The Youth Scientists Journal

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Posted on: 17 August 2009

Members : Benjamin, Nadiah, Haryani & Darren
In this week practical, we are investigating the effects of different exercises on the human body. Our subject for the activity given is Darren, one of our team members who are assigned to doing star jumps continuously for 5 minutes. We measure the breathing rate, heart rate, body temperature and the oxygen concentration before the experiment started which then Darren had to start jumping for 20 seconds before we measure the breathing rate, heart rate, body temperature and the oxygen concentration again.
Oxygen Temperature Heart Rate Breathing Rate
Before exercise 11.4 31 100 1.1
1st (star jump) 0.4 33.8 102 1.7
2nd (star jump) 0.38 36 90 1.6
3rd (star jump) 0.39 30.5 144 0.98
4th (star jump) 0.24 37 126 1.67
5th (star jump) 0.24 35.6 132 1.7
6th(resting) 11.38 31.5 100 1.3
7th (resting ) 11 30 120 1.8
8th (resting ) 11.25 31.1 72 1.6
9th (resting ) 11.4 31.5 102 1.7
10th(resting) 10.98 31.25 114 1.6
The results is inaccurate because of human and random errors
• where we took a longer to set up the equipment to recorded the readings.
• Oxygen sensor set up wrongly
• The time (20s) was delayed as we forgotten about it
• Hence, Darren was left to doing more star jumps


Group Members: Benjamin Ang (leader), Nadiah Nadhirah, Nur Haryani

Firstly, to summarise the whole chapter 8 – Transport in Human. It is about the transfer of substances from one part of the body to another through a transport system. This occurs due to the complex multi-cellular system, where numerous cells are situated deep in the body. Hence simple diffusion or osmosis cannot transport substances to and fro.

The first part of the experiment as stated above is to identify parts of the heart externally, such as anterior vena cava, aortic arch, pulmonary arch, pulmonary artery, pulmonary vein, left atrium, right atrium & etc. and internally, identifying the blood vessels, white and red blood cells, understanding the structures of the blood vessels and its function and describe the structures of blood vessels, red and white blood cells.

As shown above, Benjamin has labelled the part of the heart structure that he identified with the pins given as instructed.
Firstly, we differentiated the left and right atrium of the heart and poke the other parts with a glass rod to identify the rest of the parts of the heart.

Pictures of microscope slides




Respiration is a very important process in our body. It allows us to live, and in every way is indeed a miracle. Without this process in our body, it would be very difficult for us to survive. It enables our body to take in clean oxygen and send it to the rest of the body. It also helps in ridding the body of carbon dioxide.

During this practical we had the opportunity to do an experiment on one of our group members, Lee Youzheng. We measured and recorded his body temperature and heart rate, along with his breathing rate and the amount of oxygen concentration there was in the surrounding air, before the experiment stared.

He did ten sit-ups and push-ups for a minute before we took the necessary measurements. He did this for four more times and stopped at the fifth minute. We then allowed him too cool down and did the test over again after every minute for five minutes.

Watch the whole experiment here.

Transport in humans occurs in the human circulatory system. The most important parts of the circulatory system are the heart, the lungs and the blood. In this practical, we focused mainly on the heart, the key organ in the circulation of blood, as it pumps blood to the rest of the body. By dissecting a real heart, not only were we able to gain new information, but we were also able to apply what we had previously learnt. As the real thing is very different from what we see on paper, it was harder to identify and label the parts of the heart, but it was also a new experience which helped us understand more about the topic. The labelling and dissection of the heart can be seen here.

Before the dissection.

After the dissection.

The heart was rubbery and smooth. Determining the bigger side of the heart allowed us to differentiate between the left and right atriums and ventricles. To find out which was the aorta, which was the pulmonary artery, the vein and the vena cava, we found out how deep the holes were and which chambers they led to first. One of the problems we came across was dissecting the heart itself. The chordae tendineae was especilly hard to cut. Other than that, though, the practical was more or less enjoyable.

References: Our Brains