- Major resident cells of bone

- Differentiate into bone lining cells and osteocytes

- Produce osteoid around themselves as they become osteocytes

- Completely surrounded by bone

- Reside in lacunae

- Capable of producing osteoid and resorbing bone (osteocytic osteolysis)

- Connect to adjacent osteocytes via cell processes and gap junctions

• cell processes extend through canaliculli
• processes act as cell receptors of bone (detect stress)

- Single layer of squamous cells

- Quiescent osteoblasts

- Retain gap junction connections

- Produce an ion-barrier between bone and surrounding tissue

- Partially undifferentiated stem cells

- Can become osteoblasts to result in bone formation

- Found in cellular periosteum, in bone marrow cavity adjacent to endosteum, and within Haversian Canals

-Specialize in bone resorption

-Arise from monocyte progenitors

- Anti-resportive surface: High in Cl-/HCO3- exchangers and adjacent to capillaries

- Howship's lacunae/resorption tunnels: Ruffled border

- Parathyroid Hormone --> osteoclast-stimulating factor from osteoblasts --> increased osteoclast activity

- Responds directly to calcitonin --> inhibits

- Bone produced without a pre-existing cartilage model

- Bone blastema --> condensation of mesenchymal cells

- Primary bone formed

- Grows more rapidly

- Less mineralized and more cellular

- Secondary bone 

- Less cellular and more mineralized

- Grows less rapidly

- Much stronger 

- Distinct lamellae present

1. Primary cartilage model formed by chondroblasts

2. Hypertrophy of chondrocytes in center of growing cartilage model

3. Development of Type X collagen from Type II collagen

4. Formation of bone collar between periosteum and the shaft of cartilage model

5. Cartilage matrix calcification--> apoptotic death of chondrocytes

6. Small clusters of blood vessels infiltrate as periosteal bud

7. Osteoprogenitor cells and hematopoietic cells produce primary ossification center

8. Bone matrix laid down ontop of calcified cartilage model

9. Secondary ossification sites appear later on in life

- Alteration of size and shape of bone by simultaneous bone growth and resorption on opposite surfaces of bone

- Via simultaneous activity of osteoblasts and osteoclasts

- Replacement of old woven bone with new lamellar bone

- Occurs in a specific cycle

1. Osteoclasts drill a large resorption tunnel into bone. Osteoclasts form cutting cone.
2. Osteoclasts disappear and osteoblasts differentiate from osteoprogenitor cells, begin to form osteoid
3. Bone forms from outer wall inwards toward center of tunnel
4. Bone forms concentrically to form lamellae and osteoblasts become bone lining cells

1. A blood clot forms initially and becomes infiltrated by osteoprogenitor cells

2. Bone begins to form from osteoblasts from osteoprogenitor cells

3. In other areas a cartilage model is formed first and endochondral ossification continues

4. First bone is woven bone and forms a callus

5. Woven bone replaced by lamellar bone and the callus degraded down to produce original diameter of bone

- large sinusoidal capillaries

- composed of cords of parenchymal cells

• chromophobes
• acidophils
• basophils

- Basophils secrete melanocyte- stimulating hormone (MSH)

- Area between neurohypophysis and pars distalis

- Corticotrope: ACTH producing

- Thyrotrope: TSH producing

- Gonadotrope: FSH and LH secreting

- PAS-positive

- Somatotrope: Growth Hormone secreting

- Mammotrope: Secretes prolactin

- No glandular cells

- Modified neuronal cells

- Axons of hypothalamic neurons

- Secrete ADH and oxytocin from supraoptic and paraventricular neurons

- Neuroglial cells of pars nervosa 

- Extensions surround secreting axons (Herring bodies)

- From superior hypophyseal arteries

- Primary capillary plexus around infundibular stalk

- Secondary capillary plexus within pars distalis

- Aldosterone producing via pregnenolone precursor

- Small compact cells arranged in clumps

- Outermost layer of adrenal cortex

- Controlled by RAA system and ANP

- Finely vacuoled cytoplasm

- Cortisol producing cells

- Cells with eosinophilic cytoplasm arranged in cords

- Weak-Androgen producing cells

- Contain lysosomes and lipofuscin

- Under control of ACTH (corticotropes)

- Modified neuronal cells

- Chromaffin cells: Secrete epinephrine and norepinephrine

- Arranged in cellular cords around medullary sinuses

- Under sympathetic control

- Two capsules (External and Internal)

- Follicles: Follicular cells surrounding colloid (thyroglobulin) 

