Chapter 4 Lecture
Choose the answer that shows the correct order for the standard preparation of a histological specimen. (1) sectioning, (2) staining, (3) fixation (1) fixation, (2) sectioning, (3) staining (1) fixation, (2) staining, (3) sectioning (1) staining, (2) fixation, (3) sectioning (1) sectioning, (2) fixation, (3) staining
(1) fixation, (2) sectioning, (3) staining
What do the glands shown in A and B both have in common? Both are exocrine glands. Both are unicellular. Both are sebaceous glands. Both are endocrine glands. See problem 20 Homework chapter 4
Both are exocrine glands. Both glands secrete substances onto body surfaces or into body cavities.
Which is the most atypical connective tissue since it neither connects structures nor provides structural support? areolar connective tissue cartilage osseous blood
Blood Blood, the fluid connective tissue (CT) within blood vessels, is the most atypical CT. It does not act as a binding or packing material; it does not provide structural support. It is classified as a CT only because it develops from mesenchyme and consists of cells (blood cells) surrounded by an extracellular fluid matrix (blood plasma).
Which event must precede all others during tissue repair? 1. Fibroblasts multiply and produce collagen fibers in the damaged area. 2. Epithelial cells multiply and migrate over the damaged area. 3. Granulation tissue forms in the damaged area. 4. Inflammation occurs in the damaged area.
Inflammation occurs in the damaged area. Inflammation sets the stage for the tissue repair process by bringing defense cells and clotting proteins into the damaged area to prevent the spread of infection.
Which of the following characteristics is lacking in the typical areolar connective tissue pictured in the figure? vascularity ability to support other tissues elastic properties ground substance None of these characteristics is lacking.
None of these characteristics is lacking This tissue has all of these abilities.
Marfan's syndrome is a disease associated with faulty manufacture of the extracellular protein fibrillin. Since this is a component of elastin, in which of the numbered cells would the damaged gene be expressed? 2 3 4 5 See problem 36 Homework chapter 4
2 Cell 2 is a fibroblast, which is the primary producer of the major fibers (including elastin and fibrillin) in connective tissue proper. It can be identified by its numerous cell extensions.
Which numbered cell type initiates inflammatory responses to infection or tissue damage? 3 4 5 6
5 Cell 5 is a mast cell, which produces and secretes inflammation-triggering chemicals, such as histamine. Note the secretory granules within the pictured cell.
Which of the following connective tissues is richly vascularized and consists of more cells than extracellular matrix? Hyaline cartilage Adipose Areolar Dense regular
Adipose Adipose is similar to areolar connective tissue in structure and function, but contains many more fat-storing cells called adipocytes. These cells account for 90% of this tissue's mass. The matrix is scanty and the cells are packed closely together, giving adipose tissue a chicken-wire appearance. It is richly vascularized, indicating its high metabolic activity.
Which of the following statements is true? 1. Closely packed bundles of collagen fibers are characteristic of loose connective tissues. 2. Dense irregular connective tissue has a high proportion of elastic fibers. 3. Dense connective tissue is dominated by collagen fibers. 4. Loose connective tissue includes cartilage.
Dense irregular connective tissue is dominated by collagen fibers Dense regular connective tissue contains closely packed bundles of collagen fibers running in the same direction, parallel to the direction of pull. This arrangement results in white, flexible structures with great resistance to tension (pulling forces) where the tension is exerted in a single direction.
How do endocrine and exocrine glands differ? 1. Exocrine glands can be multicellular. 2. Endocrine glands do not use ducts. 3. Exocrine glands use exocytosis to release their products. 4. Exocrine glands secrete hormones.
Endocrine glands do not use ducts Endocrine glands secrete substances (hormones) into blood without the use of ducts, whereas exocrine glands use ducts to secrete substances into the external environment.
Which of the following accurately describe the basement membrane which underlies epithelial tissues? 1. The basement membrane consists of connective tissue and covers the apical surface of the epithelium. 2. The basement membrane consists of large collagen fibers which create an impermeable barrier. 3. Epithelial cancers may have the ability to penetrate through the basement membrane and spread to underlying tissues. 4. All of the above.
Epithelial cancers may have the ability to penetrate through the basement membrane and spread to underlying tissues. A characteristic of epithelial cancers is their ability to breach the basement membrane barrier and invade deeper tissues.
Which tissue type consists of a sheet of cells that covers a body surface or lines a body cavity? nervous tissue connective tissue muscle tissue epithelial tissue
Epithelial tissue
Which of the following is a property of epithelial tissue? Epithelial tissue does not exhibit polarity. Epithelial tissue is innervated. Epithelial tissue contains blood vessels. Epithelial tissue is typically unable to regenerate.
Epithelial tissue is innervated.
