Lab 1: Animal Tissues

What is Required for Full Credit (26 pts):

• 1. (12 pts) Complete the procedures below.

  2. (14 pts) Complete and submit the Lab Report 1a.

Materials

• • Frog skin epithelial tissue (ectoderm)

  • Frog skeletal muscle tissue

  • Frog hyaline cartilage connective tissue (mesoderm)

  • Frog spinal cord multipolar motor neurons, nerve tissue

  • Mesentery simple squamous mesothelium

  • Necturus intestine simple columnar epithelium (endoderm)

Procedure

• 1. Frog skin epithelial tissue (ectoderm)

     • Determine the average size of a frog skin epithelial cell and record your results.

     • At high power, notice things like cell shape, compactness, size of nucleus relative to cell size

     • Draw a few cells at 40x level.

  2. Frog skeletal muscle tissue

     • At 4x, note the degree of compactness compared to the skin epithelial tissue.

     • At 10x:

       • How are the cells different from those of the epithelial tissue?

       • What are the dark purple, flattened spots?

     • At 40x:

       • Notice the faint, many vertical "lines" among the tissues

         • These are the sarcomeres (in relation to the muscle contraction theory)

       • Note the cell shape, compactness, size of nucleus relative to cell size

     • Draw a few cells at 40x level

  3. Frog hyaline cartilage connective tissue (mesoderm)

     • At 4x:

       • Note the pink-stained muscle tissue

       • The cartilage is the light brown, thin, long section of cells

     • At 10x:

       • Note that the cells seem to be surrounded by cartiliage

     • At 40x:

       • Note the cell shape, compactness, size of nucleus relative to cell size

     • Draw a few cells at 40x level

  4. Frog spinal cord multipolar motor neurons, nerve tissue

     • At 4x:

       • Note the pink-stained material is muscle

       • The dark purple-stained material are the nerves. Since these are motor neurons, we would expect them to be imbedded in muscle, right?

     • At 10x

       • See if you can focus on a single cell body and observe dendrites emerging from the cell body.

       • Note the cell shape, compactness, size of nucleus relative to cell size

       • Draw a nerve cell at 10x level

     • At 40x

       • Observe whatever you want, if there is time

  5. Mesentery simple squamous mesothelium

     • At 10x

       • Which tissues so far examined look most similar to this one?

     • At 40x

       • Determine an average size of one of these cells and record your results.

       • Note the cell shape, compactness, size of nucleus relative to cell size

       • Draw a few cells at the 40x level

  6. Necturus intestine simple columnar epithelium (endoderm)

     • At 4x:

       • Note the cells located in the "fingers" extending to the center of the instestine

     • At 10x:

       • Note the cell shape, compactness, size of nucleus relative to cell size

     • At 40x:

       • Draw a few cells at 40x level

       • What do you suppose are the "empty white holes" in some of the cells?