Purpose: The purpose of this lab is to familiarize the student with the use of a compound microscope and the Gram Stain test. Students will review a brief video and slides to introduce the compound microscope. Students will also view a video about the Gram Stain procedure and then answer questions related to it.
If I look at the slides I will see where the cell wall is and what lies inside it and in the Gram Stain if I watch the video I will learn how to differentiate in bacteria’s.
1. Examine the following slides and identify the cell structures within. You may need to look at each slide several times in order to see each structure.
2. Do your best to sketch the cells and structures listed below. Label each feature answer the questions in your lab report. Lab Questions
Why are the chloroplasts traveling along the outer perimeter of the Elodea cell?
The chloroplasts are traveling along the outer perimeter of the Elodea cell to carry nutrients through the cells and make them into useful substances for the cell to utilize.
What is the typical size difference between animal cells and bacterial cells?
The typical size difference between animal cells and bacterial cells is that animal cells normally are significantly larger. Another difference is that bacterial cell contains a plasmid, against the chromosomes that animals possess.
Part B: The Gram Stain
This procedure is used to separate what two types of bacteria?
This separation is based on differences in what physical trait?
The separation is based on differences in the structure of the cell walls
What is the iodine used for in this staining technique?
The iodine in this staining technique is used after the crystal violet is applied. The iodine then affixes this and then a decolorizer is applied to take away the primary stain.
Why is it important to heat fix the bacteria prior to the staining procedure?