What tissue type has polarity and is avascular? muscle nervous tissue epithelium connective tissue
Epithelium Epithelia have polarity, which is to say that there is directionality. There is always an exposed surface and an attached surface. Epithelia are also avascular.
Pseudostratified epithelia are well adapted to the digestive system because the cilia increase the surface area for absorption. True False
False Pseudostratified epithelia are found in the linings of the respiratory tract. Cilia are used to move substances across membrane surfaces. Microvilli are used to increase surface area.
All muscle cells contain striations. True False
False Smooth muscle cells do not contain striations. Although they do contain myofilaments, their arrangement is not regular enough to generate the striations seen in skeletal or cardiac muscle cells.
Which of the following would be a characteristic that would increase absorption in a mucosal membrane? Keratinization Microvilli Stratification Calcification
Microvilli
__________ are water-soluble, complex glycoproteins that are secreted by goblet cells. Mucin Proteoglycan Albumin Keratin Collagen
Mucin Like mucous cells, goblet cells are unicellular exocrine glands that secrete mucin, a protein that combines with water to form mucus. In goblet cells, the cuplike accumulation of mucin distends the top of the cell, making these cells look like a glass with a stem, thus "goblet" cell. This distortion does not occur in mucous cells.
An exocrine gland that has an unbranched duct would be classified as a __________. unicellular compound gland multicellular simple gland multicellular compound gland unicellular simple gland
Multicellular simple gland Multicellular exocrine glands with unbranched ducts are "simple"; those with branched ducts are "compound." Unicellular exocrine glands do not have ducts.
You observe a tissue under a microscope. There appears to be a lumen on one side of the tissue. Lining this lumen is a single layer of epithelial cells that seem to have long, fingerlike projections. Beneath the projections, the cells seem to have the shape of shoeboxes and are packed tightly together. What type of tissue are you looking at? transitional epithelium stratified squamous epithelium simple columnar epithelium simple cuboidal epithelium
Simple columnar epithelium The shoebox represents the columnar shape. It is a simple epithelium because the cells are arranged into a single layer. Additionally, the fingerlike projections are likely to be microvilli.
Injured cartilage might heal more quickly if a treatment were discovered that would __________. 1. prevent chondrocytes from dividing and thereby reducing the relative amount of matrix that is present in the cartilage 2. stimulate blood vessels to develop within cartilage 3. stimulate calcification of cartilage 4. All of the listed responses are correct.
Stimulate blood vessels to develop within cartilage Cartilage is normally avascular, so nutrients required for healing must diffuse from distant blood vessels, which delays the healing process.
Which of the following statements is INCORRECT? 1. Mucous membranes line exits and entrances to the body. 2. The cutaneous membrane is made of a simple columnar epithelium 3. The cutaneous membrane is a dry membrane exposed to air. 4. Serous membranes line body cavities and organs.
The cutaneous membrane is made of a simple columnar epithelium The cutaneous membrane, a "dry" membrane exposed to air, consists of a keratinized, stratified squamous epithelium called the epidermis, and an underlying layer of connective tissue called the dermis.
Which of the following is NOT a characteristic of stratified squamous epithelia (SSE)? 1. SSE protect underlying tissues in areas subjected to wear and tear. 2. The epidermis is a dry epithelium consisting of non-keratinized SSE. 3. The basal cells of SSE are cuboidal or columnar. 4. SSE form a barrier between the internal and external environments.
The epidermis is a dry epithelium consisting of non-keratinized SSE. The epidermis (of the skin) is a dry epithelium consisting of keratinized SSE. Non-keratinized SSE form the moist linings of the esophagus, mouth, and vagina.
Which of the following describes a holocrine gland? 1. The secretory cells release their products by exocytosis. 2. Holocrine glands secrete their products through a hollow, tubular duct. 3. The secretory cells release their products by rupturing. 4. The apex of the secretory cells pinches off to release their products.
The secretory cells release their products by rupturing. Secretory cells of holocrine glands accumulate their products within them until they rupture. They are replaced by the division of underlying cells. Sebaceous (oil) glands of the skin are the only true example of holocrine glands in the human body.
Why are adipose tissue, blood, and bone all considered to be connective tissues? 1. They have the same types of cells. 2. They all have collagen and elastic fibers in their extracellular matrix. 3. They connect to each other. 4. They have a common origin: the embryonic tissue mesenchyme.
They have a common origin: the embryonic tissue mesenchyme. Adipose tissue, bone, and blood (like all connective tissues) are derived from mesenchyme, an embryonic tissue. Also common to all connective tissues is the presence of cells surrounded by extracellular matrix that consists of fibers and ground substance.
