected by ethanol in these nonstressed rats. In stressed rats, marked behavioral excitation and significant increases in heart rate and blood pressure were noted.
Lesson Organisation
Health & Safety and Technical Notes
- With Daphniacultured in the laboratory, fed on yeast, Liquifry No.1, Spirulina or egg-yolk medium, there are no significant hazards associated with this procedure. With pond water culture, or other sources of food, more careful hygiene precautions are necessary. 1 Keeping live cultures of Daphnia: These notes are based on information in the CLEAPSS Laboratory Handbook. You will f…
Ethical Issues
- Teachers should be careful to introduce these animals in a way that promotes a good ethical attitude towards them and not a simply instrumental one. Although they are simple organisms that may not 'suffer' in the same way as higher animals, they still deserve respect. Animals should be returned promptly to the holding tank after being examined. This supports ethical approache…
Procedure
- SAFETY: Take care handling any chemicals that might affect the heart rate of Daphnia. Observe normal, good laboratory hygiene practices when completing the practical. Preparation aTake a small piece of cotton wool, tease it out and place it in the middle of a small Petri dish. b Select a large Daphniaand use a pipette to transfer it onto the cotton...
Teaching Notes
- Daphniais poikilothermic, which means that its body temperature and therefore its metabolic rate are affected directly by the temperature of the environment. The change in metabolic rate is reflected in the rate at which the heart beats (cardiac frequency). The effect of temperature on a metabolic activity may be expressed in terms of the temperature coefficient (Q10). This is the ra…
Background Information: Chemicals and The Heart
- Acetylcholine: In humans and many other animals, heart rate is slowed by the parasympathetic nervous system (neurotransmitter: acetylcholine) via activation of cell surface receptors in the sinoatrial node (pacemaker) called acetylcholine muscarinic receptors. This occurs after feeding, during sleep, and during breath-holding and swimming underwater. A slowed heart rate and the …
Related Experiments
- Observing the effects of exercise on the human body Compare the results of this experiment with the results of the investigation into the effects of exercise on human heart rate.