BIO 141 Lab 1: Biology Lab Policies & Microscopy Review PDF
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Tidewater Community College - Virginia Beach Campus
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These are lab policies and procedures for TCC Virginia Beach biology labs, and microscope use instructions for BIO 141 Students.
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BIOLOGY LAB POLICIES TCC – VIRGINIA BEACH To maintain continuity and order, the Biology Department has established the following laboratory procedures to be followed by all students attending biology labs at TCC-Virginia Beach. It is important that you practice...
BIOLOGY LAB POLICIES TCC – VIRGINIA BEACH To maintain continuity and order, the Biology Department has established the following laboratory procedures to be followed by all students attending biology labs at TCC-Virginia Beach. It is important that you practice the following procedures, during scheduled labs and open study, without exception!! 1. NO FOOD OR BEVERAGE OF ANY TYPE IS ALLOWED IN THE LAB ROOM AT ANY TIME! Stow them in the cubbies near the entrance and eat or drink them outside the lab room. 2. Bring only the materials you will need to lab; space is limited and excess clutter should be avoided. Put all book bags and excess books/materials in the cubbies near the entrance. 3. Be familiar with the location of all lab safety equipment: first aid kit, fire extinguisher, eye-wash station and emergency shower. 4. Students are expected to leave their lab areas clean and organized when their work in the lab is complete. Put all models and specimens back in their proper places when done. 5. Students are NOT permitted to remove any materials from the lab; any such removal, even from one lab to another, is considered THEFT and may result in failure of the lab course by the offending student. Additionally, if materials disappear from any lab room, that lab room will be closed to open study. 6. Do not label models with tape, markers or any other materials. 7. Students will wear gloves during dissections; gloves will be provided by the student. 8. Students are expected to take full advantage of their designated lab time and not get in the habit of rushing to get out early. Additional open-lab study time is designed to supplement, not replace, regularly scheduled lab sessions. Refer to the lab schedule for open study times. 9. Open study time is designed for study, not socializing; be courteous to other students who are working in the labs. Under no circumstances will music be played in the lab rooms. 10. Students are NOT permitted to work in the labs when another class is in session. 11. Students are only allowed to study in lab rooms for which they are taking classes. 12. Students must sign in and out of all biology labs except during their regularly scheduled class. 13. Children are NOT allowed in the lab rooms at any time. This is for their benefit and safety, as well as the benefit of other students that may be studying in the lab. 14. CHEATING in any form will not be tolerated. Students found cheating will forfeit all previous grades received in their lab class and receive a final lab grade of “0”. 15. The biology labs open at 9:00 AM and close promptly at 9:00 PM Monday-Thursday (8:00 PM during the summer semester) and 4:00 PM on Fridays unless a lab section is scheduled outside of those times. Open study is available during those times, as long as a lab section isn’t scheduled; open study times are posted outside of each lab room. Labs are not open on the weekends or holidays. 16. When in doubt about anything, ask your instructor or an instructional assistant before proceeding. SIGN THE COPY OF THIS DOCUMENT PROVIDED BY YOUR INSTRUCTOR AND RETURN IT TO YOUR INSTRUCTOR By signing, you acknowledge that: - You will adhere to the rules of the Biology Lab at all times. - That you will follow instructions of any TCC biology instructor during open study times. - That failure to adhere to the lab policies may be cause for: a. Dismissal from tha lab for that particular session. b. Loss of assignment, quiz or practical points, as determined by your lab instructor. c. Dismissal from the lab for the remainder of the semester. BIO 141 LAB 1: TERMINOLOGY & MICROSCOPY REVIEW OBJECTIVES 1. Define anatomical terms and apply them. 2. Identify body cavities and abdominopelvic quadrants and regions. 3. Identify parts of the compound light microscope. 