Levels of Organization. Anatomical Position

Transcription

1 Levels of Organization Anatomical Position A stance in which a person stands erect with the feet flat on the floor, arms at the sides, and the palms, face, and eyes facing forward. The body standing erect, facing forward, feet together. Toes pointed slightly apart, hands at side, palms face anteriorly and thumbs away from body Assume all anatomical descriptions refer to this position. Always refer to the patient! 1

2 Anatomical Terminology Relative Positions: 1. Terms of relative position are used to describe the location of a part relative to another part. 2. Terms of relative position include: superior, inferior, anterior, posterior, medial, lateral, proximal, distal, superficial (peripheral), and deep. Body Regions Axial Region: head, cervical (neck), and trunk (thoracic region and abdominal region) Appendicular region: upper and lower limbs. 2

3 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Dorsal body cavity Ventral body cavity Abdominopelvic cavity Cranial cavity Vertebral canal Spinal cord Thoracic cavity Diaphragm Abdominal cavity Pelvic cavity Diaphragm Mediastinum Pleural cavity Pericardial cavity Abdominal cavity Pelvic cavity Thoracic cavity Abdominopelvic cavity a. The dorsal cavity can be divided into the cranial cavity and vertebral canal. b. The ventral cavity is made up of a thoracic cavity and an abdominopelvic cavity, separated by the diaphragm. i. The mediastinum divides the thorax into right and left halves. ii. The abdominopelvic cavity can be divided into the abdominal cavity and the pelvic cavity. c. Smaller cavities within the head include the oral cavity, nasal cavity, orbital cavities, and middle ear cavities. 3

4 Body Sections: 1. A sagittal section divides the body into right and left portions. 2. A transverse section divides the body into superior and inferior portions. It is often called a cross section. 3. A Frontal section divides the body into anterior and posterior sections. Microscopes 4

5 Microscopes Interpreting tissue sections Histological sections (thin slices of the tissue); smears; spreads Artificially colored (stained) to show detail fixative Cut (microtome) Dehydrated (might occur with fixation stage) stained Review your planes and be sure you can see how to put a tissue back together! 5

6 Magnification = Increases the size of an object. Resolving Power = Clarity of an image Total Magnification = Ocular mag x Objective mag Light microscopy Compound light microscopes: Magnify up to 1,000x Uses transmitted light only Both ocular & objective lenses Need to use oil with the oil-immersion lens to reach maximum magnification The oil has the same refractive index as the glass of the slide, allowing light to continue through the oil and into the objective lens without changing its angle, which increases resolution, allowing increased magnification 6

7 Light Microscope = works by passing light through a specim A light microscope cannot resolve detail finer than 0.2 micrometers, 1 micrometer = 1/1000 mm Light microscopes Base Arm Using a light microscopes Basic rules : Always use two hands when moving your microscope. Use one hand to hold the arm and the other hand to support the base. NOTE: The scopes are heavy! Please get one microscope per pair of students Use only LENS PAPER and lens cleaner to clean the lenses Do not use tissues, paper towels, kimwipes, your shirt, etc. to clean the scope Even though these items may feel soft, they can scratch the lenses 7

8 Light microscopes Ocular lenses (2) Revolving nosepiece (turret) Objective lenses (3-4) Stage & stage clamp Iris diaphragm lever (to adjust amount of light) Condenser adjustment knob (on other side of scope; to adjust light intensity) Light microscopes Focus adjustment knobs: Coarse (outer) Fine (inner) Slide movement knobs On/off knob Calculating total magnification What magnifications do the lenses of our light microscopes have? Ocular lenses? Objective lenses? Scanning lens Low power lens High power lens Oil-immersion lens Note: never use the highest magnification objective lens without using oil! Total magnifications for each objective lens? 8

9 Focusing the light microscope Every time you focus or re-focus the scope, follow these steps: 1. Lowest power objective in place (4x = scanning). 2. With eyes away from oculars, raise stage (with slide in place) all the way up 3. Look into oculars and slowly lower stage with coarse focus knob until object comes into approximate focus Use fine focus knob to finish focusing 4. When in focus, switch to higher power 5. ONLY focus with FINE focus knob when at higher magnifications If you lose the object or lose focus, repeat the procedure from step 1 Handling the microscope Every time you put your microscope away, observe the following practices: Lowest power objective in place (4x = scanning) Stage all the way lowered (slide removed) Light off Cover on Microscope put away in the appropriately numbered cubby in the microscope cabinet Mitosis - Early Prophase and Late Prophase 9

10 Mitosis - Metaphase and Anaphase Telephase and Cytokinesis 10