Bio Lab Test
Interphase
•Involves synthesis of chemicals and structures required for cell division. •DNA, RNA, and proteins are produced. •Important structures such as centrioles are manufactured. •The cells are recognized by the presence of a well defined nucleus comprised of chromatin, containing DNA and proteins surrounded by a nuclear membrane. •A prominent nucleolus or nucleoli may be present inside the nucleus. •The cell is engaged in metabolic activity and performing its prepare for mitosis. Chromosomes are not clearly discerned in the nucleus, although a dark spot called the nucleolus may be visible.
Tube (of the microscope)
(of the microscope) Connects the eyepiece to the objective lenses
Arm (of the microscope)
(of the microscope) Supports the tube and connects it to the base
Ocular Lens (of the microscope)
(of the microscope) the lens at the top that you look through. Usually 10X or 15X power.
Illuminator (of the microscope)
(of the microscope) A steady light source (110 volts) used in place of a mirror. The light source for the compound microscope. This is usually an incandescent light bulb which is located at the bottom of the compound microscope.
Condenser Lens (of the microscope)
(of the microscope) Lenses found after the illuminator but prior to the specimen. The condenser focuses the light passing through the specimen and into the objective lens.
Diaphragm or Iris (of the microscope)
(of the microscope) Many microscopes have a rotating disk under the stage. This diaphragm has different sized holes and adjusts to control the amount of light coming from the illuminator which enters the rest of the microscope through the condenser.
Stage (of the microscope)
(of the microscope) The flat platform where you place your slides. Stage clips hold the slides in place. The often movable platform which holds the specimen.
Base (of the microscope)
(of the microscope) The flat, bottom portion of the microscope used for support. It is attached to the arm and supports the rest of the microscope. The in-base illuminator and dimmer switch are located here.
How to Focus Your Microscope (of the microscope)
(of the microscope) The proper way to focus a microscope is to start with the lowest power objective lens first and while looking from the side, crank the lens down as close to the specimen as possible without touching it. Now, look through the eyepiece lens and focus upward only until the image is sharp.
Revolving Nosepiece (of the microscope)
(of the microscope) This is the part that holds two or more objective lenses and can be rotated to easily change power.
Objective Lenses (of the microscope)
(of the microscope) Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of 4X, 10X, 40X and 100X powers. The shortest lens is the lowest power, the longest one is the lens with the greatest power.
Fine Focus Knobs (of the microscope)
(of the microscope) allow focusing on the fine details of the specimen
Body Tube (of the microscope)
(of the microscope) located on the top end of the arm about the stage. At the bottom of it is found the revolving nosepiece and the objective lenses. At the top are the ocular lenses. The body tube directs light from the objective lenses into the ocular lenses.
In-base Illuminator (of the microscope)
(of the microscope) the light source of the microscope is located in the base.
Illuminator Dimmer Switch (of the microscope)
(of the microscope) this controls the illuminator by turning it on or off. It also adjusts the amount of light put out by the illuminator.
Coarse Focus Knobs (of the microscope)
(of the microscope) used to focus the specimen and bring it into view
Abdominal cavity (structures in this cavity)
(these are located in what cavity?) digestive organs, major blood vessels, liver, spleen, kidneys
Mediastinum (structures in this cavity)
(these are located in what cavity?) heart, trachea, esophagus, thymus gland, major blood vessels attached to the heart
Thoracic cavity (structures in this cavity)
(these are located in what cavity?) lungs, heart
Pelvic cavity (structures in this cavity)
(these are located in what cavity?) the end of the digestive tract, internal reproductive organs, urinary bladder, ovaries, rectum, urethra, sacral arteries, vesicular pouch
Transitional epithelium
(tissue found in) bladder, ureters, urethra & urinary tract. Similar to stratified squamous. Multiple layers of rounded cells. Can be recognized by the large rounded epithelial cells lining the lumen
Simple Squamous epithelium
(tissue found in) blood vessels. Single layer of flat, scale-like cells
Simple Cuboidal epithelium
(tissue found in) kidney tubules, glandular ducts, ovaries, and the thyroid gland. Single layer of cells that are as tall as they are wide. Each cell has a spherical nucleus in the centre.
