Download Penuntun praktikum histology – cell and genetics

Lab activity manual – cell and genetics - Histology
In this lab activity, you have to examine histological specimens under the microscope.
A microscope has 2 kinds of lenses, the ocular and the objective lenses. The ocular lens is
located at the eye piece (the upper part). For new microscopes there is only one ocular
lens (10X), but for older ones, a microscope has 2 ocular lenses (5X and 10X), which are
interchangeable. The objective lenses are located at the lower part of the eye piece,
screwed to a rotating plate, above the specimen’s table. The objective lenses are also
interchangeable, by rotating the plate. There are several objective lenses (3-4), depending
on the type of the microscope. The magnifications of objective lenses are 4x, 10X, 20X,
40X, 45X or 100X.
First, you have to look for the light by using a mirror, or push at the button to put on the
microscope’s lamp. Then determine the amount of light using the diaphragm or by
turning the lamp button. Then use small magnification (10X4, or 5X10) to examine the
whole specimen. After you got an interesting area, use larger magnification, e.g. 10X20
or 10X40, etc. After you have found what you are looking for, draw them on your
sketch book!!!
In this lab activity you have to learn about the 4 basic tissues. They are found everywhere
in our body, also is all organs, that is why they are called the basic tissues. The 4 basic
tissues are the epithelium, connective tissues, muscles and nerves. All kinds of tissues
consist of cells and intercellular substance. The differences between the various basic
tissues are in the type of cells and the amount and type of intercellular substance.
Epithelium
Epithelium lines the surfaces of the body and some are in the form of glands. The
surfaces lined by epithelium can be the outer surface of the body, outer surface of and
organ, or inner surface of a hollow organ such as the intestines, urinary bladder, blood
vessel, etc. when you are looking at an epithelium lining a surface, arrange the specimen
so that the epithelial surface is located above.
The main characteristics of an epithelium are: they consist mainly of cells, and very
scarce intercellular substance. Epitheliums lining the surface got their names according
to the amount/shape of cell layers, shape of the cells at the surface, structures found on
the surface, specialized cells that are found in between their cells, or according to their
place, e.g. keratinized stratified squamous epithelium, simple columnar epithelium,
respiratory epithelium (pseudo-stratified epithelium with cilia and goblet cells), etc. In
addition, there are also epitheliums having special names, due to lack of the
characteristics mentioned above, e.g. transitional epithelium.
Glands are epitheliums that invaginate into the underlying connective tissues. In an
exocrine gland, the relation with the surface remains in the form of excretory ducts, while
in endocrine glands relation with the surface disappear. Therefore, an endocrine gland has
no excretory duct.
Connective tissue
Connective tissue contains more intercellular substance compared to epithelium.
Intercellular substance consists of fibers and amorphous ground substance containing
tissue fluid. There are 3 kinds of fibers, collagen, elastic and reticular fibers. There are
many kinds of connective tissue. To make it simple, connective tissues can be grouped
according to their density and function, into 3 main groups:
 Loose (areolar) connective tissue. In areolar connective tissue, the proportion
between cell and intercellular substance more or less the same. According to cell
type, proportion of cell type, type of fiber, proportion of each type of fiber and
amorphous ground substance, areolar connective tissue consists of: mesenchymal
connective tissue (mesenchyme), gelatinous connective tissue (mucous tissue),
loose connective tissue, adipose tissue, and reticular tissue.
 Dense connective tissue. In these kinds of tissues, the fibers are dominant, while
cells and amorphous ground substance are few. According to the type of fiber that
is dominant, there are dense collagen and elastic connective tissue.
 Specialized connective tissue. Specialized connective tissue can have
hard/resilient intercellular substance (matrix), i.e. bone and cartilage, or fluid
matrix, i.e. the blood.
Muscles
Muscle tissue mainly consists of muscle cells that look like a fiber and therefore called
muscle fibers. There are 3 kinds of muscle fibers i.e.: smooth, skeletal, and cardiac
muscle fiber.
Smooth muscle fibers are fusiform (spindle shaped) and have a centrally placed nucleus.
Smooth muscle fibers are difficult to differentiate from connective tissue fibers
(collagen). To differentiate you have to use high magnification, and look at the nucleus.
If you can find a nucleus at the middle of a fiber, then the fiber is a smooth muscle fiber.
Skeletal muscle fibers are big and long. In longitudinal section they show cross striations.
