viewing an onion cell through the microscopeWrite up a mini report for the experimentHeading/titlethe purposeequipmentrisk assessmentmethodWrite up a risk assessment for the practical

Homework:Watch videos and prepare for the practical on Monday.Practical - making a wet mount slide and and viewing an onion cell through the microscopeWrite up a mini report for the experimentHeading/titlethe purposeequipmentrisk assessmentmethodWrite up a risk assessment for the practical

A student prepared some onion cells. The student viewed the onion cells using a light microscope. This is the method used. 1. Cut an onion into pieces using a sharp knife. 2. Peel off a thin layer of onion epidermis from one piece of onion. 3. Place the onion epidermis onto a microscope slide in a single flat layer. 4. Add three drops of iodine solution. 5. Slowly lower a cover slip at an angle onto the onion epidermis. 6. Place the slide on the stage of the microscope. 4. Page 6 of 16Sugars absorbed via active transport would show a decrease in aborption rate where there is no respiration occuring as it needs energy to carry out active transport and from the table we can see that the sugars glucose and galactose both significantly decreased whichi informs us that those two sugards can be absorbed by active transportBecause every single sugar got absorbed which informs us that some form of diffusionhas taken place(a) The table below shows a risk assessment for this experiment. Complete the table.HazardRiskPlan to minimise risk Iodine solution is an irritant May cause allergic reaction or skin rashSharp knife(2) (b) Give a reason for each of the following steps in the method. A thin layer of onion epidermis is used. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Iodine solution is added to the onion epidermis. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ The cover slip is lowered onto the onion epidermis at an angle. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (3) Page 7 of 16Figure 1 shows what the student saw under the microscope at a magnification of ×400. Figure 1 (c) The length of cell Z in Figure 1 is 4.8 cm. Calculate the real length of cell Z. Give your answer in micrometres (μm). ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Real length of cell Z = _______________μm (5) Page 8 of 16Figure 2 shows the student’s drawing of Figure 1. Figure 2 (d) Give two ways the student could improve the drawing in Figure 2. 1 _________________________________________________________________ ___________________________________________________________________ 2 _________________________________________________________________ ___________________________________________________________________ (2) (e) Onion cells can be seen using an electron microscope. Give two ways onion cells would look different when seen using an electron microscope. 1 _________________________________________________________________ ___________________________________________________________________ 2 _________________________________________________________________ ___________________________________________________________________ (2) (Total 14 marks)

Give a step-by-step procedure for preparing a wet mount slide to view onion cells under a light microscope.

Sasha is using the microscope below to look at onion cells. Once she has the onion cells mostly in focus, what does she use to make the image even clearer?

I thought I did well in this sample because I showed examples of what was needed for this experiment and demonstrated why these materials can be a risk hazard. I could’ve improved my work by __________. This helped me in my summative task because it deepened my understanding of how to identify and classify organisms.