Which types of cell junctions are needed in a mucosal membrane, such as the digestive tract, to keep the digestive enzymes, juices, and bacteria from leaking out? Gap junctions Tight junctions Desmosomes
Tight junctions
All epithelia have two surfaces, an apical surface and a basal surface, that differ in both structure and function. This property is called polarity. True False
True All epithelia exhibit polarity, which is defined by the presence of an apical, or free, surface and a basal, or attached, surface that differ in both structure and function.
Your friend is trying to convince you that if the ligaments binding the bones together at your freely movable joints (such as your knee, shoulder, and hip joints) contained a higher percentage of elastic fibers, you would be much more flexible. Is this true? If so, would this present any serious problems? 1. No, this is not true. Joint flexibility is determined only by the flexibility of the skeletal muscles that cross the joint, not the composition of its reinforcing ligaments. 2. Yes, ligaments that are more elastic (or stretchy) will provide greater flexibility, but at the expense of joint stability. The joints would be prone to misalignment and dislocation. 3. Yes, ligaments that are more elastic (or stretchy) will provide greater flexibility. This should not cause any problems since elastic and collagen fibers are equal in tensile strength. 4. No, this is not true. The parallel arrangement of collagen fibers in dense regular connective tissue allows ligaments to stretch much more than elastic fibers could.
Yes, ligaments that are more elastic (or stretchy) will provide greater flexibility, but at the expense of joint stability. The joints would be prone to misalignment and dislocation. In general, anything that increases the flexibility, or mobility (range of motion), of a joint will reduce joint stability. This will increase the likelihood of joint dislocations and misalignment.
Which of the following does NOT describe a multicellular exocrine gland? simple glands a gland that secretes sweat a tubular gland a gland that secretes hormones
a gland that secretes hormones The ductless glands that secrete hormones are called endocrine glands. Exocrine glands are all ducted glands.
Which of the following is NOT a role of connective tissue? absorption transport insulation support
absorption Absorption, the movement of substances into the body, is a role of epithelial tissue. Roles of connective tissue include binding and support, protection, insulation, and transportation of substances, via blood, within the body.
In connective tissue, the role of elastic fibers is to __________. provide high tensile strength form delicate networks around blood vessels retain fluid allow the tissue to stretch and recoil
allow the tissue to stretch and recoil Elastic fibers contain elastin, a rubberlike protein that allows them to stretch and recoil like rubber bands.
Which tissue is correctly paired with its primary immature cell type? bone; osteoblast cartilage; fibroblast bone; fibrocyte connective tissue proper; chondrocyte
bone; osteoblast The osteoblast becomes an osteocyte, the primary mature cell type for bone.
Which tissues have little to no functional regenerative capacity? cardiac and smooth muscle nervous tissue and bone cardiac muscle and nervous tissue epithelial tissue and areolar connective tissue
cardiac and nervous tissue Cardiac muscle and the nervous tissue in the brain and spinal cord have virtually no functional regenerative capacity, and they are routinely replaced by scar tissue.
What process is depicted in the basal layer of the glandular epithelium shown in B? exocytosis cell fragmentation endocytosis cell division See problem 23 Homework chapter 4
cell division Cells are regenerated by division in the basal layer and migrate toward the apical surface to replace cells lost by fragmentation. Cell division is indicated by the mitotic phase cells located in the deepest (basal) layer of the glandular epithelium.
You observe a uniform tissue under a microscope. There is no lumen. The material looks densely packed, but you do not observe many nuclei. It appears that there are strands of fibers running in parallel directions. What type of tissue are you looking at? muscle tissue nervous tissue connective tissue epithelial tissue
connective tissue You are probably looking at dense regular connective tissue, which primarily consists of parallel collagen fibers. All other primary tissues are composed mainly of cells, but connective tissues consist largely of nonliving extracellular matrix, which separates, often widely, the living cells of the tissue.
Connective tissues are made of different combinations of ground substance and fibers. As you compare slides of connective tissues, which would most likely be the strongest (toughest) type of connective tissue based on the composition of ground substance and fibers? connective tissue high in ground substance connective tissues high in collagen fibers connective tissue high in elastic fibers connective tissue high in reticular fibers
connective tissues high in collagen fibers Collagen is the toughest of the fibers. If you saw collagen in high amounts, that would indicate strength in the connective tissue.
Which of the following is NOT a characteristic of nervous tissue? provides support and insulation highly branched cells creates linings capable of transmitting electricity
creates linings Epithelial tissue forms the body's linings and coverings.
Which of the following is a dry membrane exposed to the air? cutaneous membrane synovial membrane mucous membrane serous membrane
cutaneous membrane The cutaneous membrane is your skin, an organ consisting of a keratinized stratified squamous epithelium (epidermis) firmly attached to a thick layer of connective tissue (dermis). Unlike other epithelial membranes, the cutaneous membrane is exposed to the air and is a dry membrane.
