Ch.4 Histolgy Flashcards
Tissue
Group of cells similar in structure that preform common or related function
Histology
Study of tissues
STRUCTURE = FUNCTION!!!
4 types of primary tissues
- Epithelial tissue
- covers - connective tissue
- supports - Muscle tissue
- produces movement - Nerve tissue
- controls
Epithelial tissue (epithelum)
Is a sheet of cells that covers a body surface or lines a body cavity. Epithelia form boundaries between different environments.
Two forms of epithelial tissue that are found in the body
• Covering and lining epithelia
- on external and internal surfaces( ex. Skin lines urogenetal digestive and reproductive systems covers the walls and organs of the ventral body cavity)
• Glandular epithelia
- secretory tissue in glands
Two forms of epithelial tissue that are found in the body
• Covering and lining epithelia
- on external and internal surfaces( ex. Skin lines urogenetal digestive and reproductive systems covers the walls and organs of the ventral body cavity)
• Glandular epithelia
- secretory tissue in glands
6 major functions of epithelial tissue
- Protection
- Absorption
- Filtration
- Excretion
- Secretion
- Sensory reception
5 characteristics of epithelial tissue that distinguish it from other tissues
- Polarity
- Specialized contacts
- Supported by connective tissue
- Avascular but innervated
- Can regenerate
How is epithelial classified?
- The first indicates the number of cells
• simple epithelia = single layer of cells
• stratified epithelia = two or more layers of cells
- shape can change in different layers - The second indicates the shape of cells
• squamous
• cuboidal
• columnar
- in stratified epithelia, the epithelia is classified by the cell shape in apical layer
Simple squamous epithelia
-Single layer flattened (scale) like cells
- Allow materials to pass through by diffusion and filtration
- kidneys, air sacs of lungs, blood and lymphatic vessels, using of ventral bodycavity
Simple cuboidal epithelium
-Single layer of cube like calls
-Secretes and absorption
-kidney tubules, duct and secretory portions of , small glands, ovary surface
Simple columnar epithelium
-Single tall layer of cells
-absorption and secretion of mucus, enzymes and other substances
-noncilliated
• digestive tract ( stomach to rectum)
-ciliated
• bronchi, uterine tubes and uterus
Pseudostratified columnar epithelium
-Single layer of cell of different heights
- secretes substances (primarily mucos), propulsion by ciliary action
- nonnciliated
• male sperm carrying ducts, ducts of large glands - ciliated
• trachea, most of upper respiratory tract
Stratified squamous epithelium
- Two or more cell layers, thick membrane
- protects against abrasion
- nonkeratinized
•moist lining of the esophagus, mouth and vagina
-keratinized
•epidermis of skin
Transitional epithelium
-Resembles both stratified squamous and stratified cubical
• basal cells cuboidal or columnar
• surface cells dome shaped or squamous like depending on degree of stretch of organ
- stretches readily, permits stared urine to destined urinary organ
- lines the ureters, bladder, part of the urethea
Epithelial tissue types covered in class
-Covering and lining
-Glandular
Gland
Consists of one or more cells that makes and secretes aqueous fluid called a secretion
Epithelial tissue is avascular but innervated
True
Major function of simple squamous epithelia are filtration and diffusion
True
Simple cuboidal epithelium are found of in areas where secretion and absorption occur
True
Primary function of simple squamous epithelia is absorption and secretion of mucous enzymes and other substances.