- Follicular epithelium: simple squamous to cuboidal depending on activity

- Iodine incorporated with thyroglobulin to produce colloid

- Colloid droplets endocytosed to produce T3 and T4 when thyroid gland activited

- Under control of TSH production from pituitary

- Autoimmune disease where autoantibodies are produced against TSH receptors

- Autoantibodies bind in absence of TSH and produce hyperthyroidism

- Causes goiter (inflammation of thyroid) and bulging of the eyes (exophthalmos)

- Autoantibodies target thyroid peroxidase and thyroglobulin

- Destroys thyroid follicles

- Hashimoto's Disease

- Derived from neural crest cells

- Located in clusters in the follicular walls

- Produce calcitonin

- Basally localized grey granules in lead-hematoxylin

- Two per thyroid lobe (four in total): surrounded by capsule

- Principal Cells: Relatively large nucleus with agranular cytoplasm, secrete parathyroid hormone

- Oxyphil Cells: Small dark nucleus with eosinophilic cytoplasm

- Alpha (A) Cells: Glucagon secreting

- Beta (B) Cells: Insulin secreting

- Delta (D) Cells: Secrete somatostatin to inhibit somatotropes, inhibit A and B cells too

- F Cells: Pancreatic polypeptide, inhibits pancreatic secretions

- Neuroendocrine Cells

- Amine-Precursor Uptake and Decarboxylation (APUD) Cells

- Epithelium continuous with corneal epithelium

- Covers the visibile part of sclera

- Thin mucous membrane of stratified columnar epith.

- Lines inner eyelid

- Goblet cells produce mucus to lubricate cornea

- Plate of CT in eyelid

- Provides stiffness to lid

- Contains tarsal glands

- Meibomian sebaceous glands

- 12-30 in upper lid

- Help produce lubricant layers for eye

- Skeletal muscle of upper lid

- Opens eyelid

- Follicles for cilia/eyelashes

- Loose and devoid of fat

- Ciliary Glands of Zeis: produces oily layer to prevent tear evaporation

- Junction of thin non-sensory retina and thick sensory retina

- Near ciliary body

- Ciliary muscle is spinchter

- Connects to lens via zonules of Zin

- Relaxed muscle--> zonules taught--> lens elliptical

- Near--> curved lens --> contracted muscle

- Far --> elliptical lens --> relaxed muscle

- Hardening of lens due to build up of lens fibers

- "old eye" --> normal aging of lens

- 2,000-3,000 lens fiber cells without nuclei

- Anterior surface epithelium --> contains stem cells

- Thick basement membrane

- Transparent due to crystallins

- Highly innervated

- Transparent C.T. layer due to lack of fluid

- Five layered epithelium

  1. Epithelium (5-6 Layers)

  2. Bowman's Membrane

  3. corneal stroma with collagen

  4. Descemet's Membrane

  5. Endothelium

- Colored portion of eye --> spongy stroma with melanocytes

- Surrounds pupil

- Determines how much light enters the pupil

- Smooth muscle sphincter --> constriction

- Diffuse dilator muscle

- epithelium continuous with retina (embryologically)

1. ciliary muscle and zonules

2. ciliary epithelium produces aqueous humor

- Blockage in drainage of aqueous humor --> open or closed angle

- Increased intraocular pressure results

- Embryologically from mesenchyme

- Pigmented cells

- Isolate retinal neurons from blood

- Phagocytose membrane shed by photoreceptors

- Reduces light scatter

- Choroid artery vasculature

- Five layered structure

  1. Nerve fiber layer

  2. Ganglion cell layer

  3. Inner plexiform layer

  4. Inner nerve layer

  5. Outer plexiform layer

  6. Photoreceptor layer

- Vasculature from retinal artery

- Specialization of the retina --> Center of gaze

- Thin layers except packed with cones

- Very color sensitive

- Retina thins to a "pouch"

- Ganglion cell layer thins

- Contains Henle Fibers

- Ganglion cell layer is very thick on either side of fovea

- Enters retina at optic disc via lamina cribosa

- Unmyelinated to myelinated in optic nerve

- Blindspot in vision

- Carries central retinal artery and vein

- Embryological outpouching of diencephalon

- Becomes retina and optic nerve as neuroblastic zone

- Forms optic cup, ciliary body epithelium and pigmented layer of iris

- Ectodermally derived

- Ectoderm thickens --> lens placode --> invaginates to form lens vesicle

- Indented structure of C.T.

- Contains renal sinus/pelvis

- Where vessels and nerves enter and exit and where ureter originates

- Outer darker staining region of kidney

- Lobed

- Contains glomeruli and Bowman's capsule, P.T., thick descending, TAL, distal tubule, and collecting ductules

- Mostly cortical nephrons

- Extensive vasculature (arterioles and peritubular caps)

- Lighter staining inner region of kidney

- Thin limb and collecting ducts

- Vasa recta

- Medullary/renal pyramids --> Feed into renal papilla

- Epithelium lined dense C.T.