4. Demonstrate the proper use and stowage of the microscopes. MATERIALS Diagrams (refer to your textbook) Torso models Compound light microscope Microscope slides (assorted) EXERCISE ONE - TERMINOLOGY Terminology is an important part of Anatomy & Physiology; its proper use allows for better understanding and association of the human body and its component parts. Activity 1: Directional Terms Define and apply the following terms. TERM DEFINITION Superior Above Inferior Below Dorsal Spinal side (or towards the spinal side) Ventral Abdominal side (or towards the abdominal side) Anterior In front of Posterior Behind Medial Towards the midline Lateral Away from the midline (left or right) Proximal Towards the point of attachment or origin Distal Away from the point of attachment or origin Superficial At or towards the surface Deep Away form or below the surface Also be able to distinguish between anterior & ventral and posterior & dorsal; they are basically interchangeable in humans, but not in four-legged animals. Activity 2: Anatomical Regions Regional terms identify specific areas of the body. Define the following regional terms* and identify them on diagrams; refer to the appropriate textbook figures. TERM DEFINITION TERM DEFINITION Cephalic Head Axillary Armpit Orbital Eye socket Brachial Upper arm Mental Chin Antecubital Front of the elbow Cervical Neck Antebrachial Forearm Thoracic Chest Carpal Wrist Sternal Center of the chest Palmar Palm Abdominal Belly Digital Fingers or toes Inguinal Groin Femoral Thigh Pubic Above the genitals Patellar Knww Vertebral Spinal column Popliteal Back of the knee Lumbar Lower back Tarsal Back part of the foot Gluteal Buttock Pedal Foot Coxal Hip Plantar Sole of the foot Calcaneal Heel of the foot * Your lab instructor may require additional anatomical regions Activity 3: Body Planes Body planes represent how an anatomnical structure is viewed. Identify the following body planes on diagrams; refer to the appropriate figure in your textbook. PLANE DESCRIPTION Frontal (or coronal) Divides the front portion from the back portion Midsagittal (or median) Divides the left side from the right side Transverse Divides the superior portion from the inferior portion Activity 4: Body Cavities Cavities are spaces within the body. There are two major body cavities – the vental cavity and the dorsal cavity. Both of these cavities are further divided into smaller cavities. Identify the following body cavities on diagrams; refer to the appropriate figures in your textbook. Also be able to locate them on the torso model. DORSAL BODY CAVITY VENTRAL BODY CAVITY Cranial cavity Thoracic cavity Vertebral (or spinal) cavity - Pleural cavities - Mediastinum - Pedricardial cavity Abdominopelvic cavity - Abdominal cavity - Pelvic cavity Activity 5: Abdominopelvic Quadrants and Regions The abdominal cavity is divided into four quadrants. While this is not a true physical division, it does allow for better reference in a very busy area of the body (due to the large number of organs in the abdominopelvic cavity). For further specificity, the abdominopelvic cavity can also be divided into nine regions. Identify the four quadrants and nine regions of the abdominopelvic cavity on diagrams; refer to the appropriate figures in your textbook. EXERCISE TWO - MICROSCOPY Proper use of the microscopes should be mastered on an individual basis, as you will be using the microscope throughout the semester (and on the midterm practical). While several microscopes are available for observation of microscopic organisms and structures, the compound light microscope is considered to be the workhorse of most biology labs. Your light microscope, when used properly, will allow you to identify specimens that would be invisible to the naked eye, as well as examine structural details of those specimens. The compound light microscope uses a series of lenses to magnify the image of a thin specimen; these specimens are often stained to increase their contrast and provide a better image. Some important terms associated with the microscope that you should famiar with are: a. Working distance: The distance between the objective lens in use and the specimen. b. Field-of-view: The viewing area seen when looking through the ocular lenses. c. Depth-of-focus: The ability to focus on an entrie speciemen at one time. d. Parfocal: The ability of a microscope to stay in rough focus as magnification changes. e. Contrast: The ability to distinguish between light and dark areas of a specimen. As with any piece of equipment, proper use of the microscope makes for more efficient, as well as more enjoyable, viewing of specimens. The microscope typically works best at low magnification, since your working distance, field-of-view, and depth of focus are all greatest at low power. All of these factors, as well as light intensity, decrease as magnification increases. Therefore, you'll use your microscope more efficiently if you follow these procedures: 1. Always start to focus on your specimen at low magnification, using the coarse focus knob first; once the specimen is in view and the image is as clear as you can get it using coarse focus, then use fine focus to obtain a crisp image. You shouldn’t turn the fine focus knob more than one revolution. At this magnification, your working distance and field of view are maximal, and it is relatively easy to obtain a clear focus. 