Tissues-Lab by lanyuehua

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									              Anatomy & Physiology
              Unit 2: Cells & Histology                                                                 Lab

                                                                     Name________________________
                                                                      Date______________ Period____


                                                       Tissues Lab
              Directions:
                      This lab is broken down into three sections: Epithelial Tissue, Connective Tissue, and Muscle
              & Nerve Tissue. For each section, read the background and answer any questions before you come
              to class, then in class sketch the specimens listed under each sketch circle. For your sketches,
              include the total magnification under which you viewed the specimen and be very detailed in your
              sketch.


              Epithelial Tissue
              Background
              Functions of Epithelium
              Epithelium has two major functions: covering/lining
              and glandular:
                     Epithelial tissue covers body structures or
              lines body spaces. One side of the epithelium is free
              (not attached) because it either faces outward (skin)
              or inward (lining). The other side of the epithelium is
              called the basement membrane and is attached to
              underlying connective tissue. Epithelia do not have
              their own blood supply; therefore, nutrients must
              diffuse through the basement membrane to reach
              the cells.
                     Epithelia performing a glandular function are part of glands. Exocrine
              glands secrete substances into ducts which then empty onto epithelial surfaces
              (e.g. sweat glands, mammary glands). Endocrine glands secrete substances which
              then diffuse into the bloodstream (e.g. islet cells of pancreas secreting insulin).

              Classification & Composition of Epithelium
              Epithelium is classified by the number of cell layers and the shape
              of the cells in the outer layer.
                     Number of Cell Layers
                     Simple – only one cell layer.
Pseudostratified
                     Stratified – more than one cell layer.
                     Pseudostratified – “false stratified”. Nuclei have separated
                     into two layers due to cellular compaction.



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Anatomy & Physiology
Unit 2: Cells & Histology                                                       Lab

       Cell Shapes
       Squamous – like scales, wider than they are tall
       Cuboidal - ~cube-shaped, tall as they are wide, may be more
       rounded than square
       Columnar – column-like cells, taller than they are wide
       Transitional – cells that can change shape as needed, usually
       stretch or compress (always stratified)




       Miscellaneous Classification
       Epithelium can have some other unique characteristics that help us
       classify their types.
       Ciliated – cilia project along a cell’s free surface serving to propel
       material along the epithelial surface.
       Non-ciliated – cells lacking cilia
       Keratinized – some cell layers in stratified squamous tissues will be
       dead and filled with keratin (tough, waterproof material); no nuclei
       will be in these cells.
       Non-keratinized – cell layers without keratinized cells; will see
       nuclei in the squamous cells along the free edge.

Locations of Epithelium
   Different types of epithelia are found in various locations of the body
depending on what functions they carry out.
    Simple squamous epithelium – lines blood vessels, alveoli (air sacs) of lungs,
      and other areas requiring thin membranes; diffusion or filtration of water,
      gases, and other materials
    Stratified squamous epithelium – outer part of skin and mucous linings of
      mouth, vagina, and esophagus; protective function, thus outer cells
      continually slough off and are replaced by underlying cells
    Simple cuboidal epithelium - in secreting organs like glands and kidney
      tubules; specializes in secretion, water reabsorption, and ion movement
    Simple columnar epithelium – linings specialized for absorption and secretion
      like reproductive tract, digestive tract, excretory ducts, and respiratory


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Anatomy & Physiology
Unit 2: Cells & Histology                                                              Lab

       tract; often contains goblet cells which produce and secrete mucus for the
       purposes of lubrication and protection (see picture of ciliated cells above)
      Ciliated pseudostratified epithelium – found in upper throat, upper
       respiratory tract, and parts of male urinary and reproductive tracts
       Transitional epithelium – able to stretch, so is found in areas dealing with
       large amounts of elastic stress such as the urinary bladder

Epithelium Sketches – for each of the following specimens, examine at least one example in a
prepared slide and sketch a portion of the specimen that has the representative characteristics of
that tissue type. You must include the total magnification under which you viewed the specimen.
Each sketch is worth 3 points.




Simple squamous epithelium (surface view)            Stratified squamous epithelium (keratinized)
Total magnification: ______                          Total magnification: ______




Stratified squamous epithelium (nonkeratinized)      Simple cuboidal epithelium
Total magnification: ______                          Total magnification: ______




Simple columnar epithelium                           Transitional epithelium
Total magnification: ______                          Total magnification: ______



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Anatomy & Physiology
Unit 2: Cells & Histology                                                  Lab




Ciliated pseudostratified epithelium         Specimen: __________________________
Total magnification: ______                  Total magnification: ______


Epithelium Review Questions
   1. A type of cell found in simple columnar and pseudostratified tissue that
      secretes mucus.

