Histology Lab Notebook (ELN 5)
Instructions
- Lab notebooks are completed digitally using the Crowdmark platform. You will submit your lab notebook before the end of the lab time.
- The amount of work expected for these lab notebooks is reflective of the time available! Labs run for 3 hours – we have therefore designed the lab activities and the lab notebook prompts in such a way that they will be able to be completed within the 3 hour window of provided time.
- It is strongly advised that you read the lab outline BEFORE the lab starts to ensure you will be prepared to manage your time effectively and complete all protocols during the lab.
- This lab notebook will be completed as PAIRS
- This lab notebook (and completion of the lab) is pass/fail
- Assignment Deadlines
- Policies on Submitting Work, Absences and Missed Work
- Specifications guidelines for Electronic Lab Notebooks
Part 1: Pre-lab
- What is the purpose of today’s lab activity?
- What protocols will you be completing in the lab?
- Are there any safety precautions to be aware of before starting?
Part 2: Raw Data
- upload one representative image of each age of mouse tissue (two images total)
- the images should be in .jpg/.jpeg or .png format (.png, .jpg, and .pdf are the accepted file types for this format of Crowdmark question)
- the images should be annotated with a scale bar (you will follow the ImageJ instructions to add the scale bar to each image using the micrometer image provided to you at the same magnification)
- the image should be clear and in focus, and should show the region of the mouse tissue that contains the epidermis and the dermis layers
- these images do not need to be formal figures with captions – the scale bar is the only modification you will be making to these images
Part 3: Predictions
- Based on the images you captured today, do you have a hypothesis about what trend you will observe in the thickness of the epidermis and dermis layers of the skin tissues as mice age? Why do you think this might be the case? Answer this based on your existing knowledge/memory of the lecture – no need to dig into scientific literature or provide any references for this question response.
Part 4: Graph
- Prepare a graph comparing the mean thickness of the dermis and epidermis of skin samples from mice of the two different ages (5-day and 2-year).
- Using ImageJ, measure the thickness of the epidermis and dermis from the two ROI (i.e. two images you captured) in each of the two tissue samples (5-day and 2-year mouse skin). You will select five (5) locations within each of the images that you captured during the lab per mouse age (i.e. 5 measurements in each image, 10 measurements total per tissue sample).
- Use the image of the stage micrometer at the same magnification as the corresponding mouse skin images to calibrate the scale in ImageJ before taking your measurements. Recall, the stage micrometer is a tiny ruler.
- After taking the measurements from the images, calculate the mean thickness and standard deviation of the dermis and epidermis for each mouse skin sample (5-day and 2-year) and construct your graph. Be sure to include error bars and follow the guidelines for graphs in the LRWG.
Part 5: Stained Slide
- Ensure you have placed your stained and coverslipped microscope slide in the drying booklets located near the fume hoods. Each student should stain their own slide, so your pair will have two slides in the drying booklet at the end of the activity.
- You should write your name and lab section clearly on the slide in pencil so your TA can check completion of the activity.
- NOTE: We will bring your slides back out next week so you can have a peek at them under the microscopes and see how you did!