Pseudostratified Ciliated epithelium
(tissue found in) respiratory tract. Have cilia. Some epithelia give the false appearance of being stratified, but in effect consist of a single layer of irregular columnar cells, all in contact with the basal lamina.
Stratified epithelium
(tissue found in) skin and tongue. Multiple layers of flat cells. Cells flatten as the layers become more apical, though in their most basal layers the cells can be squamous, cuboidal or columnar.
Simple Columnar epithelium
(tissue found in) the lining of the stomach, intestines and gallbladder. Single layer of tall, elongated, cylinder , column-shaped cells. Their nuclei are elongated and are usually located near the base of the cells.
Adipose tissue or fat
(type of tissue) Cells are large, white, round, like cotton balls. 2 types- yellow and brown. Unique b/c it has little extracellular matrix. Where energy is stored. Serves as insulating tissue. Located in the deepest level of the skin, the subcutaneous layer, providing insulation from heat and cold.
Blood tissue
(type of tissue) Vascular connective tissue. Contains erythrocytes (red blood cells), leukocytes (white blood cells), and platelets (cell fragments) in a liquid matrix called plasma. Formed by hemopoietic tissue
Bone connective tissue
(type of tissue) Vascular- has a blood supply. Osseous. Osteocytes are found in the lacunae amidst a calcified matrix. The skeleton is built of this. The main store of calcium and phosphate. Has several metabolic functions especially in calcium homeostasis.
Dense connective tissue
(type of tissue) contains an abundance of protein fibers as well as fibroblasts. It forms structures such as tendons (attach muscle to bone) and ligaments (attach bone to bone). Avascular- no blood supply
Hyaline Cartilage
(type of tissue) costal cartilages of the ribs, trachea, and bronchi. Avascular- no blood supply. The cells of this tissue are chondrocytes- are small cells with an oval nucleus and one or two nucleoli. Found at the ends of bones, the nose, and the rings of the trachea. Consists of a slimy mass of a firm consistency, but of considerable elasticity and pearly bluish color. Its structure is relatively simple
PARAFOCAL
A microscope is parafocal if it can be changed form one objective to another and still have the image in focus. Most microscopes are parafocal when they are new and in good condition. They may lose this quality after prolonged use and mistreatment.
Why is lens paper used to clean the microscope lenses?
It has extremely fine, soft fibers. Other types of paper have coarser fibers that will gradually scratch the lenses causing them to become foggy and blurry.
Does the image of the letter remain rightside up or is the image altered in some way as it passes through the compound light microscope?
It is upside down and reversed/backwards because of a series of lenses and mirrors
If you move the slide to the right, which way does the image on the compound light microscope move?
Moves to the left
Total Magnification =
Power of ocular lens X Power of objective lens =
Cytokinesis
The final stage of the cell cycle, in which the cell's cytoplasm divides, distributing the organelles into each of the two new cells.
Prometaphase
The second stage of mitosis, in which discrete chromosomes consisting of identical sister chromatids appear, the nuclear envelope fragments, and the spindle microtubules attach to the kinetochores of the chromosomes.
OBJECTIVE LENSES
These lenses determine how many times the image of the specimen will be magnified. They collect the light coming from the specimen and magnify the image. Light is then directed through the body tube.
How does a Scanning electron microscope and a Transmission electron microscope differ from a compound light microscope?
They differ because they use electron beams as their illumination source and the specimens are stained with heavy metal ions.
STAGE
This is the flat surface attached to the arm which is used to place the slide of a specimen. It has a small opening in the center which allows the light beam from the illuminator to come through the specimen on the slide.
IMMERSON OIL
This is used with the oil immersion lens. Normally there is a layer of air between the specimen and the objective lens. Immerson oil is placed between the specimen and the oil immersion lens to prevent light scattering. Air scatters the light beam at high magnification powers which reduces the ability to focus and decreases the intensity of the light coming through the lens.
