Histology Flashcards
Simple squamous epithelium
description, function, location
D: single layer of flattened cells
F: diffusion and filtration
L: air sacs of lungs, kidney, blood vessels(endothelium)
Simple columnar epithelium (ciliated type and nonciliated)
D: single layer of tall cells w/ round-oval nuclei, can bear microvilli or cilia, can contain goblet cells
F: absorption and secretion, ciliated type propels mucus by ciliary action
L: nonciliated type lines digestive tract (stomach-rectum)
ciliated type lines small bronchi
Simple cuboidal epithelium
D: single layer of cubelike cells w/ large spherical nuclei
F: secretion and absorption
L: kidney tubules and glands
Pseudostratified columnar epithelim (ciliated type and nonciliated)
D: single layer of cells of differing heights, nuclei seen at different levels, may contain goblet cells and bear cilia
F: secretion and propulsion of mucus
L: ciliated type lines upper respiratory tract,
nonciliated type in males’ sperm carrying ducts and ducts of large glands
Stratified squamous epithelium (nonkeratinzed type and keratinzed type)
D: composed of several layers, surface cells are flattened (squamous)
F: protects underlying tissues subjected to abrasion
L: nonkeratinzed type forms moist linings of the esophagus, mouth, and vagina
keratinzed type forms epidermis of the skin
Stratified cuboidal epithelium (rare)
D: typically two cell layers thick
F: absorption and secretion
L: quite rare, found in some sweat and mammary glands
Transitional epithelium
D: several cell layers, basal cells are cuboidal/columnar, surface cells are dome shaped
F: stretches readily to permit the distension of the urinary bladder
L: lines urinary bladder, ureters, part of urethra
Endocrine release
internally secreting, i.e. hormones into bloodstream
Merocrine mode of secretion (exocrine type)
secrete their products by exocytosis, cell stays intact
i.e. sweat glands: eccrine(directly onto skin) and apocrine(hair )
Exocrine release
externally secreting, i.e. sweat onto epidermis, mucous, salivary glands
Holocrine mode of secretion (exocrine type)
entire secretory cell ruptures, releasing secretions and dead cell fragments
i.e. sebaceous gland of the skin
Apocrine mode of secretion (exocrine type)
part of apical portion pinches off and leaves duct
i.e. mammary glands
Types of CT
bone, blood, cartilage, connective tissue proper
Types of fibers in CT
collagen, elastic, reticular
Functions of CT
binding and supporting, protecting, insulating, storing reserve fuel, transporting
Collagen fiber
provides high tensile strength
Elastic fiber
long, thin fibers that allow for stretch
Reticular fiber
branched collagenous fibers that form delicate networks
Fibroblast is in which CT?
CT proper
Chondroblast is in which CT?
cartilage
Osteoblast is in which CT?
bone
Hematopoietic stem cells are in which CT?
blood
CT proper: loose, areolar
D: gel-like matrix with all three fiber types
F: wraps and cushions organs
L: packages organs
Common origin of all CT is
mesenchyme; an embryonic CT
CT proper: loose, adipose
D: closely packed adipose “bubbles” (cells), or adipocytes; nucleus pushed to the side
F: provides reserve food fuel, insulates against heat loss, supports and protects organs
L: subcutaneous tissue, around kidneys and eyeballs, within abdomen, in breasts
CT proper: loose, reticular
D: network of reticular fibers, reticular cells lie on network
F: form a soft internal skeleton (stroma) that supports other cell types like WBCs, mast cells, etc.
L: lymphoid organs
CT proper: dense, dense regular
D: parallel collagen fibers, few elastic fibers, primarily fibroblasts
F: attaches muscle to bone or bone to bone
L: tendons(muscle to bone) and ligaments(bone to bone)
CT proper: dense, elastic
D: dense regular CT containing HIGH proportion of elastic fibers, (compacted bacon), tightly packed boobs
F: recoiling, pulsatile flow of blood
L: walls of arteries, within ligaments
CT proper: dense, dense irregular
D: irregularly arranged collagen fibers, primarily fibroblasts, LOOKS LIKE TIE DYE!
F: withstands tension, provides structural strength
L: fibrous capsules of organs and of joints
CT: cartilage, hyaline
D: chondrocytes lie in lacunae within matrix, “half jellies”
F: supports and reinforces, cushion
L: covers end of long bones, cartilage in ribs, nose, trachea, larynx, etc.
CT: cartilage, fibrocartilage
D: similar to hyaline cartilage but thick collagen fibers predominate, “very tiny jellies, mostly strings” ,streaming river
F: absorb compressive shock
L: intervertebral discs
CT: cartilage, elastic
D: same as hyaline cartilage but more elastic fibers in matrix
F: maintains shape of structure with great flexibility
L: external ear and epiglottis
CT: bone
D: circular lacunaes “it look like wood”
F: supports and protects, blood cell formation
L: bones (duh)
CT: blood
D: red and white blood cells in plasma matrix
F: transport respiratory gases, nutrients, etc.
L: contained within blood vessels
Skeletal muscle
D: very obvious cylinder separations and very obvious striations, multinucleate
F: voluntary movement i.e. walking
L: skeletal muscles attached to bones or occasionally to skin
Cardiac muscle
D: branching, slightly striated, uninucleate cells, intercalated discs
F: involuntary, propels blood into circulation
L: walls of heart
Smooth muscle
D: no striations, cells closely together to form sheets
F: propels substances/objects along internal passageways (urine, a baby, etc.), involuntary control
L: mostly in the walls of hollow organs i.e. intestines, stomach
Nervous tissue
D: neurons (very obv to distinguish)
F: transmit electrical signals
L: brain, spinal cord, nerves
Types of cells in CT
osteoblast, chondrocyte, fibroblast