   2. One of two kinds of glands, it secretes substances onto epithelial surfaces.

   3. A cellular organelle, it is a projection that moves substances along the
      surface of a cell.

   4. A type of epithelial tissue especially well adapted to excessive stretching.

   5. Mucous membranes secrete this water-based protein solution.

   6. A tough, waterproof material found in the upper layers of some examples of
      stratified squamous epithelium.

   7. The type of epithelial tissue likely to be found forming glands.

   8. The type of epithelial tissue likely to be found on the palm of the hand.




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Anatomy & Physiology
Unit 2: Cells & Histology                                                    Lab

Connective Tissue
Background
Functions of Connective Tissue
   1. Enclose organs and separate organs and tissues from one another
   2. Connect tissues to each other
   3. Support and movement
   4. Storage of energy and minerals
   5. Cushion and insulation
   6. Transportation of gases, nutrients, enzymes, hormones, and immune cells
   7. Protection against toxins/tissue injury and protect underlying structures

Classification & Composition of Connective Tissue
      All connective tissue has large amounts of extracellular matrix (ECM or
matrix). The type of ECM present in a connective tissue is often used to classify
the type of connective tissue.

       Types of ECM
       Protein Fiber Matrix – contains a dominance of protein fibers. Collagen is a
       type of protein characterized by bundles of tough, flexible fibers that are
       whitish in color. Elastin is a protein that is stretchy, fibrous, and forms
       thick, single fibers in connective tissues. Elastin is yellowish in color. The
       following types of connective tissues have a protein fiber matrix:
            Fibrous connective tissue: Dense fibrous connective tissues
              have densely packed protein fibers (2 types). The alignment
              of the fibers can be categorized as either regular or
              irregular. Loose fibrous connective tissues have loosely
              packed protein fibers (1 type).
                 o Dense collagenous fibrous: mostly collagen fibers in
                     matrix; contains fibrocytes
                 o Dense elastic fibrous: mostly elastic fibers in matrix;
                      contains fibrocytes
                  o Areolar tissue: fibers are loosely packed; blood
                      vessels & nerves pass through it
              Adipose connective tissue: “fat tissue” stores fat for
               energy, support, insulation, and cushion in large vesicles
               (can push nucleus & organelles to cell membrane); modified form of
               areolar tissue with little matrix



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Anatomy & Physiology
Unit 2: Cells & Histology                                                       Lab

           Protein/Ground Substance Matrix – this ECM has some protein fibers,
           but a lot of non-fibrous protein and other substances. Cartilage and bone
           have protein/ground substance matrices.
            Cartilage: has a matrix of fibers and ground substance that gives it a
              rubbery quality. There are 3 types of cartilage:
                  o Hyaline cartilage: moderate amount of collagen in the matrix;
                     has chondrocytes (cartilage cells) in lacunae (“lakes” or holes);
                     the fetal skeleton is largely made of hyaline cartilage before
                     bone replaces it; this is the most common type of cartilage

                     o Fibrocartilage: has a lot of collagen in its matrix; looks
                       especially fibrous; more rigid, less rubbery consistency
                     o Elastic Cartilage: matrix contains elastin, making it stretch

               Bone: has a matrix of collagen fibers that are encrusted with mineral
                crystals – this is what makes it solid. There are 2 types of bone
                which are found together:
                   o Compact bone: forms large, dense pieces of bone matrix
                           Compact bone is formed in cylindrical units called osteons
                              (see below – a.k.a. Haversian systems). Each osteon has
                              multiple concentric layers of hard bony matrix. Each
                              layer is called a lamella (pl. lamellae). Osteocytes
                              (inactive bone cells) are trapped inside lacunae between
                              the lacunae. Osteocytes were once active cells called
                              osteoblasts which created the hard, bony matrix. Each
                              osteon has a central canal (or Haversian canal) which
                              contains blood vessels. These blood vessels deliver
                              nutrients to the osteocytes via canaliculi (“small canals”).