False
Columnar
Primary function of stratified cuboidal epithelia is protection
False
squamous
Depending on the functional state of the bladder, the upper most layer of stratified columnar epithelium may look squamous or cuboidal
False
transitional
Simple columnar epithelia Iines most of the digest tract
True
Simple cuboidal epithelia are found in the kidney tubules
True
Keratinized stratified squamous epithelia forms the outer layer of the skin (epidermis)
True
Simple squamous epithelium forms the lining of hollow urinary organs
False
transitional
Many goblet cells are found within pseudostratfied ciliated columnar epithelium
True
Contrast exocrine and endocrine glands
Endocrine glands release their products (hormones) internally into extra cellular fluid
- they eventually make their way into the blood or lymph
Exocrine glands release their secretions onto a surface
-this can be an external surface such as the skin or internal surface such as the linen of the small intestine
The only important unicellular exocrine glands
Mucous and goblet cells
Most important multicellular glands
Sweat, oil, salivary, liver and pancreas
Exocrine primary modes of secretion
Merocrire
- secrete products by exocytosis
• pancreas, most sweet glands and salivary glands
Holocrine
- entire secretary cell ruptures releasing secretions and dead cell fragments
• oil (sebaceous) glands of the skin
List 5 examples of exocrine glands
Sweat glands
Pancreas
Salivary glands
Sebaceous (oil) glands
Liver (bile)
Glands that secrete their products by exocytosis as they are produced
Merocrine
Gland which accumulate products within, then rupture
Holocrine
Sweat glands are an example of this type of gland
Merocrine
Sebaceous glands are an example of this type of gland
Holocrine
The pancreas is an example of this type of gland
Merocrine
Connective tissue
Most abundant and widely distributed of the primary tissues; though its amount in different organs varies
Four main classes of connective tissue
- Connective tissue proper
- Cartilage
- Bone
- Blood
Major functions of connective tissue
- Binding and support (ex. ligaments end tendons)
- Protecting (ex. areolar)
- Insulating (ex. adipose)
- Storing reserve fuel ( ex. adipose)
- Transporting substances (ex. blood)
3 characteristics that differentiate connective tissue from other tissues
- Common origin (a.ll connective tissue arse from embryonic tissue)
- Varying degree of vascularity (blood vessels) from no vascularity in cartilage to highly vascularized areolar tissue
- All connective tissue have an extracellular matrix
• connective tissue not composed mainly of cells but largely non-living extracellular matrix which separates cells
- this allows tissue to bear weight,withstand tension, endure abuse such as physical trauma
3 structural elements of connective tissues
- Ground substance
- Fibers
- Cells
Ground substance
Is the unstructured material that fills the space between cells
- medium through which solutes diffuse between blood and capillaries and cells
- made of interstitial fluid cell adhesion proteins (“ glue” for attachment) and proteoglycans ( protein core + large polysaccharides)
-the proteoglycans trap water and varying amounts affecting viscosity of ground substance (the higher, the concentration of proteoglycans), the thicker more viscous the ground substance)
Connective tissue fibers (3)
Three types of fibers provide support:
-collagen
• strongest, and most abundant
• Tough, high tensile strength
-elastic fibers
• network of long, thin, elastin fibers that allow for stretch and recoil
• reticular
• short fine highly branch collagenous, fibers (different chemistry, and formed in collagen fibers)
• Branching networks that offer more “give”
Connective tissues cells. “Blast”
“blast”-immature cells are myopically, active cells that secrete ground substance, and the fiber characteristic of that tissue type
“blast” cells found, and connective tissue classes
•fibroblasts and connective tissue proper
• chondroblast in cartilage
• osteoblast in bone
• Hematopoietic stem cells in bone marrow
Connective tissues cells. “Blast”
“blast”-immature cells are myopically, active cells that secrete ground substance, and the fiber characteristic of that tissue type
“blast” cells found, and connective tissue classes
•fibroblasts and connective tissue proper
• chondroblast in cartilage
• osteoblast in bone
• Hematopoietic stem cells in bone marrow
Connective tissue cells “ cyte”
• once they synthesize the matrix the “blast” Sal, assume their mature less active role and are indicated by the suffix “Cyte”. They can revert to active state if repairs are needed.
“Cyte” cells:
- adipocytes un adipose tissue
• Fibrocytes in connective tissue proper
• chondrocytes in cartilage
• osteocytes in bone
What is extra cellular matrix made of
Fibers and ground substance
The following is a true statement about dense regular connective tissue
It contains many collagen fibers running in the same direction
The fiberglass is the primary cell type within it
For tendons and ligaments
For tendons and many of the ligaments
It has a high tensile strength
Cells found in areolar connective tissue include:
-chondrocytes
-fibroblasts
-macrophages
Types of connective tissue proper
• connective tissue proper includes all connective, tissues, except bone, cartilage, and blood
• Two subclasses of connective tissue proper:
-Loose connective tissues
•areolar
•adipose
•reticular
-dense connective tissue
• dense regular
• dense irregular
• Elastic
Loose connective tissue
areolar
• Gel like matrix, all three fiber types (collagen elastic and reticular fibers)
• fiber, blast, microphobia mass cells and WBCs
• Wraps and cushions organs important roll and inflammation, holding convey tissue fluid
• Skin, packages organs, surrounds blood and lymph vessels
Loose connective, tissue
Adipose
• Very sparse matrix, closely packed adipocytes
• Reserve, food, fuel, insulate support, and protects organs
• Subcutaneous, tissue, kidneys, eyeballs, abdomen, and breasts
Loose connective tissue
Reticular
• Network of reticular fibers, reticular cells produce the reticular fibers that formed the network onto which other cells attach
• supportive framework for soft organs, WBCs, mast cells, and macrophages
• lymphatic, tissue, spleen, liver, and bone marrow
Dense connective tissue
Dense regular
• Parallel, dense, elastin, and collagen fibers
• fibroblast
• can strength attaches muscle to bone and bone to bone
• tendons and most ligaments
Dense connective tissue
Dense irregular
• the direction of fiber are random mesh like network
• fibroblast
• tensile tension in all directions structural strength arterial walls
• skin dermis, fibrous capsules of organs and joints and digestive track
Dance connective tissue
Dense irregular
• the direction of fiber are random mesh like network
• fibroblast
• With tension and all direction structural strength arterial walls
• skin dermis, fibrous capsules of organs and joints and digestive tract
Dense connective tissue
Elastic
• dense regular connective tissue containing a high proportion of elastic fibers
• allows tissue to recoil after stretching, pulsitile flow of blood and passive recoil of lungs
• Large arteries, certain ligaments, vertebral column, bronchial tubes
Cartilage
• withstand, both compression and tension has qualities immediate
It is tough yet flexible.