2. If higher magnifications are necessary, first center your specimen in the field-of-view using the mechanical stage controls, then increase magnification as appropriate. Due to parfocal, the microscope should stay in rough focus as you change magnification, and only fine adjustments to focus will need to be made. 3. As you increase magnification, light adjustment may be necessary. The light intensity knob provides for major changes in light intensity, while the aperture iris diaphragm ring can be used to further reduce light and often make detail stand out when nearly closed. 4. As a rule, use the lowest magnification necessary to make your observations; large specimens are usually best viewed at LOW power, while individual cells look best at medium or high power. 5. NEVER USE COARSE FOCUS AT HIGH POWER; with a minimal working distance, you risk damaging the specimen and the objective lens! 6. Use lens paper ONLY to clean your microscope's lenses. If you move the specimen and what you're observing doesn't move, then you have dirt on either the condensor or one of the lenses. Activity 1: Identify Parts of the Compound Light Microscope Obtain a compound light microscope from the storage cabinet; visually identify all microscope parts listed on the following photograph. Activity 2: Calculate Total Magnification Your compound light microscope provides three objective lenses for observations at various magnifications, usually referred to as low, medium and high power. You can calculate the total magnification that the microscope is set at by multiplying the magnification power of the eyepieces (10x) by the magnification power of the objective lens in position (pointing down towards the specimen). Calculate the actual value for each power: OBJECTIVE LENS OBJECTIVE POWER TOTAL MAGNIFICATION Low power Medium power High power Activity 3: Function of Compound Light Microscope Parts Identify the function of all parts listed in this table. MICROSCOPE PART FUNCTION Ocular lenses (eyepieces)(2) Magnify the image (10x) Objective lenses (3) Magnify the image (4x, 10x, 40x) Revolving nosepiece Rotates objective lenses into viewing position Stage Supports the specimen for viewing Specimen holder Holds the slide firmly in place Light switch Turns the light source on/off Light source Provides light to illuminate the specimen Light intensity knob Adjusts intensity of the light source Condensor Focuses light on the specimen Iris diaphragm ring Controls the amount of light entering the aperture Coarse focus knob Rapidly brings the specimen into focus (use first at low power) Fine focus knob Slowly brings the specimen into final focus Mechanical stage controls (2) Move the slide forward & back, left & right on the stage Activity 4: Proper Use of the Compound Light Microscope Using slide specimens available, practice using your microscope properly; you will be required to set up and focus several specimens on the Practical Exam. Observe the effect of changes in magnification on field-of-view, working distance, depth-of-focus, and illumination. Take your turn using the microscope – DO NOT RELY ON YOUR LAB PARTNER TO DO ALL THE WORK FOR YOU! Steps for optimal light microscopy: 1. Place the specimen snugly in the slide holder; set the low power objective into position and turn the light on (set light intensity to center scale). 2. Using the mechanical stage controls, center the specimen under the low power objective. 3. While looking through one or both oculars, turn the coarse focus knob until the specimen is focused as clearly as possible. 4. Using the fine focus knob, make slight adjustments to increase the clarity of view. 5. Using the mechanical stage controls, center the area of the specimen you wish to examine further in center of the field-of-view. 6. Increase magnification and adjust lighting accordingly; never use coarse focus at high power magnification. Remember, the general rule of thumb is to use the lowest magnification necessary to identify what you need to see. Also make sure your light level is not too high; low light is typically better than high light levels. YOU ARE NOT RESPONSIBLE FOR ANY OF THE SPECIMENS YOU OBSERVE TODAY; THEY ARE SIMPLY SOMETHING TO LOOK AT TO LEARN PROPER USE OF THE MICROSCOPE. Activity 5: Stowing the Compound Light Microscope To ensure long-life and prevent damage, you must properly stow the compound light microscope after use. Steps for proper stowage of the compound light microscope: 1. Turn off the light. 2. Remove the specimen slide; return it to the appropriate slide box. 3. Make sure all microscope surfaces are clean and dry. 4. Lower the stage completely, using the coarse focus knob. 5. Turn the revolving nosepiece to position the low power objective in place. 6. Grasping the plug, unplug the power cord. Wrap the power cord around your hand to form a bundle; loop the plug through the bundle a couple of times. 7. Place the bundled cord on the stage; raise the stage all the way, using the coarse focus knob. Do not wrap the cord around the frame of the microscope. 8. Place the dust cover over the microscope. 9. Carrying the microscope with two hands (one on the base, the other on the frame), place the microscope in the storage cubicle with the number that corresponds to the number on the back of the microscope. Microscopes should be placed side-ways, six per shelf.