BY 30 – Fall 2001
10.1. Definition
of Tissues
a. A _____________________ is a group of cells that function together for a common purpose, and their study is called _________________________.
b. The four basic tissue types of the human body are _____________________, ______________________________, ______________________________, and ____________________________.
c. The tissue type that covers the outer body surface as well as internal body surfaces is called _________________________. This tissue type also forms ______________________ whose role is to synthesize and secrete substances.
d. The tissue type that typically has large amounts of extracellular matrix is called ________________________. Specifically, the matrix consists of ____________________ embedded in ______________________________.
e. The tissue type that has the ability to contract is called _______________, of which there are three types: ____________________ connects to bones via ________________________; _______________________ is found in the heart; and __________________ is found in the walls of blood vessels and most organs.
f. __________________________ tissue is found in the brain and spinal cord, which together constitute the ________________________ nervous system. By contrast, nervous tissue found in areas outside the brain and spinal cord constitutes the ________________________ nervous system.
g. Nervous tissue consists of two basic cell types called ___________________ and ________________________. Of the two, _____________________ are capable of generating and conducting electrical signals, while the _______________________ provide metabolic and mechanical support.
10.2.
Intercellular Junctions
a. Intercellular junctions involve contact between two ____________________ cells involving interactions between their ____________________________.
b. In some tissue types, intercellular junctions provide boundaries subdividing cell membranes into ____________________ and _____________________ portions, each of which typically have different membrane proteins.
c. The type of intercellular junction that limits permeability between two adjacent cells is called the ________________________, formed as a result of interaction between membrane proteins. In general, the more extensive the contact, the __________________ the permeability between adjacent cells.
d. The two types of intercellular junctions that provide for mechanical adherence between adjacent cell types are called ____________________________ and ____________________________. Both contain a dense layer of protein just beneath the cell membrane called __________________________. Both also contain ______________________ that interact with one another in the extracellular space, providing the attachment. While adherans junctions have ___________________________ that attach to the plaque within the cell, desmosomes have ________________________________.
e. The type of intercellular junction that anchors a cell to its basement membrane is called a _______________________________, which resembles the _______________________________, except only one cell is involved.
f. The type of intercellular junction which allows for direct communication between adjacent cells is called the _________________________________, formed from circular channels called ____________________________. The middle of this structure contains a ______________________ through which ions and small regulatory molecules can pass.
10.3. Epithelia
a. Epithelia share a number of characteristic features including: a high _______________________; possessing little _________________________; possessing a ________________________; being ______________________; and having a high rate of _______________________.
b. The basement membrane consists of two layers called the ___________________________ and _______________________. Of these two, cells form hemidesmosomes with the ___________________________.
c. Because of the lack of blood vessels, nutrients supplying epithelia come from blood vessels located in the underlying ______________________________.
d. Epithelial cells often feature surface specializations such as _____________________ or _____________________. Of the two, it is the ____________________ which have microfilaments in their interior, while it is the cilia which have ____________________________.
e. Microtubules found within cilia and flagella feature the 9+2 arrangement meaning that there are __________________ doublets at the periphery and _____________________ single microtubules found in the middle. It is the protein _________________, which forms the arms that attach to the neighboring microtubules, allowing movement. At the base of cilia and flagella are found __________________________, structures derived from ___________________________.
f. _____________________ are responsible for the movement of entire cells (for example the movement of _____________________________). ______________________ are responsible for moving particular substances along the cell surface (for example the ________________________ escalator.
g. Epithelia are classified on the basis of the number of cell _________________ and the _________________________ of the cells. Of these, simple epithelia consist of __________________ layer while stratified epithelia consist of ___________________ layers. Cells that are flat in appearance are called ____________________; cells which have equal dimensions are called _____________________, and cells that are rectangular are called _______________________________.
h. The tissue type which consists of a single layer of flattened cells is called ___________________________, which when found lining the heart, blood and lymphatic vessels is called _________________________; and when lining body cavities like the peritoneal, pericardial, and pleural cavities, it is called _______________________________.
i. The tissue type which consists of a single layer of cells with equal dimensions is called ______________________ while the tissue type which consists of a single layer of rectangular cells is called the ___________________________. In the latter case, when the cell is secretory, its nucleus is located in the ______________________ part of the cell.
j. A cell within a simple columnar epithelium that secretes mucus is called the ______________________. Mucus consists of the glycoprotein ____________________ which is put into solution with water. Mucus serves two purpose: ___________________________ and it helps to trap ______________________ material within airways.
k. The type of epithelium in which each cell contacts the basement membrane, but the nuclei appear at different levels is called _______________________. This tissue type has three principle cell types called ___________________; _______________________; and __________________________. Of these three, it is the ___________________ cell that undergoes mitotic division.
l. A stratified squamous epithelium has _____________________ cells located adjacent to the basement membrane and ____________________ cells located at the surface. This tissue type is further subdivided into _________________ and ____________________ depending on whether the surface cells retain their organelles (_______________________ if they do; ____________________ if they don’t). ________________________ is found on the outer surface of the body; ___________________________ is found lining certain internal surfaces.
m. A stratified epithelium in which the surface cells appear as cubes is called _____________________ whereas _______________________ has surface cells that are rectangular. Both tissue types are rare and serve protective functions as well as providing a __________________- tight barrier.
n. The epithelial type which changes its appearance depending on the degree of stretch of the organ is called __________________________. In this tissue, the surface cells are called ___________________________, which maintain a ________________________-tight barrier. This tissue type is found in the ___________________________ and ____________________________.
10.4. Glands
a. All glands are derived from _________________________ and have the function of ______________________ substances. When these substances are released to the blood stream, this gland is called an _______________________ gland, and the substances they release are called __________________________. When these substances are released onto body surfaces via __________________________, this gland is called an _______________________________ gland.
b. An exocrine gland typically has a secretory portion called the ____________ and a duct system. It is also frequently subdivided into _________________ and _____________________ by connective tissue.
c. An exocrine gland with only 1 cell is called a ________________________ gland; the _________________________ cell is one example. By contrast, multicellular glands can be further distinguished on the basis of their _________________________ and ____________________________.
d. Exocrine glands can be classified functionally as being _____________________________; _________________________; or _______________________________. Of these, ___________________ secretion probably doesn’t occur in humans, and _____________________ secretion is the most common, in which the secretions are released from the cell by _______________________________.
e. An example of _____________________ secretion is the sebaceous gland, where the entire cell sloughs off into the lumen carrying along its secretions.