Question | Answer |
Why study Histology? | It intertwines the disciplines of cell biology, biochemistry, physiology and pathology. |
Histology class objectives are? | 1 teach normal tissue structure and function. 2 compare normal vs pathological micro-anatomical structure and function. 3 learn basic concepts of histology ie...4 tissue types. |
List the hierarchy of living things | 1. atoms 2. molecules 3. cells 4. tissues 5. organs 6. organ systems 7. organisms |
what is tissue? | 2 OR more cells grouped together for a common function. |
name the four basic tissue types. | 1. epithelium 2. connective tissue 3. muscle tissue 4. Nervous tissue |
How many steps involved in preparing tissue for study? | six |
what are the steps involved in preparing tissue? | fixation, dehydration, clearing, embedding, sectioning, mounting/staining |
what are the most commonly used stains in histology | Hematoxylin and Eosin |
Name the three embryonic Germ layers | Endoderm, Mesoderm, Ectoderm |
How many Embryonic Germ layers are there? | three |
give the four part outline of Epithelium as described in class | germ layers, two forms of epithelium, its function, its classifications |
What is the most abundant of the four types of tissues | Connective tissue |
list some of the sections that may appear on a slide. | cross section, longitudinal, oblique, |
Describe the each of the steps in preparing a histo slide. | Fixation: treating with a chemical agent to retard alterations. 2.Dehydration with alcohol. 3.clearing with xylene makes the tissue clear. 4 embedding the tissue in paraffin. 5 cutting in Sections. 6 mounting on a slide and then staining. |
What is the most common type of microscope used in histology? | compound microscope is the most common. because it uses a group of lenses. |
Name another type of imaging techniques for slides. | Digital imagining for immediate visualization, modification, and enhancement. |
Classifications of tissue based on what? | the tissue layers, and the shape of the cells. |
name the two types of layers of tissue. | simple and stratified |
what are the shapes of tissue cells? | squamous, cuboidal, columnar |
name the three types of simple single layered tissue. | simple squamous, simple cuboidal, simple columnar. |
how is the shape of the nucleus differentiated between cuboidal and columnar and squamous? | Cuboidal cells have round nuclei and squamous and columnar have oval nuclei. |
simple cell layering has how many layers | one layer |
statified tissue has how many layers of cells? | more than two layers of cells. |
Name three types of tissue | stratified squamous, stratified cuboidal, psuedostratified columnar, transitional tissues |
transitonal tissue has what kinds of tissue? | It has many types as the tissue changes tasks as it gets deeper. |
describe pseudostratified ciliated columnar epithelium. | cilia at the top above columnar cytoplasm of pseudostratified columnarasasl cells. |
name the two apical domain surface modifications and there use. | microvilli common in intestines, kidneys, and cilia common in trachea, bronchi and oviduct and ear canal. |
name the six functions of epithelial tissue | protection, transcellular transportation, secretions, selective permeability, absorption, detection of sensations. |
What is a lumen? | the space between cells. |
are epithelial cells vascular or avascular? | avascular |
Where role does the basal lamina play with epithelial cells? | separates the tissue from, and allows nourishment and oxygen through from underlying connective tissue. |
The three types of basal surface specializations are | basal lamina, plasma membrane enfolding, hemidesmosomes. |
the lateral domain(membrane) specializations reveal the presence of | junctional complexes. |
There are three types of junctional complexes in the lateral domain | 1 occluding junctions 2 anchoring junctions 3communicating junctions. |
characteristics of occluding junctions are | tight impermeable barriers |
characteristics of Anchoring junctions are | desosomes or adherence to other cells or lamina |
characteristics of communicating junctions are | gap junctions where communication between cells takes place. |
Basal Lamina for | the boundary between epithelium and underlying connective tissue. |
Plasma membrane enfolding | increases surface area of the cell. |
hemidesmosomes | attach basal cell membrane to basal lamina |
Desmosomes are | weld-like junctins along the lateral cell membranes that help to resist shearing forces. |
the two major groups of Glands are | Exocrine and Endocrine glands. |
Cytokines are | signaling molecules that communicate between cells |
cytokines are released by | a signaling cell |
Name the three effects cytokines can have on target cells | autocrine, paracrine, and endocrine |
autocrine cytokrines do what when released | stimulate the cell that released them. |
Paracrine cytokines the target cells is | located in the vicinity so don't have to enter the vascular system for distribution. |
endcrine cytokine signaling has to travel far and thus | is transported by blood or the lymph system. |
Exocrine glands secrete their products via | ducts on the external or internal epithelial surface from which they originate. |
unicellular exocrine glands are the | simplest forms of exocrine glands |
a primary example of a unicellular exocrine gland is the | goblet cell |
the number of Exocrine glands are | unicellular and multicellular. |
Multicellular exocrne glands exist as | organized clusters of secretory units. |
Exocrine glands are catagorized by three things | the nature of secretion, the mode of secretion and the numbe of cells. |
The three modes of secretion of exocrines | holocrine, merocrine, apocrine |
halocrine secretes as they mature they | become the secretory product. |
exocrine glands secrete their products via | a duct to the surface of their epithelial 0rigin. |
merocrine glands secretions occur via | exocytosis, as a result neither cell membrane nor cytoplasm becomes part of the secretion. |
apocrine glands are thought to secrete... | a small portion of the apical cytoplasm with the secretory product. |
Endocrine glands are ductless thus | release directly into the bloodstream or the lymphatic system. |
Regarding ducts the endocrine gland is which? and the exocrine is which? | endocrine is ductless, exocrine has ducts. |
the major endocrine glands are | superarenal(adrenal), pituitary, thyroid, parathyroid, ovaries, testes, placenta |
Secretory cells are arranged in two ways | as cords of cells or in a follicular arrangement. Cord type being the most common. |
the arrangement of the cord type form | anastomosing cords around capillaries or blood sinusoids. ie: pituitary gland |
Whereas Follicular cells arrange to | surround a cavity that receives and stores the seceted hormone. ie thyroid gland |