• nerves, and fiber and is avascular
-Receive nutrients from membranes
surrounding it
• It’s ground substance contains a high percentage of proteoglycans (=viscous)
• contains (primarily) collagen and sometimes elastin fibers
• 80% water, allowing rebound after compression
• chondroblast are the predominant cell type in growing Cartlidge until growth stops —> chondrocytes
Cartilage
Hyaline
•amorphous (without a clearly defined shape) but firm matrix and collagen fibers
• chondroblast
• support and reinforces, cushion resists compressive stress
• embryonic skeleton, ends of long bones, coastal cartilage ribs, nose, trachea and larynx
Cartilage
Elastic
• Elastic fibers collagen, and proteoglycans
• shape and strength while allowing flexibility
• ear (pinna) and epiglottis.
Cartilage
Fibrocartilage
• thick bundles of collagen fibers
• tensile strength allows it to absorb compressive shock.
• intervertebral discs and menisci in the knee
Cartilage
Fibrocartilage
• thick bundles of collagen fibers
• tensile strength allows it to absorb compressive shock.
• intervertebral discs and menisci in the knee
Membrane
• selective barrier that allows the passage of materials and prevents others
• Typically an epithelium bound to underlining connective tissue proper
Cutaneous membrane
• Skin
• keratinized squamous epithelium (epidermis) attached to thick layer of connective tissue (dermis).
• it’s function is protection
Mucus membranes names by location
• closed ventral body cavity
- pleura (lungs)
- pericardium (heart)
- pertinoneum (Abdominopelvic)
* reduce friction between organs
Strongest and most abundant type of fiber provides high tensile tension
Collagen
Short fine, highly branch collagenous fibers; forming networks that offer more “give”
reticular fibers
Forms networks of long, thin, elastin fibers that allow for stretch and recoil
Elastic fibers
Connective tissue is differentiated from other tissues by the presence of an extracellular matrix matrix
True
Collagen fibers are the most abundant fiber type in connective tissues
True
Areolar connective tissue is the most widely distributive connective tissue
True
Dense regular connective tissue is the “universal packaging material”
False
Areolar
Areolar connective tissue contains all three fiber types
True
The primary function of reticular connective tissue is shock absorption, insulation, and energy storage
False
Adipose
Adipose connective tissue is unusual and that it has a high number of cells found within
True
Areolar connective tissue forms the internal stoma of soft organs, such as lymph nodes, the spleen and bone marrow
False
Reticular
Irregular connective tissues contain closely packed bundles of fiber, running in the same direction
False
Regular
Dense regular connective tissue has thick bundles of irregularly arranged, collagen fibers
False
Irregular
Dense, irregular, connective tissue makes up the fibrous coverings of some of the organs (kidneys, bones, muscles, and nerves)
True
Dense irregular, connective tissue provide structural strength and withstand tension exerted in many directions
True
Dense irregular connective tissue provides structural strength and withstands tension exerted in many directions
True
Tendons and ligaments are composed, mainly of dense, regular connective tissue
True
Connective tissue contains other cells, including fat cells, white blood cells, macrophages, and simple squamous epithelium
False
Elastic connective tissue is found in the walls of the large arteries that leave the heart
True
Bone and Cartlidge are similar in composition, except bone contains more collagen in addition to inorganic mineral salt, which provide hardness
True
A membrane that lines body cavities closed to the external environment
Serous membranes
Membranes that line the body cavities open to the external environment are
Mucus membranes
Membranes that line the body cavities open to the external environment are
Mucus membranes
The skin is a
Cutaneous membrane
Match the drawing above with the tissue type listed below