After a heart attack, fibrosis occurs at the site of cardiac muscle cell death. This reduces the efficiency of the heart's pumping activity because __________. 1. the undamaged cardiac muscle cells become fatigued from the energy expended during the healing process 2. fibrous connective tissue is incapable of contracting 3. fibrosis produces new cardiac muscle cells that are not as strong as the mature ones that died 4. the initial death of some cardiac muscle cells triggers a chain reaction in which progressively more and more neighboring healthy cells die
fibrous connective tissue is incapable of contracting Cardiac muscle contains sarcomeres, which allow for the tissue to contract when electrically stimulated. Fibrous connective tissue lacks these special contractile units.
Which property is most consistent in all connective tissues? 1. large amounts of ground substance 2. avascularity 3. greater amount of extracellular matrix compared to cellular content 4. large number of connective fibers
greater amount of extracellular matrix compared to cellular content Even in blood, the cellular portion is less concentrated than the plasma matrix that surrounds the blood cells.
The correct order of events in tissue repair, from first to last, is __________. regeneration, organization, and inflammation inflammation, regeneration, and organization inflammation, organization, and regeneration organization, inflammation, and regeneration
inflammation, organization, regeneration
Smooth muscle __________. is under involuntary control contains intercalated discs has long, cylindrical cells has striations
is under involuntary control Smooth and cardiac muscle are under involuntary control. Skeletal muscle is under voluntary control.
Which of the following substances would NOT be found in significant amounts in the extracellular matrix of the illustrated areolar connective tissue? elastin collagen proteoglycan keratin
keratin Keratin is a protein typically found in epithelial tissues, notably the superficial layers of the epidermis. Keratin would therefore not be found in significant quantities in the ECM of connective tissues.
Which of the following is not a manner in which any epithelial tissues or glands are classified? shape of the cells number of cell layers location where secretions are released
location Epithelia are not classified by their location. Epithelia are classified by their shape and layering. Glands formed by epithelia are named based on their number of cells, structure and type, and location of secretions.
Which of these terms applies best to all material in this tissue that is not cellular? mesenchyme interstitial fluid ground substance matrix
matrix The term matrix applies to all extracellular material seen, including the ground substance and all fibers.
Which of the following are INCORRECTLY paired? epithelium; endoderm, mesoderm, and ectoderm nervous tissue; ectoderm connective tissue; mesoderm muscle; endoderm
muscle; endoderm Muscle is derived from the mesoderm.
Which of the following glands might utilize the secretory mechanism and duct structure shown in A? pancreas sebaceous mucous thyroid See problem 21 Homework chapter 4
pancreas Merocrine glands, such as that shown in A, produce secretions such as saliva, sweat, and digestive enzymes.
What activity does cell 1 undertake to contribute to the body's defense against injury and infection? 1. differentiation to form red blood cells 2. secretion of chemicals that trigger inflammation 3. phagocytosis of foreign materials 4. synthesis of protein fibers used to rebuild damaged tissue
phagocytosis of foreign materials Cell 1 is a macrophage, which phagocytizes foreign materials such as bacteria and debris. It can be identified by its large size.
Under a microscope you observe a tissue that appears to have long fibers that appear striated. The nuclei are pushed off to the side of the fibers. The tissue looks very vascular. What type of tissue are you observing? osseous tissue dense regular connective tissue dense irregular connective tissue skeletal muscle tissue
skeletal muscle tissue The striations are evidence of the myofilaments inside skeletal muscle cells, also called muscle fibers. The position of the nuclei and vascularity are also signs of muscle tissue.
Which of the following epithelial tissue types is NOT correctly matched to its function? simple cuboidal epithelium; secretion stratified squamous epithelium; absorption simple columnar epithelium with microvilli; absorption simple squamous epithelium; filtration
stratified squamous epithelium; absorption Stratified squamous epithelium is thick and durable. It is found in the skin, where it provides protection from the external environment.
What function do transitional epithelia have? stretching resistance to friction filtration absorption
stretching Transitional epithelium is found in the urinary system. It lines the ureters, bladder, and proximal part of the urethra—organs that are subjected to distention or stretching as urine passes through or fills them.
What distinguishes the gland in A from the gland in B? 1. whether or not they secrete products into a duct 2. whether or not the secretory cells are considered epithelial or connective tissues 3. whether or not they secrete products into the blood 4. whether or not the secretory cells are destroyed in the process of secretion See problem 22 Homework chapter 4
whether or not the secretory cells are destroyed in the process of secretion The gland in A is secreting in a merocrine manner (exocytosis), while B is secreting in a holocrine manner (rupturing).
