A&P 1 Cellular Anatomy, Division & Mitosis In-lab Guide Lab Exercises. In this "Lab Exercise", we will be looking at cellular anatomy and mitosis.

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1 A&P 1 Cellular Anatomy, Division & Mitosis In-lab Guide Lab Exercises In this "Lab Exercise", we will be looking at cellular anatomy and mitosis. Before trying to do these steps, we should have read the pertinent sections in the lab and/or lecture book, and watched any online videos my instructor has available. The Steps found in this "Lab Exercise Guide" do NOT have to be done in the order they are found. However, please do all the questions within a step before moving on to another step! Please Note: there is a section at the end of this document entitled Exercises to be done in Lab, Learning Lab, or Home which do not have to be completed in lab if you run out of time. But make sure you do them!

2 Model #1 Step 1. Identify the organelles on several models, and look at cell slides #1 The Models in lab Warning! Not all organelles can be seen on all models! There are 3 different cell models in the room. Find as many organelles, and other cellular structures, as you can on each! Use your wordlist as a guide. Not all organelles can be seen on all models! And they can look different on different models! You never know which model will be on the exam, so know them all! Q1. There are 2 Golgi bodies on Model #1 AND #2, but they look really different from each other. Why? Model #2 Q2. All of the models show mitochondria in 2 different ways. What is the difference? MAKE SURE YOU SEE BOTH on the images. Q3. Both "Secretory vesicles" and "Lysosomes" are just small sacs. How can you consistently tell them apart WITHOUT using color, which is NOT consistent? (HINT: look where the secretory vesicles are going!) Q4. Are there any other organelles that are simply "small sacs", and might be confusing? Q5. What is the difference between saying "nucleus" and "nuclei"? Q6. What is the difference between saying "nucleus" and "nucleolus"? Q7. What is the difference between saying "nucleolus" and "nucleoli"? Model #3

3 #2 Look at the slides of a basic cell, and ID the basic parts: Now, go to the Microscope Station. There are 5 slides: simple squamous tissue (low power), simple squamous (high power), blood cells, simple columnar, and sperm. Look at the first slide, and at the image entitled "image 1", while reading the following: Not much can be seen on a simple light microscope in the way of organelles. The plasma membrane stains dark, as does the nuclear envelope. This is because of the large amount of protein. The cytoplasm looks "grainy", although individual organelles cannot be identified. Nucleoli stain as little dark specks in the nucleus. Image 1 A little later, we will look at the other slides, which show us different cell shapes.

4 Step 2. Study Mitosis models and slides Know the stages of the life cycle and cellular structure found on the word list. Put the models in order, starting with interphase. Make sure you can do this, along with the questions on the next page: Identify a cell in Interphase (models and slides) Identify a Nucleus (models and slides) Identify Chromatin (model of Interphase, and image) Identify Chromosomes (models, images and slides) Identify Sister Chromatids and Centromere (models and image) Identify Spindle Fibers (models and slides) Identify Centrioles (models only!) Identify a Cell Equator Identify a cleavage furrow (models and slides) Define G phase, S phase, mitosis, cytokinesis Identify a cell in Prophase (models and slides) Identify a cell in Metaphase (models and slides) Identify a cell in Anaphase (models and slides) Identify a cell in Telophase (models and slides)

5 See if you can answer these: Q8. What do we call the process of splitting the cell? (HINT: it is not mitosis!). Q9. Discuss in your group: Interphase is not a part of mitosis. Why not? Start by defining mitosis. Make sure you understand the answer. Q10. Three of these cellular structures are present during mitosis. Which are they? Cross off the ones that are not. (HINT: the images in your text book and lab book clearly show you the answer) Nuclear membrane Nucleoli Spindle Fibbers Chromosomes Chromatin Mitochondria Centrioles Ribosomes RER Q11. Name the stages of mitosis in order. Q12. Visually seeing a "cleavage furrow" means that you are seeing which process? Pick from the list: Mitosis Metaphase Protein Synthesis Duplication of the genetic material Interphase Cytokinesis Q13. How do you know when mitosis is over? Pick from the list: a. The nucleus disappears, the spindle fibers form, and chromosomes are obvious for the first time. b. Cytokinesis begins, so you can see a cleavage furrow. c. The nucleus and nucleoli re-appear. d. Chromosomes align themselves in the center of the cell. e. Chromatids are separating from each other. Q14. OK...now, go back to the previous question, and write next to the "other answers" the stage of mitosis they are describing.

6 Step 3. Identify cells and cell shapes under the microscope There is a station in the room with photographs of different types of cells. Go to that station and follow the instructions. Do not worry if you do not have time for this in lab. However, it does help you get ready for next week (Histology lab). NOTE: There is a copy of this exercise online, in case you want to study it at home, or in the Learning Lab.

7 Step 4. Exercises to be done in Lab, Learning Lab, or Home #1 Model Comparison Exercise This can be done at home or in Learning Lab. Below is a photograph of a cell model we do not have in lab. Some structures look really different than the models in lab. Follow the instructions. There is no need to print out the image. Also Note: Not everything can be seen on this model! Be careful! You will notice that there is a link on that page that brings up more images for you to compare! Diagram of a cell model not seen in lab See if you can ID the following: Easy to find, because they look like the models in lab: Plasma membrane Nucleoli RER Cytoplasm Ribosomes SER Nuclear envelope Mitochondria Centrioles Hard to find, because they look different: Golgi apparatus Secretory vesicles Lysosome Also, you can click on the link below to bring up a Google search and compare various models and images: Google Search Cell Anatomy Unlabeled

8 #2 Study Organelle function This can be done at home or in Learning Lab. On the lab guide webpage, near the wordlist, I gave you a link to download a blank copy of the organelle table found in the Pre-lab guide. Fill it out from memory. If you can t, re-do the process until you can! Make sure you get each function narrowed down to a 3 or 4 word description.