OHE Flashcards
is branch of medical science that deals
with the study of minute structures of the tissues
and organs of the body.
Histology
is a branch of science that deals
with the study of microscopic structures of oral and
dental tissues.
oral histology
s a group of cells with intercellular substance
and tissue fluid, performing a definite function
Tissue
Group
of tissue performing special functions form the
organs
Aggregation of organs with definite
functions is known as
organ system
is a unit of living matter
Cell
cell is made
cytoplasm and nucleus
The external boundary of a cell is known as
plasma membrane or plasmalemma
Protoplasm inside the cell is the cytoplasm
containing 3
Organelles
Inclusion bodies
Amorphous matrix.
The most prominent organelle of the cell.
Nucleus
The nucleus is covered by a thin membrane known as
Nuclear membrane
Within the nucleus are the nucleolus and irregular masses known
chromatin material
chromatin material composed of
RNA
Suspended in ground substance known as
Karyolymph (nucleoplasm)
are membrane-bound cell organelles
Mitochondria
Chemical energy
produced by the mitochondria is stored in a small molecule called
Adenosine triphosphate (ATP)
shows various forms but the most common is in form of plates or lamellae or plates may dilate to bowl-shaped
structure (cisternae).
Golgi complex
Consist of minute fluid containing
membrane-bound tubules known as canaliculi, cisternae, or vesicles which may form sometimes a network (reticulum) or maybe in
form of granules (when free are known as ribosomes or polysomes)
Endoplasmic reticulum
When granules adhere to the outside membrane, they form
Rough surface endoplasmic reticulum (R E R)
tubules lacking
ribosomes are known as
smooth surfaced endoplasmic reticulum (S
E R).
are located close to nucleus in a
specialized area of the cytoplasm known as centrosome or cell
center.
Centrioles or Liposomes
these appear as two stained bodies
(in light microscope) or
hallow and tubular (in electron microscope).
are minute threadlike bodies of different lengths and
circumferences
Filaments
In ______the threadlike structures are
called tonofilaments of fibroblast, cytoplasmic fibril; nerve cells, neurofilaments, and of muscles, myofilaments
Mitosis
are single membrane-bound bodies containing
powerful digesting enzymes which assist the cell in destroying foreign particles or prevent the cell from overproducing by digesting some of the secretions.
Lysosomes
Are tiny, straight and tubular organelles often of different lengths.
Microtubules
The inclusion bodies are composed of 7
carbohydrates
protein,
pigments
crystalloids
fat
gas
and other metabolites or foreign
materials.
are packed materials to be secreted. These
are of various diameter and density but the most common form is spheroid
Secretion granules
such as lipofuscin observed in muscles and nerve fibers; melanin in melanocytes; and hemoglobin in red blood corpuscles.
Pigments
has variable size and closely associated with
mitochondria and built to function as an energy source
Lipids (fat)
a storage form of glucose, is found
predominantly in liver and muscle cells as cytoplasmic granules. In
liver cells, these granules group together to form rosettes,
frequently in close proximity to smooth endoplasmic reticulum
Glycogen granules
in electron microscope have been observed
to be associated with nucleus, endoplasmic reticulum,
mitochondria, golgi apparatus, lysosomes and with secretion
granule.
Crystalline particles
Electron microscope have been observed to be associated with 6.
NUCLEUS
ENDOPLASMIC RETICULUM
MITOCHONDRIA
GOLGI APPARATUS
LYSOSOME
SECRETION GRANULE
The organelles and inclusion bodies are suspended in a formless material known a
amorphous matrix
holds the cells together and serves as a medium for the passing of nutrients and waste materials from capillaries.
Intercellular substance (fibrous or amorphous in nature)
had been grouped based on the similarities of its
components, difference in form and number of cells, in types and amounts of intercellular substance and tissue fluid.
human tissue
What is the four fundamental tissue?
Epithelial tissues (ectoderm)
Connective tissue (mesoderm)
Nervous tissue (ectoderm)
Muscular tissue (mesoderm)
serves as surface covering of the skin and
mucous membrane and give rise to organs like glandular organs
Epithelial tissue
What are the 5 glandular organs
pancreas
Liver
thyroid gland
salivary gland
dental organ.
What are the 3 types of epithelial?
Simple epithelium
Pseudostratified columnar
Stratified epithelium
cells are arranged in single layer.
Simple epithelium
Scale-like of flat cell
Squamous
Cube-shaped
Cuboidal
Tall and narrow
columnar
actually composed of single layer of
columnar cells arranged in such a way that the epitheliumappears to have several layers of cells, cause by difference in location of nuclei
Pseudostratified columnar
consists of two or three more layers of
cells
Stratified epithelium
What are the 6 Connective tissue (mesoderm)
Fibrous tissue in lamina propria
Loose, areolar tissue
Adipose tissue
Hemopoietic tissue
Cartilage
Bone
has a large amount of
intercellular substance and few cells (tendons and ligaments).
Fibrous tissue in lamina propria
The intercellular
substance are of 2 kind
Fibrillar – (with numerous fibroblasts)
Amorphous (shapeless, no differentiation)
What is the 2 types of fibrillar
Collagen and elastic fibers
with numerous fibroblast
Fibrilla
shapeless, no differentiation
amorphous
has small amount of cells, loose and thin
network of fibrous intercellular substance held together by a large amount of amorphous substance.
Areolar tissue
is made up of areolar tissue and fat tissue.
fascia
compose of fat cells held together by fibrous
intercellular substance. Fat cells maybe filled with fat so thatcytoplasm is pressed into a thin layer around the periphery of the cells and nucleus is pushed to the side of the cell.
Fat tissue
produces blood cells as well as removing the
worn out blood cell from the blood stream.
Hemopoietic Tissue
alcified connective tissue containing large amount of
dense fibrous intercellular substance (with amorphous substance)
Bone
Cells with in the bone are the
osteocytes
osteocytes found spaces known as
lacunae
Tissue of central and peripheral nervous system
Nervous tissue (ectoderm)
is composed of nerve cells called neuron capable of
reacting to stimuli (irritability) and of transmission of wave excitation or nerve impulse.
Nervous tissue
the nervous system consists of 2 chief divisions
-Central nervous system (brain and spinal cord)
-peripheral nervous system (nerve of various organs of the body)
Cells of the central nervous system are supported by
neuroglia (nerve glue)
This tissue is composed of muscle cells which
are long and has been called as muscle fibers.
Muscular tissue
what are the 2 types of Muscular tissue (mesoderm)
Smooth involuntary
Striated involuntary
where the cytoplasm has cross striations
Striated muscle
where the cytoplasm of the muscle
appear clear (walls of intestine, walls of blood vessel, and roots of hair)
Smooth muscle tissue
contraction of muscle fibers maybe controlled by the
individual (arms, legs, other parts of the body, tongue, cheeks, lips and soft palate).
Voluntary muscles (skeletal muscle)
contraction of its fibers is not under the control of
the individual’s will.
Involuntary muscle (cardiac muscle)
