P1 Structure List - Tissue Histology Flashcards
Epithelial Tissue
AKA Epithelium
Cells are arranged in sheets
Cells are densely packed
Many cell junctions are present
Epithelial cells attach to a basement membrane
Epithelial tissue is avascular but does have a nerve supply
Mitosis occurs frequently
Simple Squamous
(Epithelial Tissue)
Single layer
“tiled floor appearance”
Central nucleus, round
Locations: cardiovascular and lymphatic system (heart, blood vessels, lymphatic vessel linings), air sacs of lungs, bowman’s capsule of kidneys, epithelial layer of serous membranes, NOT found in areas of mechanical stress
Filtration, diffusion, secretion
Simple Columnar
(Epithelial Tissue)
Single layer, ciliated
Column-like
Nuclei near base, oval
Contain goblet cells
Locations: some bronchioles, uterine tubes, uterus, central canal of spinal cord, ventricles of the brain
Cilia beat in unison moving mucus and foreign particles
Moves mucus toward throat, moves oocytes expelled from ovaries
Simple Cuboidal
(Epithelial Tissue)
Single layer
“cube shaped”
Central nucleus, round
Locations: surface of ovary, anterior surface of lens of the eye, lines kidney tubules, ducts of glands
Secretion and absorption
Stratified Squamous (Keratinized)
(Epithelial Tissue)
2 or more layers
1st few layers are squamous, deeper vary from cuboidal to columnar
Cells die as they work their way up, slough off
keratinized: tough layer of keratin on top/apical layer
keratin: tough, fibrous, protects skin
Location: superficial skin
Protects, 1st line of defense against microbes
Stratified Squamous (Nonkeratinized)
(Epithelial Tissue)
2 or more layers
1st few layers are squamous, deeper vary from cuboidal to columnar
Cells die as they work their way up, slough off
nonkeratinized: consistently moistened by saliva/mucus glands
Location: mouth, esophagus, pharynx, vagina, tongue
Protects, 1st line of defense against microbes
Psuedostratified (ciliated) Columnar
(Epithelial Tissue)
Single layer, but APPEAR to have multiple layers
Column-like, come cells do NOT extend to apical surface
Nuclei at various levels
Ciliated: cilia, goblet cells
Nonciliated: NO cilia, NO goblet cells
Locations: airways of upper respiratory tract, nonciliated line ducts of glands, epididymus, part of male urethra
Ciliated: secrete mucus, sweep mucus away for elimination
Nonciliated: absorption and protection
Transitional
(Epithelial Tissue)
Relaxed and stretched state
Apical layer usually large and rounded
Cells become flatter when stretched
Multiple layers, elastic
Location: hollow structures subject to expansion: urinary bladder,
ureters (portion of them), and urethra
Allows organs to stretch and maintain protective lining, hold large amounts of fluid without rupturing
Connective Tissue
protects and supports the body and its organs. Various types of connective tissues bind organs together, store energy reserves as fat, and help provide the body with immunity to disease-causing organisms.
Areolar
(Connective Tissue)
Most widely distributed
Collagen, elastic, reticular fibers
Location: in and around every body structure, known as:
PACKING MATERIAL OF THE BODY
Strength, elasticity, support
Adipose
(Connective Tissue)
Adipocytes
Store triglycerides
Large central droplet
Nucleus pushed to periphery
Location: everywhere areolar tissue is, deep to skin, around heart and kidneys, padding around joints, behind eyeball in socket
Reduces heat, energy reserve, protects organs
Dense Regular
(Connective Tissue)
Forms shiny white extracellular matrix
Mainly collagen fibers- regularly arranged in bundles with fibroblasts in
rows between them
Location: tendons, ligaments, aponeurosis (sheet-like tendons)
Provides strong attachment between various structures, withstands
pulling tension along long axis of fibers
Hyaline Cartilage
(Connective Tissue)
Contains resilient gel as ground substance, bluish-white in the body, shiny
Fine collagen fibers not visible
MOST abundant cartilage
Surrounded by perichondrium except in places where bones lengthen
Location: ends of long bones, anterior ends of ribs, nose, parts of larynx, trachea, bronchi, bronchial tubes, embryonic and fetal skeleton
Provides smooth surface for movement of joints, flexibilty and support
WEAKEST, can be fractured (growth plate fracture)
Bone
(Connective Tissue)
Description: Compact bone tissue consists of osteons that contain lamellae, lacunae, osteocytes, canaliculi, and central canals. By contrast, spongy bone tissue consists of thin columns called trabeculae.
Skeletal system: cartilage, joints, bones
Bones are made up of osseous tissue
Blood
(Connective Tissue)
Description: Blood plasma and formed elements: RBC (erythrocytes), WBC (leukocytes), platelets (thrombocytes).
Location: Within blood vessels (arteries, arterioles, capillaries, venules, veins), within chambers of heart.
Function:
RBCs: transport oxygen and carbon dioxide
WBCs: involved in phagocytosis, immunity, allergic reactions
Platelets- participate in blood clotting
Muscular Tissue
composed of cells specialized for contraction and generation of force. In the process, muscular tissue generates hear that warms the body.
Skeletal
(Muscle Tissue)
Long, cylindrical, striated
MULTINUCLEATED
Nuclei in periphery
VOLUNTARY control
Location: attached to bones via tendons
Motion, posture, heat production, protection
Cardiac
(Muscle Tissue)
Branched, striated
ONE CENTRAL nucleus
Attached by thickenings of plasma membrane: intercalated discs
they contain desmosomes and gap junctions
INVOLUNTARY control
Location: heart wall
Pumps blood to all parts of body
Smooth
(Muscle Tissue)
NONstriated, smooth
Taper at the ends: spindle shaped
Central, single nucleus
Can produce powerful contractions by contracting in unison
INVOLUNTARY control
Location: iris of eyes, walls of hollow internal structures
MOTION
Nervous Tissue
detects changes in a variety of conditions inside and outside the body and responds by generating electrical signals called nerve action potentials (nerve impulses) that activate muscular contractions and glandular secretions.
Neuron
(Nervous Tissue)
Nerve cells = neurons
Nerve action potentials: nerve cells convert stimuli into electrical signals
3 parts of neurons:
cell body: nucleus ad organelles
dendrites: highly branched, short processes, INPUT/RECEIVE Info
axon: single, thin, conducts nerve impulses
Other cells: called neuroglia
Location: nervous system
Convert stimuli into nerve impulses (action potentials)