- Urine collection from collecting ducts

- Feeds into major calyx --> ureter via renal pelvis

- Capped by cortex and core of medulla

- Renal column --> Cortex extending to minor calyx

- Justamedullary cortex --> Cortex right next to medulla

- Separated by renal columns

- Set of nephrons flowing into one collecting duct

- Medullary rays --> collecting duct extending into cortex

- Interlobular vessels

- Loose C.T. interstitium

- Small stellate veins near capsule

- Central renal art --> interlobar --> arcuate --> interlobular --> afferent arteriole --> glomerulus --> efferent arteriole --> peritubular/vasa recta --> venule

- Originates in renal sinus/hilar region

- Transitional epithelium

- Lamina propria/ submucosa (very thin musc mucosae)

- Muscularis Layer (2-3 layers): long and circ

- Adventitia: retroperitoneal organ

Relaxed: Mucosal folds w/ transitional epith., muscularis and serosa

Distended: No folds, extended epith., shrinkage of muscularis, and serosa

- Lots of elastin and type I and III collagen in L.P.

- Functional unit of kidney

- Glomeruli surrounded by visceral and parietal layer of Bowman's capsule

- P.T. --> descending limb --> ascending limb --> TAL --> distal tubule --> collecting ductule --> collecting duct

- Vascular tuft of capillaries --> Glomerular capillaries

- Endothelial cells, podocytes, and intraglomerular mesangial cells

- Vascular and urinary poles

- Urinary space

- Bowman's Capsule

- Outer spheroid layer of Bowman's Capsule

- Simple squamous

- Podocytes

- endothelial cells

- mesangial cells

- cell bodies and nuclei project into urinary space

- Pedicels and filtration slits --> form filtration barrier

- Negatively charged proteins

- Nephrin --> stops plasma protein passage

- Contractile properties --> alter blood flow

- Phagocytic --> maintain double basement membrane

- Extend between endothelial cells and podocytes

- Lacis Cells

- Resident fibroblast cells

- Vascular pole region

- Associated with macula densa and juxtaglomerular cells

- Cortical and medullary structures

- Cuboidal/pyramidal epithelial cells

- Acidophilic cells with microvilli and vacuoles

- Lots of basal mitochondria --> electrolyte and water reabsorption and basal enfoldings

- Squamous epithelium

- Nuclei bulge into lumen

- Relatively empty cytoplasm --> passive transport
- Medullary structure

- Cortical and Medullary

- Smaller cells with fewer microvilli and empty cytoplasm

- Basal enfoldings --> active transport of ions (Na, K, Cl)

- Macula Densa --> Afferent Arteriole

- Juxtaglomerular cells

- Extraglomerular Mesangial Cells

- Wall of distal tubule

- Samples distal fluid for NaCl content

- Interacts with juxtaglomerular cells

- Stimulates renin system

- Secrete renin --> PAS-staining renin granules

- Afferent Arteriole

- Intercalated Cells --> Dark staining (mitochondria)

- Principal Cells --> lighter staining

- Converge in Ducts of Bellini

- CT buffers between reabsorbed material

- Cortical Interstitial cells --> EPO release --> Increases RBCs

- Medullary Interstitial Cells --> Release prostaglandins

   - Pericytes present

- Ultrafiltrate --> Urinary Space (glomerular filtration)

- Filtrate --> After tubules (after reabsorption and secretion)

- Urine --> Collecting Ducts (with and without ADH)

- Urothelium (3 Layers)

- Basal Layer --> Stem cell population

- Umbrella Cell: Dome shaped, first line of defense against bacteria, assymetrical membrane (stretching)

- Intermediate Layer: Connected by desmosomes

- Transitional --> stratified squamous non-keratinized

- Internal Urinary Sphincter: smooth muscle

- Externa Urinary Sphincter: skeletal muscle

- Disruption of Urinary Sphincters

- Leads to inability to control passage of urine

- Keratinized

- No taste buds associated

- Mushroom shaped

- Two taste buds associated

- Large

- von Ebner's Glands empty into moats

- Numerous taste buds associated

- Purely serous

- Associated with circumvallate

- Ducts open into moats

- Largest major salivary gland

- Entirely serous

- Extensive duct system (striated and intercalated)

- Mostly serous (50/50) --> serous demilunes

- No striated or intercalated ducts just intralobular

- Short duct system

- Mostly serous (90/10)

- Much more extensive duct system, both straited and intercalated

- Secretory duct --> Pseudostratified epith. 

