• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5

# Measure the heart rate of Daphnia at different temperatures

Extracts from this document...

Introduction

Coursework Equipment * Compound microscope, light source, and lens tissues * Animal Cell and a spare cover slip * Petri Dish base * Paint Brush * Small beaker for collecting water * Supply of ice/warm water * Thermometer. * Basis electronic calculator * Pipette Aim To measure the heart rate of Daphnia at different temperatures Method Here is a method to show how I am going to conduct my experiment. Set up a microscope with a level stage. Half fill a petri dish base with tap water. Transfer Daphnia from its culture by using paint brush and place it in the special cover slip. The daphnia is placed in a tiny plastic ring, which is attached to the cover slip. Place another cover slip on top of the cell to retain the trapped animal, unharmed. Gently turn 'sandwich' over, holding it between finger and thumb, and then placing it under the surface of water of the petri dish. Place petri dish on stage of the microscope, examine using lowest magnification until heart is located, and change to highest magnification to see the heart in more detail. ...read more.

Middle

111 123 144 135 138 Daphnia 3 66 78 84 93 105 105 144 129 135 150 120 90 These results have been plotted onto a line graph. Hypothesis During this experiment I believe I will come across the following results. * The amount of heart beats at the different temperatures will not vary a lot. * The Daphnia's heart will stop once the temperature has exceeded 30 degrees Celsius. * Around 25 degrees Celsius would be the optimum temperature for which there would be the greatest number of heartbeats. * The 3 sets of Daphnia will have similar results. * The results will not be completely accurate because the heart rate count will be hard to record due to the how quick it will be beating and because the daphnia will not be in focus all of he time as it moves around a lot. Diagrams Water fleas are easy to find. Most ponds will provide enough of these small crustaceans. They are ideal subjects for study under the microscope. ...read more.

Conclusion

Moina withstand extremes even more, resisting daily variations of 5-31 deg C (41-88 F); their optimum being 24-31 deg C (75-88 F). From my results I found that the optimum temperature for the Daphnia is 40 after calculating the average of each temperature the Daphnia was exposed to. My hypothesis is that with an increase in temperature a Daphnia's heart rate will increase. The reason for this is that the chemical reactions that occur in the Daphnia are dependent on certain enzymes, or proteins to help them proceed. As the temperature of the water is increased, the metabolism of the Daphnia increases also; this is due to chemical reactions occurring faster at higher temperatures due to an increase in kinetic energy. As a consequence of this increase, the heart has to beat faster as more Carbon Dioxide is produced from the cells during respiration. This can cause acidic conditions which will eventually denature enzymes, so more oxygen needs to circulate which is why the heart speeds up. The results also show that with the decrease in temperature less cell respiration is occurring and so the heart beats at a slower pace. Kieron Harper ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Humans as Organisms section.

## Found what you're looking for?

• Start learning 29% faster today
• 150,000+ documents available
• Just £6.99 a month

Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Related GCSE Humans as Organisms essays

1. ## Effect of Ethanol on the Daphnia heart rate

After doing the 0.2% concentration, the average decrease in heart rate per concentration increase (+0.2) is 9 b/m. Taking into account the first change, the average decrease would be 15 b/m. With the 9 b/m average decrease, it would be interesting to see if heart rate is approximately 241 b/m - 9 b/m (=232 b/m)

2. ## Stem Cell Research

The main reason that this source believed that adult stem cells were superior was because they avoided ethical issues. This book seems to place more emphasis on the ethical issues of embryonic stem cell research than the medical potential of them.

1. ## Coursework on the heart rate of the daphnia

Method To determine if temperature does have an effect on the daphnia, I intend to carry out the following experiment. The experiment will involve measuring the cardiac activity of the daphnia at different temperatures, ranging from very cold (approx. 5 degrees Celsius)

2. ## Investigating The Effect Of Drugs On the Heart Rate of a Daphnia.

Once I have done that I will take the slide and absorb the solution which the daphnia has been swimming in. I will then put the daphnia back into it fresh water. I will then prepare the solution which will have 0.2 ml of the 1% alcohol and 0.8 ml of distilled water.

1. ## The heart rate of a Daphnia (water flea)

I will set up the apparatus as shown below: Variables & Fair Testing The variables that could affect the experiment are: Temperature of the water, quantity of water, time taken for the Daphnia to adapt to its new environment, impurities in the water and the original habitat of the Daphnia.

2. ## The Heart Rate of Daphnia Under Different Conditions

* After identifying the heart beat, count how the hearts beats in 10 seconds. * Record this in forms of dots. * Repeat this three times and take the average. * Take the different solutions of drugs and using a pipette take up some.

• Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to
improve your own work