ARM
This portion of the microscope projects up from the base and supports the body tube and stage. It is also used to grasp the microscope when lifting or moving it.
Stereoscopic microscope
Used to view objects that are visible to the naked eye but are too small to see any detail. Maximum magnification is 20X.
What is used to clean immersion oil from the compound light microscope lenses and why?
Xylene - is a solvent used with lens paper to clean grease and oil from the lenses.
DUST COVER
a plastic or cloth cover placed over the microscope during storage. It protects the microscope from dust and dirt accumulation while being stored.
LENS PAPER
a special type of paper with extremely fine, soft fibers. It is used to clean the lenses. Other types of paper have coarser fibers that will gradually scratch the lenses causing them to become foggy and blurry.
FINE FOCUS KNOBS
allow focusing on the fine details of the specimen
INTERPUPILLARY ADJUSTMENT
allows adjustment of the distance between the ocular lenses to the distance between two eyes. It allows both eyes to see the image at the same time.
Transmission electron microscope
directs a beam of electrons through an ultra thin slice of a specimen to reveal its internal structure.
Prophase
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus and the dissolution of the nuclear envelope
STAGE CLIPS
hold the slide in place on the stage. They are associated with the slide mover knobs
REVOLVING NOSEPIECE
located at the bottom of the body tube and is attached to the objective lenses. Used to position one objective lens at a time above the light beam coming from the specimen
OCULAR LENSES
located at the top of the body tube, and receive the light beam from the body tube. They magnify the image and direct it to the eyes. Usually 10X lenses, but may be 5X or 15X
IRIS DIAPHRAM
located between the condenser lens and the illuminator. It regulates the amount of light reaching the slide and acts similarly to the iris of the eye which controls pupil size.
BODY TUBE
located on the top end of the arm about the stage. At the bottom of it is found the revolving nosepiece and the objective lenses. At the top are the ocular lenses. The body tube directs light from the objective lenses into the ocular lenses.
SLIDE MOVER KNOBS
move the slide clips & slide on the stage so one can scan the entire specimen.
RESOLVING POWER
the ability of a microscope to produce clear, sharp images which allow two small points to be seen as distinct objects rather than one blurred image. The higher the resolution of the microscope, the closer the two objects can be and still be identified as separate structures.
Telophase
the final stage of meiosis or mitosis, in which the separated chromosomes reach the opposite poles of the dividing cell and the nuclei of the daughter cells form around the two sets of chromosomes
BASE
the flat, bottom portion of the microscope. It is attached to the arm and supports the rest of the microscope. The in-base illuminator and dimmer switch are located in the base.
TOTAL MAGNIFICATION
the image which reaches the eyes has been magnified by two lenses. First the objective lens magnifies the image. This image is passed up through the body tube and magnified a second time by the ocular lenses. To determine how many times the image that is seen has been magnified use: Total Magnification = (Power of objective lens) X (Power of ocular lens)
IRIS DIAPHRAM LEVER
the lever used to open and close the iris diaphragm
IN-BASE ILLUMINATOR
the light source of the microscope is located in the base.
Metaphase
the stage in mitosis or meiosis in which the duplicated chromosomes line up along the equatorial plate of the spindle
Anaphase
the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles
ILLUMINATOR DIMMER SWITCH
this controls the illuminator by turning it on or off. It also adjusts the amount of light put out by the illuminator.
XYLENE
this is a solvent used with lens paper to clean grease and oil from the lenses. Other solvents may damage the lenses or materials that anchor them in place such as the lens seals.
CONDENSER LENS
this lens is located between the stage and the illuminator. Its function is to focus the light beam on the specimen.
COARSE FOCUS LENS
used to focus the specimen and bring it into view
Scanning electron microscope
used to observe surface structures and molecules of a specimen.
Compound light microscope
uses light beams to view a specimen. Has different lenses which allow viewing of the specimen at different powers of magnification. Max magnification is 1,500X.