- Specialized parakeratinized epithelium around tooth

- Junctional epithelium --> attaches directly to enamel via hemidesmosomes

- 

- Shape dictated by shape of stellate reticulum

- Pulp cavity

- Odontoblast layer

- Dentin

- Cementum/Enamel

- Periodontal Ligament

- Bone

- Dental lamina --> ectodermally derived

- External enamel epithelium

- Stellate reticulum --> Desmosomes

- Internal enamel epithelium --> ameloblast layer

- Dental papilla --> Mesencymally derived, produces odontoblasts, cementum, and periodontal ligament

- 3,000 epithelial specializations

- Taste pore --> Apical opening

- Supporting epithelial cells

- Basal cells --> stem cell

- Associated with CN nerves

- Non-keratinized epithelium with Langerhans Cells

- Muscularis mucosae continuous in lower esophagus

- Esophageal glands --> submucosal (mucus)

- Musculiars externa (smooth/skeletal)

- Adventitia (top) and serosa (bottom)

- Mucosa --> gastric pits and cardiac/gastric glands

- Muscularis mucosae

- Thick muscularis externae (inner, middle, outer)

- Mucosa --> villi, plicae circularis, intestinal crypts, M-cells and Peyers Patches

- Musculiris mucosae --> inner circ and outer long.

- Submucosal glands

- inner circ and outer long. muscularis externae

- Enterocytes, goblet cells and paneth cells

- Similar to cardiac stomach glands

- Terminal portion of esophagus

- Produce mucus to protect against HCl

- Submucosal

- Upper esophagus

- Compound tubuloalveolar glands

- Mucus secreting

- Brunner's Glands (Branched tubular mucus secreting)

- M-cells and Diffuse GALT

- Peyer's Patches --> Orgainzed GALT

- Normal intestinal morphology (vili, etc)

- Exocrine cells at base of intestinal crypts

- Acidophilic apical granules

- Antibacterial lysozyme and zinc secretions

- cecum, colon, appendix, rectum, anal canal

- No enterocytes, just goblet cells

- Lots of lymphocytes

- Muscularis mucosae --> 2 layers

- Taeniae coli --> Muscularis Externa

- Lots of adipose tissue

- Diffuse patches of GALT

- No intestinal villi

- Intestinal crypts

- Ito cell

- Perisinusoidal space

- Contains fat and stores and releases vitamin A

- Basal surfaces --> sinusoids

- Apical surfaces --> bile canaliculi

- Lots of RER, mitochondria, SER, lysosomes, peroxisomes, and glycogen deposits

- Hepatocytes

- Ito cells

- Kuppfer cells

- Space of Disse --> Perisinusoidal

- Portal Lobule

- Hepatic Lobule

- Hepatic Acinus

- Exocrine and endocrine portions

- Islets of Langerhans

- Serous acini --> Zymogen granules

- Centroacinar cells

- Pancreatic Duct --> secretes pancreatic fluid

- No stratified ducts

- Uniform tall columnar epithelium --> Basal nuclei and short microvilli

- No muscularis mucosae

- Muscularis layer

- Adventitia and serosa --> Glisson's capsule

- Sphincter of Oddi 

- Conducting and Respiratory Zone

- Right lung (3 lobes) and left lung (2 lobes)

- Hilum (Doorway): Middle indentation of lunch surrounded by C.T.

- Carry deoxy blood away from right ventricle

- Travel and branch along with conducting airways

- End in pulmonary capillaries

- Travel in interlobular septae

- Carry oxy blood back to left atrium

- Under high pressure

- Natural right-left shunt

- Supply airways with blood supply

- Turbinates/conchae: 3 bony projections to create turbulence

- Ciliated pseudstratified epithelium

- Lamina propria: capillary rich

- Olfactory epithelium: olfactory cells, bipolar neurons, supporting and basal cells