         Cancellous bone




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Anatomy & Physiology
Unit 2: Cells & Histology                                                     Lab

                   o Cancellous (spongy) bone: forms thin, narrow beams of hard
                     bone matrix in which red bone marrow can be supported
                     (generates red blood cells)
                         Cancellous bone has an open, lattice-like structure.
                           Structural beams are formed from thin plates of bone
                           matrix that have a scattering of trapped osteocytes
                           inside lacunae. These beams are called a trabeculae.
                           The spaces are filled with myeloid tissue which is really
                           red bone marrow.



           Fluid Matrix – this ECM is a water-based solution, giving it a fluid
           consistency.
            Blood: blood cells are suspended within the fluid plasma
              and can slide past one another freely. Red blood cells
              (RBCs), platelets, and larger white blood cells (WBCs)
              are all present in blood tissue. Blood transports and
              exchanges materials, serves in immune protection, helps
              regulate body temperature, and other functions.

Locations of Connective Tissue
      Different types of connective tissues are found in various locations of the
body depending on what functions they carry out.
       Dense collagenous connective tissue – tendons (connect muscle to bone),
         ligaments (connect bone to bone), dermis of skin, organ capsules
       Dense elastic connective tissue - arterial walls, vertebral ligaments,
         dorsal neck, vocal cords
       Loose (areolar) connective tissue - widely distributed, between glands,
         muscles, nerves, attaches skin to tissues, superficial layer of dermis
         (allows skin to be slid around or pulled from the underlying muscle)
       Adipose - Beneath the skin, in breasts, within bones, in loose connective
         tissues, around organs (kidneys and heart); found wherever areolar tissue
         is found
       Hyaline cartilage - costal cartilages of ribs, respiratory cartilage rings,
         nasal cartilages, bone ends, epiphyseal (growth) plates, embryonic
         skeleton, larynx, trachea
       Elastic cartilage - external ear (pinna), epiglottis, auditory tubes




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Anatomy & Physiology
Unit 2: Cells & Histology                                                               Lab

          Fibrocartilage - intervertebral disks, pubic symphysis, articulating
           cartilage of some joints (knee, TMJ)
          Compact bone – outsides of bones
          Spongy (cancellous) bone – insides of bones
          Blood - in blood vessels and heart, produced by red bone marrow, WBCs
           leave blood vessels and enter tissues

Connective Tissue Sketches – for each of the following specimens, examine at least one
example in a prepared slide and sketch a portion of the specimen that has the representative
characteristics of that tissue type. You must include the total magnification under which you
viewed the specimen. Each sketch is worth 3 points.




Dense fibrous (regular) connective tissue            Adipose tissue
Total magnification: ______                          Total magnification: ______




Dense fibrous (irregular) connective tissue          Hyaline cartilage
Total magnification: ______                          Total magnification: ______




Loose fibrous (areolar) tissue                       Fibrocartilage
Total magnification: ______                          Total magnification: ______



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Anatomy & Physiology
Unit 2: Cells & Histology                                                  Lab




Elastic cartilage                            Cancellous bone
Total magnification: ______                  Total magnification: ______




Compact bone                                 Blood smear
Total magnification: ______                  Total magnification: ______


Connective Tissue Review Questions
   1. What type of cartilage has a great deal of collagen in its matrix?

    2. What tissue type is actually modified areolar tissue?

    3. What tissue type stores lipid molecules?

    4. Which tissue type is composed of haversian systems?

    5. Which is the most common type of cartilage?

    6. Which tissue is strong and forms ligaments and tendons?

    7. Which type of tissue is associated with red bone marrow?

    8. Which type of tissue forms strong membranes?

    9. Which type of connective tissue forms disks between vertebrae?

    10. What type of tissue forms hard mineral trabeculae?



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Anatomy & Physiology
Unit 2: Cells & Histology                                               Lab

Muscle Tissue
Background
Functions of Muscle Tissue
   1. Body movement via muscle contraction; create overall body movements
   2. Posture maintenance with constant skeletal muscle tone
   3. Respiration via thoracic muscles
   4. Body heat production as heat is released as byproduct of skeletal muscles
   5. Communication: oral, written, body language
   6. Organ & vessel contraction (move/mix food & water in GI tract, excrete
      secretions, regulate blood flow)
   7. Heart beat (cardiac muscle contraction; propels blood to body)

