Histology (Embryo) Exam 4 Final

The study of tissues of the body

Histology

Major components of tissues

cells, ECM

Functions of interstitial fluid

transport nutrients to cells, remove waste from cells, transport secretory products from cells

Basic tissue type that supports the body and holds it together

connective tissue

Basic tissue type that functions in secretion, absorption, and exercise

epithelial tissue

Basic tissue type that specializes in contraction and movements

muscle tissue

Basic tissue type that specializes in communication between various body structures and control and integration of their activities

nervous tissue

Process of removing a tissue sample during medical procedures/surgery

biopsy

What is done to a biopsy if results are needed rapidly during surgery?

biopsy is frozen using liquid nitrogen

Types of epithelial tissue

covering/lining, glandular

T/F epithelial tissue arises from all 3 germ layers (mesoderm, ectoderm, endoderm)

true

T/F epithelial tissue functions in attachment and support

false

Function of epithelial tissue

protection, sensory, secretion, absorption, excretion

Characteristic of epithelial tissue

very small amount of ECM

A noncellular layer attaching epithelial tissue to underlying connective tissue

basement membrane

Is the basement membrane permeable?

yes

Is epithelial tissue vascularized?

no

Connective tissue than lies deep to basement membrane of epithelium lining respiratory, digestive, and urinary systems

lamina propria

T/F the lamina propria contains smooth muscle, blood vessels, and glands

true

Flat, plate-like cells

squamous epithelium

Cube-shaped cells

cuboidal epithelium

Taller, narrow, cylindrical cells

columnar epithelium

Parts of an epithelial cell

apical pole, basal pole

Which pole faces a cavity or space?

apical pole

Which pole rests on the basement membrane?

basal pole

Single layer of epithelial tissue

simple epithelium

Multiple layers of epithelial tissue

stratified epithelium

Type of epithelial tissue found in alveoli of lungs, endothelium (lining of blood and lymph vessels), and mesothelium (membranes covering organs and body wall

simple squamous epithelium

Type of epithelial tissue found in glands, ducts, and kidney tubules

simple cuboidal epithelium

Type of epithelial tissue found in stomach, intestines, uterus, uterine tubes, and parts of respiratory system

simple columnar epithelium

Specialized structure of simple columnar epithelium that is long, microscopic hairlike processes which move material along

cilia

Specialized structure of columnar epithelium that contains large secretory vesicles which produce mucus

goblet cells

Specialized structure of columnar epithelium that increases surface area of mucosa for absorption

microvilli

Specialized structure of columnar epithelium that is absorptive in function but are much longer than microvilli

stereocilia

Specialized structure of columnar epithelium that are microscopic hairlike processes which move material along

cilia

Type of epithelial tissue found in respiratory air passages (nasal cavity, trachea, bronchi) and the male reproductive system

ciliated pseudostratified columnar epithelium

Type of epithelial tissue found in epidermis

stratified keratinized squamous epithelium

Protein found in skin, hair, and nails

keratin

Type of epithelial tissue found on moist surfaces, like mouth, pharynx, esophagus, and vagina

stratified non-keratinized squamous epithelium

Type of epithelial tissue found in sweat gland ducts and ovarian follicles

stratified cuboidal epithelium

Type of epithelial tissue found in male urethra

stratified columnar epithelium

Type of epithelial tissue found in ureters and urinary bladders that have a number of observable cell layers that decrease with stretch

transitional epithelium

Classification of glandular epithelium that are either short or long and coiled

tubular

Classification of glandular epithelium that are rounded or saclike

acinar

Gland that secretes product into ducts that open into a hollow organ

exocrine glands

Sweat glands, salivary glands, and digestive glands of the stomach and pancreas are examples of:

exocrine glands

Gland that secretes product directly into the bloodstream

endocrine glands

Pituitary, thyroid, parathyroid, and suprarenal glands are examples of:

endocrine glands

A secretory product of exocrine glands that destroys the cell to release it

holocrine

Sebaceous glands are an example of what product of exocrine glands?