- 16-20 c-shaped cartilage rings spanned by trachealis muscle

- Mucosa --> respiratory epithelium, BALT and MALT

   - ciliated, mucin secreting, and brush (sensory) cell

- Submucosa --> Elastic fibers

- Adventitia --> Cartilage layer

- No muscularis mucosae

- Most numerous cell type in epithelium

- Up to 250 cilia per cell

- Cilia beat particles up and out of trachea

- Apical microvilli

- Basal afferent neuron

- Sensory associated cell

- Extrapulmonary and intrapulmonary

- Intrapulmonary --> irregular shaped cartilage

- Complete circumferential muscle layer

- Lots of elastic fibers

- Submucosal glands

- <1 mm in diameter

- Pseudostratified to simple columnar/cuboidal

- Larger bronchioles --> mucous, ciliated, and Clara cells

- Smaller bronchioles --> Just Clara cells

- No cartilage or glands

- More elastic fibers than bronchi

- Bronchiole epithelium 

- Domed apical surface

- Principal stem cell

- Produce lipoprotein to keep airway patent

- Enzymatically detoxify noxious gases

- Muscularis layer contracts in asthma

- Few alveoli

- Both bronchiole and alveolar epithelium

- Opens into alveolar ducts

- Type I pneumocyte: 97% of surface area, very squamous, forms blood-air barrier

- Type II pneumocyte: Produce surfactant and stem cells

- Alveolar macrophage: becomes dust cell when in CT

- Pulmonary capillary --> Continuous endothelial

- Interalveolar Septum --> pulmonary interstitium

- Surfactant layer

- Type I pneumocyte

- Basal lamina

- Destruction of elastic fibers

- Secretion of elastase

- Reduction in alveoli --> loss of surface area

- Increases compliance of the lung and increase in FRC

- osteoblast: Secretes collagen for bone

- Fibroblast: Can produce ECM and CFU progenitors

- Endothelial Cell

- Mesenchymal stem cells --> Produce cytokines and help hematopoeisis

- Macrophage/monocyte --> secrete cytokine to encourage development

- Osteoclast --> reabsorb bone

- Red Marrow: Parenchymal

- Yellow Marrow: Adipocytes

- Blood supply: Thin walled plexus of sinusoids

- 3-4 weeks gestation: Yolk sac islands

- 5th week gestation: Liver

- Fetal spleen

- Yellow marrow start extending into middle shafts of long bones

- Age 10-14

- Age 25 --> Confined red marrow

- Capable to renew themselves

- Restricted in generating lineages

- "Colony Forming Units" (CFU)

- CMP --> CFU-GM, CFU-E, CFU-Meg, CFU-Eosin., CFU-B

- CLP --> CFU-LyT and CFU-LyB

- Multipotent OR committed

- Can only divide into a further differentiated cell

- Cannot renew itself

- ie promyelocyte or orthochromatophilic erythroblast

- BFU-E --> CFU-E, stimulated by EPO

- Proerythroblast --> basophilic erythroblast --> polychromatic erythroblast --> orthochromatophilic erythroblast --> reticulocyte --> erythrocyte

- 12-20 um diameter

- Large immature nucleus

- 3-5 pale nucleoli

- Blue stained cytoplasm

- ~15 um across

- characteristic cracked nucleus

- No nucleolus or granules

- Blue staining cytoplasm (ribosomes)

- Smaller than basophilic

- Coarsely clumped chromatin

- Eosinophilic Hb begins to contribute to coloring

- Blotchy looking cytoplasm

- Eosinophilic cytoplasm due to Hb

- Pyknotic nuclei

- Nucleus getting ready for extrusion

- Extruded nucleus

- Cytoplasm in different structure due to reticular fibers

- CMP --> CFU-GM, CFU-Eosin, CFU-Basophil

- Myeloblast --> promyelocyte --> myelocyte --> metamyelocyte --> band cell --> Mature

- Initial precursor cell

- 12-20 um diameter

- 3-5 prominent nucleoli

- No cytoplasmic granules

- Light blue cytoplasm

- Very large nucleus

- Large cells

- Lots of azurophilic granules

- One or more nucleoli

- Specific granules

- Pale golgi region

- Neutrophilic: Clear, pale Golgi area

- Eosinophilic: Orange-pink stained granules

- Basophilic: Purple staining granules

- Indented kidney shaped nucleus

- Marked nuclear indentation

- 85% specific granules

- 15% azurophilic granules

- Granulocyte leaves marrow at this stage

- Really only identified as neutrophilic

- Horse-shoe shaped nucleus --> starting to constrict

-Neutrophil: 3 or more lobes

- Eosinophil: 2 lobes and eosinophilic granules

- Megakaryoblast (25-40 um) --> Large lobed nucleus

   - Undergoes endomitosis

- Promegakaryocyte --> Polyploid cell

   - Huge cell (>100 um)