The nuclei are in a row at the periphery. In transverse section, the cytoplasm is fibrillar,
and the fibrils are grouped to form the Connheim’s field.
Cardiac muscle fibers branch and interconnected to each other. The nucleus is centrally
located and surrounded by perinuclear space. Cardiac muscle fibers contact each other at
their ends and the site of contact is called the intercalated disk that appears as a line
perpendicular to the fiber. Transverse section at the perinuclear space shows a fiber with
a hole at the center.
Nerves
Nerve tissue will be elaborated more in the module of Neuroscience, therefore, in this
module you only have to look for the motor neuron that is located in the anterior horn of
the spinal cord and the peripheral nerve.
A neuron is a big cell and consists of a cell body and cytoplasmic projections that are the
dendrites and axon. The cell body contains the nucleus. The characteristics of a neuron
are the big vesicular nucleus, and the prominent nucleolus. The cytoplasm contains Nissl
bodies, and these Nissl bodies are found in the cytoplasm of the body and dendrites, but
lacking in the axon. The proximal of an axon appears clear and called axon hillock.
In the peripheral nerve you can find the axons surrounded by myelin. Surrounding the
myelin there are loose connective tissue called the endoneurium. In longitudinal section,
you can find the node of Ranvier.
Jaringan
Yang perlu dipelajari
• Epitel dan
kelenjar
• Sel pada epitel selapis (gepeng*, kuboid, dan torak/silindris*)
• Jaringan
penyambung
• Sel jaringan penyambung embrional (mesenkim, mukosa)
• Sel jaringan penyambung jarang*
• Sel jaringan penyambung padat (kolagen*, elastin)
• Sel jaringan lemak (univakuolar*, multivakuolar)
• Sel jaringan retikular
• Sel jaringan tulang rawan (hialin*, elastin, fibrokartilago)
• Sel jaringan tulang (pertulangan kondral*, desmal, tulang gosok*)
• Otot
• Sel otot polos*
• Sel otot rangka*
• Sel otot jantung*
• Saraf
• Sel saraf /neuron (badan sel saraf*, serat saraf*)
• Sel penyokong (sel glia, sel Schwann*)
• Sel pada epitel bertingkat*
• Sel pada epitel berlapis gepeng (dengan lapisan tanduk*, tanpa lapisan
tanduk)
• Sel pada epitel berlapis kuboid
• Sel pada epitel berlapis torak
• Sel pada epitel transisional*
• Sel kelenjar (saluran keluar*, pars terminalis*)
* yang diutamakan – dicari lebih dahulu
Sediaan
Jantung
Yang dicari
Epitel selapis gepeng (endotel) – melapisi bagian dalam
Serat otot jantung, diskus interkalaris
Sel lemak univakuolar (di lapisan subperikardium)
Duodenum/yeyunum/ileum Epitel selapis silindris, dengan mikrovilli dan sel goblet
Serat otot polos
Badan sel saraf di antara 2 lapisan otot
Jaringan ikat jarang di lapisan terluar (adventisia/serosa)
Trakea
Epitel bertingkat, tulang rawan hialin, perikondrium
Kondroblas, kondrosit, sel isogen, teritorium-interteritorium
Kulit jari/ketiak
Epitel berlapis gepeng dengan lapisan tanduk
Epitel berlapis kuboid ( saluran keluar kelenjar)
Pars terminalis kelenjar keringat (merokrin pada kulit jari, apokrin
pada kulit ketiak)
Kelenjar sebasea (pada kulit ketiak)
Folikel rambut (pada kulit ketiak)
Vesika urinaria/ureter
Epitel transisional – dengan sel payung
Serat otot polos
Jaringan ikat
jarang/longgar
Fibroblast
Fibrosit
Histiosit (makrofag jaringan)
Sel mast
Serat kolagen
Serat elastin
Kapilar (endotel, perisit )
Jaringan ikat padat kolagen Serat kolagen, fibrosit
Penulangan kondral
Zona rihat
Zona proliferasi
Zona maturasi
Zona kalsifikasi
Zona degenerasi
Zona osifikasi - Balok tulang
Osteosit
Osteoblas
Osteoklas, lakuna Howship
Sumsum tulang
Tulang pipa – sajian gosok
System Havers
Kanal Havers
Lamel havers
Lidah
Serat otot rangka - garis-garis seran lintang
Jaringan saraf perifir
Serat saraf (akson), selubung myelin, sel Schwann
Kanal Volkman
Lamel interstisial
Lakuna, kanalikuli