Tag Archives: practical

Student Investigations in Biology

Unit 4: Area of Study 3 in the VCE Biology Study Design provides details of the practical investigation that students are required to complete, worth one third of the school assessed coursework for Semester 2.

On the completion of this unit the student should be able to design and undertake a practical investigation related to cellular processes and/or biological change and continuity over time, and present methodologies, findings and conclusions in a scientific poster.

There are a great number of practical investigations suitable for students, however, careful consideration of the materials and equipment available and the time taken to achieve useful results is prudent. The following resources provide lists of practical investigations that may be of interest:

When you have decided which investigation you are interested in and after discussion with your teacher, submit a proposal that includes the following information:

  • Your name
  • Title (up to ten words about the experiment)
  • Hypothesis (what exactly are you testing?)
  • Materials required (consumables)
  • Equipment required (experimental tools, glassware etc)
  • Estimated time for conducting the experiment and collecting results
  • References (Where did you get the idea from and what other information do you need?)

Thursday 3rd March – Work to go on with

Agar for diffusion experiment

This is a picture of the experiment “Shaping Up – the relationship between shape and diffusion”. It shows the agar stained with phenolphthalein indicator, which turns clear in acid. When the different size and shaped agar blocks are placed in an acid solution, the aicd diffuses into the jelly, causing to change from pink to clear. The time taken for a block to totally decolourise is a measure of the rate of diffusion of acid into the jelly. We will be doing this experiment on Friday, during periods 1 and 2.

Please make sure you have read all of chapters 1 and 2 and finished all the relevant Chapter Review questions. If you have finished this work, you can start reading chapter 3 “Composition of Cells” (pages 52 to 73). This chapter is designed for you to develop a knowledge and understanding of the composition of cells, understand the relationship between the nature of various substances found in cells and the functions they perform in those cells and learn more about inputs and outputs, enzymes  and biochemical processes.

Rat Dissection

Source: Biology Online

This Wednesday afternoon we will be dissecting laboratory rats, which are specially bred for scientific purposes. This practical exercise is optional, but an excellent way to gain scientific skills of careful observation, identification of body parts and an understanding of the structure and function of the digestive system of mammals. If you plan to continue your science education at university, you will find this a valuable introduction to laboratory dissections. Make sure you read the practical instructions thoroughly, work slowly and carefully and document your progress with video or a digital camera. Remember that ‘dissection’ does not mean ‘to cut up’, it means ‘to expose to view’ – once something has been cut, it can’t be undone, so know what organ or tissue you are cutting and why.

Rat Dissection – Part 1: Exposing the Abdomen

Rat Dissection – Part 2: The Digestive System (Warning – graphic images)

Rat Dissection – Part 3: Identifying the organs of digestion.

What did you learn about dissection and the digestive system of a mammal? Compared to the length of the rat, how long was it’s alimentary canal? What was the difference in the wall of the stomach and the small intestine? What did you notice about the contents of the alimentary canal as they moved towards the rectum? What surprised you most about the inside of a rat?

Procedure for rat dissection.

Classification of the rat and glossary of terms (dorsal, ventral, thoracic etc.)

Check out Miss Baker’s Biology Blog, “Extreme Biology” for a video of a dogfish shark dissection.