   - Post-endomitosis

- Platelet demarcation channels

- CLP --> CFU-LyT and CFU-LyB

- T-cells become immunocompetent in thymus

- B-cells become immunocompetent in bone marrow

- Monoblast: Round nucleus and nucleoli

- Promonocyte: Indented nucleus, less nucleoli and azurophilic granules present

- Precursors in marrow

- Monocytes in blood

- Reduction in ability to carry 02

1. Too few RBCs

2. Too many RBCs

3. Inadequat functioning RBCs

- Abnormality of WBCs

- Acute or chronic

- Lymphoid or myeloid

- Thymus and Bone Marrow

- Antigen-Independent Proliferation --> Immunocompetence

- Monitor thymocyte development

- Play role in immunological education

- Paracrine and endocrine

- Help in thymocyte differentiation and surface marker expression

- Endocrine --> circulate to peripheral lymph nodes

- Medulla

- Spheres of flattened epithelioreticular cells

- Thymocyte education

- Immature T-cells

- Migrate to outer cortex

- Migrate towards medullary sinuses as they develop

- Acquire MHC markers (CD4 or CD8 and TCRs)

- Positive and negative selection 

- Associated with mucosa

- Unencapsulated

- Organized or Diffuse

- M-cells and Langerhans cells

- Intraepithelial Lymphocytes --> reticulated epithelium

- Efferent lymphatics (HEVs)

- Unusually tall endothelial cells

- Allows diapedesis for lymphocytes into lymphatic vessels

- Selectins, integrins, and addressins

- Proliferation of B and T-cells

- Antigen-Dependent Proliferation

- Lymph nodes, MALT, and spleen

- Memory and effector cells produced here

- Cortex and Medulla

- Afferent and efferent lymphatics

- Reticular stroma (Type III) and reticular cells

- B-cells --> cortical nodules, germinal center (active)

- Paracortex --> T-cells

- HEVs in cortex --> Lymphocytes into node

- Filters for blood-borne pathogens (white pulp)

- Filters effete RBCs (splenic cords)

- White and Red Pulp

- Cords of Billroth and splenic sinuses

- Trabecular vessels --> surrounded by trabeculae

- Central arteries --> Through white pulp

- Radial artery --> Through marginal zone

- Penicillar Artery --> Into red pulp

- Splenic sinus vs cords (closed vs. open) 

- Cords --> reticular cells, fibers and macrophages

- Sinuses --> Line by stave cells (specialized endothelial)

- Blood flow from sinuses to pulp veins to travecular veins to splenic vein

- Contractile

- Can contract when blood flow is needed throughout the body and become very narrow

- Stellate Cells --> cytoreticulum

- Epithelioreticular Cells

  - Underly dense CT of capsule and septa

  - Encircle adventitia of vessels

  - Produce blood-thymic barrier

- Also contains nurse cells, hormone-secreting, and Hassall's corpuscles

- Reticular fibers and cells 

- Sinusoidal endothelial cells and macrophages

- Periosteum (Fibrous and cellular layer)

- Outer circumferential lamellae --> cementing lines

- Osteons and Haversian Canals

- Inner circumferential lamellae

- Endosteum --> lined by bone-lining cells

- Pale pink staining

- Pre-mineralized bone

- Secreted by osteoblasts

- Within scrotal sac

- Surrounded by tunica albuginea and tunica vascularis

- Mediastinum testis --> contains rete testis

- Germinal epithelium --> Sertoli cells and spermatogonia

- Leydig cells --> Stromal cells that produce testosterone

1. Spermatogonia

2. Primary Spermatocyte --> Meiosis I

3. Secondary Spermatocyte --> Meiosis II

4. Spermatid --> Undergoes morphological changes

   - Spermiated into lumen

- Sertoli cell processes surround spermatocytes to produce barrier

- Resident stem cells --> adjacent to basal lamina

- Produces about 1000-4000 spermatids

- Type A pale is induced by testosterone to become Type B spermatogonia

- Type B --> precursor cells

- Type A pale --> progenitor

- Type A dense --> reserve cells --> produce one type A dense and one type A pale

1) formation of acrosome

2) Acrosome elongation

3) Manchette forms

4) Flagellum forms

5) Packing of mitochondria

6) Intercellular bridges lost 

- Capacitation occurs in female

- Seminferous tubule leads into tubuli recti

- Gradual loss of germinal elements

- Only Sertoli Cells

- Simple cuboidal epithelial cells

- Rete Testis --> Network of anastamosing channels in mediastinum testis

- Upper pole of mediastinum

- Tall columnar ciliated cells --> simple columnar epith.