Classification & Composition of Muscle Tissue
       All three types of muscle tissue have the
ability to contract. This allows a muscle organ to pull
with great force causing the skeleton to move or the
contents inside of a hollow organ to be squeezed. All
muscle tissues are composed of long, cylindrical cells
called muscle fibers. These are living cells, unlike
connective tissue fibers, which are nonliving protein
fibers.
     Skeletal muscle – skeletal muscle is striated (striped);
       is voluntary (you can consciously move it); the cells are
       long, cylindrical, and can have many nuclei per cell
       (nuclei are usually close to the cell membrane)
     Cardiac muscle – cardiac muscle is striated and
       involuntary (you do not have conscious control over it);
       the individual muscle fibers are branched allowing the
       cells to communicate with one another for coordinated
       contraction (think heart beat); the cells are joined
       end-to-end by intercalated disks. Cardiac muscle
       fibers are not tapered at the ends and have only a
       single nucleus per cell.
     Smooth muscle – smooth muscle is not striated; it is
       involuntary; the cells are long and thread-like; each
       smooth muscle cell has only one nucleus and is tapered
       at the ends.




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Anatomy & Physiology
Unit 2: Cells & Histology                                                               Lab

Locations of Muscle Tissue
     Different types of muscle tissues are found in various locations of the body
depending on what functions they carry out.
      Skeletal muscle – attached to bone (these are the muscles that you can
         make larger with weight lifting and those that move all of your bones)
      Cardiac muscle – found only in the heart walls
      Smooth muscle – in walls of hollow organs and tubes (e.g. digestive organs,
         blood vessels, and eyes)

Muscle Tissue Sketches – for each of the following specimens, examine at least one example
in a prepared slide and sketch a portion of the specimen that has the representative
characteristics of that tissue type. You must include the total magnification under which you
viewed the specimen. Each sketch is worth 3 points.




Skeletal muscle                                      Smooth muscle
Total magnification: ______                          Total magnification: ______




Cardiac muscle
Total magnification: ______


Muscle Tissue Review Questions
  1. A voluntary type of muscle tissue is
         a. Skeletal                                             d. Both a and b are correct
         b. Cardiac                                              e. Both a and c are correct
         c. Smooth




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Anatomy & Physiology
Unit 2: Cells & Histology                                                 Lab

   2. An involuntary muscle tissue is
         a. Skeletal                                   d. Both a and b are correct
         b. Cardiac                                    e. Both a and c are correct
         c. Smooth

   3. Which of these muscle tissues is striated?
        a. Skeletal                                    d. Both a and b are correct
        b. Cardiac                                     e. Both a and c are correct
        c. Smooth

   4. Which of these is most likely to be found in the wall of the urinary tract?
        a. Skeletal                                    c. Smooth
        b. Cardiac

   5. Cardiac muscle fibers are connected end-to-end by means of
         a. Velcro                                  c. Striations
         b. Intercalated disks                      d. Branching

   6. Which of these cells is likely to have multiple nuclei
        a. Skeletal muscle                              d. Both a and c are correct
        b. Cardiac muscle                               e. All three (a-c) are
        c. Smooth muscle                                    correct


Nervous Tissue
Background
Functions of Nervous Tissue
   1. Sensory Input - like touch, temperature, taste, smell, sound, blood pressure,
      body position
   2. Integration – sensory information is processed by brain and spinal cord
      which then generate responses (e.g. reaction, stored in memory, ignored)
   3. Homeostasis – nervous system detects, interprets, and responds to changes
      in internal/external conditions; therefore, activates/inhibits activities of
      other systems, thereby maintaining constant internal environment
   4. Mental Activity - consciousness, memory, thinking
   5. Muscle and Gland Control - muscle movement controlled by nervous system
      (controls major and minor body movements)




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Anatomy & Physiology
Unit 2: Cells & Histology                                                Lab

Classification & Composition of Nervous Tissue
        Nervous tissue is composed of a few different types of
cells, each with their own distinct structure and function. All cells
in nervous tissue work together to generate smooth communication
between the brain and the rest of the body. The nervous tissue
composes organs of the nervous system: brain, spinal cord, and
nerves. For now we’ll just focus on two types of cells in the
nervous system.
         Neurons - impulse-conducting cells; large cells with
          nucleated bodies and projections called axons and
           dendrites
          Neuroglia – cells that act to support neurons
           physiologically and physically; much smaller and numerous
           than neurons; there are several types of neuroglia (we’ll
           learn these later)




Locations of Nervous Tissue
       Nervous tissue is present in your brain, spinal
cord, and nerves.

Nervous Tissue Sketch




Nervous Tissue
Total magnification: ______


Nervous Tissue Review Questions
  1. What cell(s) is/are present in nervous tissue?

   2. What is the function of each type of cell in nervous tissue?



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