holocrine

Mammary glands are an example of what product of exocrine glands?

apocrine

A secretory product of exocrine glands that secrete through cell membrane without damaging the cell (most secretory cells)

merocrine

Salivary glands are an example of what product of exocrine glands?

merocrine

Intercellular junction that forms a seal between adjacent cells

tight/occluding junctions

Intercellular junction that are sites of strong cell adhesion found below tight junctions

adherens junctions

Intercellular junction that anchors by forming a single spot-weld

desmosomes

Intercellular junction that are channels for communication between cells

gap junctions

Intercellular junction that attaches cells to basal lamina and resemble half of a desmosome

hemidesmosome

What tissue type consists mainly of ECM with few cells?

connective tissue

T/F connective tissue derives from endoderm and surface ectoderm

false

What germ layers does connective tissue derive from?

mesoderm, neural crest cells

Functions of connective tissue

attachment, supporting framework for the body, transport, defense

What are the most common cells of connective tissue?

fibroblasts

Fibroblasts secrete…

collagen, elastin, and all ground substance components

Another function of fibroblasts

tissue repair

Fat cells of connective tissue

adipocytes

Cell type of connective tissue that removes cellular debris, neoplastic cells, bacteria and other invaders

macrophages

Cell type of connective tissue that release mediators of inflammation (e.g. histamine)

mast cells

Cell type of connective tissue that produce antibodies (lymphocyte derived)

plasma cells

T/F fibroblasts, macrophages, mast cells, plasma cells, and other leukocytes are native to connective tissue

false

Where are fibroblasts, macrophages, mast cells, plasma cells, and other leukocytes formed originally?

bone marrow

In hay fever/allergies, what cell releases histamine which increases permeability of blood vessels in the nasal cavity?

mast cells

Process where large amounts of leukocytes pass through blood vessel walls into injured tissue

chemotaxis

Attraction of cells by specific chemicals (I.e. inflammation)

chemotaxis

Components of ECM

fibers, ground substance

Major component of fibers in ECM

protein collagen

Most abundant type of collagen which resists tension

type I collagen

Collagen type found in cartilage

type II collagen

Collagen type found in muscle, blood vessels, and lymphatic system

type III collagen

Collagen type found in basal laminate which functions in filtration

type IV collagen

Fiber type formed of type I collagen bundles

collagen fibers

Fiber type that is delicate and formed of type III collagen

reticular fibers

Fiber type formed of protein called elastin (only one not made from collagen)

elastic fibers

A highly hydrated, gel-like substance found in ECM

ground substance

Function of ground substance

allows diffusion of molecules, lubricant, barrier to infection

Part of ground substance that are made up of polysaccharide chains

GAGs

Most abundant GAG

hyaluronic acid

Part of ground substance consisting of a core protein with various GAGs bound

proteoglycans

Embryonic mesenchyme contains large amounts of…

hyaluronan, water

Why is embryonic mesenchyme ideal for cell migration and growth?

it produces a wide space of cells

Most widely distributed connective tissue type

loose (areolar) connective tissue

Which CT type contains cells, fibers, and ground substance in roughly equal amounts and has a delicate consistency?

loose (areolar) connective tissue

Which CT consists primarily of densely packed collagen fibers formed of type I collagen

dense connective tissue

Which CT is found in most of dermis of skin, in deep fascia, and in the capsule of organs (e.g. kidney or spleen)?

dense irregular connective tissue

Which CT is found in tendons, aponeuroses, and ligaments and resists stress in one direction?

dense regular connective tissue

CT type that is net or mesh-like tissue that functions as a filter

reticular tissue

What cell type does tissue repair depend on?

fibroblasts

What kind of fibroblast behaves like smooth muscle?

myofibroblasts

Methods discussed in class that can determine body composition

skin fold thickness, hydrostatic weighing

Most accurate method of determine body composition

hydrostatic weighing