- Shorter absorptive cells

- Scalloped lumen appearance

- Creates fluid flow from rete testis towards epididymis

- 16 feet long

- Muscle layer

- Stereociliated pseudostratified epithelium

- Absorbs fluid

- 3 layers of muscle

- Pseudostratified epithelium

- Mucosa thrown into longitudinal folds

- Within spermatic cord

- Coiled, dilated portion of ductus deferens

- Storage of sperm

- Leads into ejaculatory duct of prostate

- Muscular coat

- Epithelium is thicker than ductus deferens and extensively folded

- No muscular coat

- Within prostate

- Prostatic and Penile portions

- Transitional to pseudostratified epithelium

- Glands of Littre in penile portion --> mucus goblet cells

- Outpouching of ductus deferens

- 2 layers of muscle --> inner circular and outer longitudinal layers

- Produces 80% of fluid

- Supplies fructose and prostaglandins to fluid

- Meshwork of thin trabeculae --> mucosal folds

- Non-ciliated pseudostratified epithelium

- ~ 25 branched tubuloalveolar glands

- Central, transitional, and peripheral zones

- Simple columnar epithelium with sparse basal cells

- Proteolytic enzymes secreted

- Expanded lumen --> follicles

- Interstitium is abundant (dense CT)

- Two pea-sized structures

- Clear viscous secretion

- Tubulalveolar mucus glands

- surrounded by muscle

- Corpus spongiosum --> surrounds penile urethra

- Pair of corpus cavernosa surrounded by tunica albuginea of penis --> contains helicine arteries

- Parasympathetic input

- Male hormones preserve Wolffian/mesonephric duct

- Female hormones stimulate paramesonephric duct

- Testis~ovary

- Attached to broad ligament by mesovarium

- Gametogenesis and steroidogenesis

- Germinal epithelium ontop of tunical albuginea of ovary

- Cortex --> ovarian follicles

- Medulla --> Loose CT and vessels/nerves

- Primary oocyte --> Primordial or primary follicles

  - Arrested at prophase I

- Secondary oocyte --> Secondary and Graafian follicles

  - Just prior to ovulation --> arrested at metaphase II

- Ovum --> zygote (occurs after fertilization)

- "Resting" stage

- Between 12-50 years 

- Found just beneath tunica albuginea of ovary

- Single layer of squamous cells surrounding oocyte

- Oocyte becomes active and enlarges

- Follicular cells become cuboidal --> Granulosa cells

- Zona pellucida: lines follicular cells and oocyte

  - Eosinophilic layer

- Theca Folliculi

- Stromal cells around follicle

- Theca Interna --> ovoid secretory cells (steroid)

- Theca Externa --> CT layer of smooth muscle and collagen

- Fluid-filled Antrum (Liquor folliculi)

- Cumulus oophorus --> thick portion of granulosa cells that projects into antrum

- Corona radiata --> Granulosa cells around oocyte

- Very large

- Just prior to ovulation --> Induced by LH surge

- Oocyte exits ovary via stigma of follicle

- Only one follicle is "selected"

- Sensitive to pituitary hormones

- Forms after ovulation

- Granulosa --> granulosa lutein

- Theca interna --> Theca lutein

- Secretes estrogen and progesterone

- Corpus luteum becomes corpus albicans

- Degenerating follicles

- Sloughing off of granulosa cells

- Pyknotic nuclei

- Basement membrane breaks down

- Infundibulum with fimbriae

- Ampulla

- Isthmus

- Intral portion/pars interstitialis

- Funnel-shaped structure

- Opens into peritoneal cavity

- Muscularis is relatively thick compared to mucosal folds

- Ciliated epithelium and peg cells

- Usually the site of fertilization

- Nourishes both oocyte and spermatid via peg cell secretion

- Movement changes from cilia to peristalsis

- Small lumen and thin mucosal folds

- Ovum movement by peristalsis via thick muscularis layer

- Body and Cervix

- Endometrium, myometrium, and perimetrium

- Uterine glands

- Simple columnar epithelium with ciliated cells and secretory cells

- Proliferative --> Estrogen spike from follice

- Ovulation --> LH spike from pituitary

- Secretory --> Progesterone from corpus luteum

- Menstrual --> Decline in estrogens and progesterone

   - Due to FSH from pituitary

- Endocervix --> simple columnar epith.

- Ectocervix --> stratified squamous non-keratinized

- Internal os and External os

- Plicae palmatae/cervical glands of endocervix

- Eversion of external os --> increased infections

- Much less muscle present --> type I and III collagen (80%)

- Softening --> Endocervical proliferation

- Ripening --> Increase in ground substance

- Dilation --> Influx of leukocytes

- Repair --> All stages reversed

- Stratified squamous non-keratinized epithelium

- No glands

- Mucosal rugae

- Glycogen stored in epithelial cells

- Produces lactic acid (pH 3)

- External genitalia

- majora ~ scrotum

- minora ~ penis

- Bartholin's and Paraurethral glands

- Simple squamous epithelium of blood vessels

- Modulate blood flow with local vasoconstrictors and vasodilators

- Regulate growth with the production of growth stimulators and growth inhibitors

- Folds of endocardium

- Enclose a platelike core of dense CT

- Anchored by papillary muscles and chordae tendineae

- Dense CT scaffolding 

- Four rings of dense CT (annuli fibrosae)

- Trigona fibrosa: Two triangular masses of CT

- Septum membranaceum: Dense fibrous plate in septum

- Specialized cardiac cells in walls of atria

- Peptides --> atriopeptin, ANP, cardiodilatin, and cardionatrin

- Largest arteries

- Maintain hydrostatic pressure

- Distinct elastic lamellae in tunica media

- Prominent internal and external elastic lamina

- Thick muscular tunica media

- One to three layers of smooth muscle in tunica media

- Main component of total peripheral resistance

- Semi-contractile

- Cellular processes that surround endothelial cells

- Involved in wound healing

- Very irregular in shape and caliber

- Supported by anchoring filaments (5-10 nm filaments) 

- Thin tunica intima and tunica media

- Thick tunica adventitia --> longitudinal smooth muscle

- Merocrine: Membrane-bound granule secretion

- Apocrine: Lipid-soluble secretion

- Holocrine: Secrete entire cell contents

- Papillary Layer: Knob-like papillae of CT that protrude into epidermis (Dermal papillae)

- Reticular Layer: Layer of coarse, densely interwoven collage fibers 

- Stratum Basale --> Stem cell layer

- Stratum Spinosum --> "Prickle" cell keratinocytes

- Stratum Granulosum --> Keratohyalin granules

- Stratum lucidum --> Flattened keratinocytes

- Stratum corneum --> Keratin layer

- Located in reticular dermis or hypodermis

- Deep pressure and vibration sensation

- Tips of dermal papillae

- Light touch sensation

- Nail plate --> non-nucleated corneocytes

- Proximal nail fold --> Continues as cuticle

- Eponychium --> undersurface of nail fold

- Hyponychium --> skin underlying distal nail

- Intermediate matrix --> Most of nail growth

- Ventral matrix/nail bed

- Specialized dendritic cells of the skin

- In stratum spinosum

- Produce melanin in melanosomes that protect against UV light

- Cytocrine secretion --> melanosomes surround nucleus of surrounding keratinocytes

- Special sensory cells

- Stratum basale

- Myelinated sensory fibers

- Sense of touch

- Unencapsulated sensory axons

- Penetrate epidermis and end in stratum granulosum

- Detect hot/cold, pain, pressure, and itch

- Simple coiled tubular

- Found in dermis

- Merocrine secretion

- Hair and follice

- Sebaceous Gland

- Arrector pili muscle

- Anagen: Active phase, 2-6 years (90% of growth)

- Catagen: Brief phase of reduced growth (3 weeks)

- Telogen: Resting phase (2-4 months)

- Abnormal hair loss

- Genetic sensitivity to androgens

- Localized increases of hair in women

- Andorgen-dependent areas

- Merocrine secretion

- Stimulated by sympathetic fibers

- Very large glands

- Thinned stratum corneum

- Transition between stratified squamous non-keratinized to stratified squamous keratinized

- No hair follicles associated

- Dental papilla

- Enamel organ --> Dental Follicle

- Stellate reticulum, outer and inner enamel epithelium

- Odontoblasts produce predentin

- Ameloblasts produce enamel against predentin

- Cementoblasts from inner cells of dental sac

- Short length glands

- Absence of parietal and chief cells

- Only mucous cells

- Mostly mucus-secreting cells

- A few parietal cells

- Produced by osteoblasts

- Stimulates the fusion of monocytes --> osteoclasts

- Pseudostratified ciliated epithelium

- Mucin secreting cells

- Thicker than respiratory epithelium

- Sensory

- Cell bodies of bipolar sensory receptors

- Sustentacular Cells: Non-sensory, supporting

- Basal cells --> stem cells

- Pseudostratified epithelium

1. Ciliated cells

2. Mucous Cells (~Goblet)

3. Small Granule Cells (~ECL cells in GI)

4. Brush Cell --> Sensory

5. Basal Cell --> stem cell

- Purely conducting

- Leads into respiratory bronchiole

- Only bronchiole epithelium present

- 97% of alveolar surface area

- Blood-air Barrier --> gas exchange

- Connected by tight junctions

- >.05 microns thick

- Stem cells

- Produce surfactant --> stored in multilammelar bodies

- Most numerous

- 5% of surface area

- Project into alveolar lumen

- Fibroblasts --> Elastic fibers and type III collagen

- Mast cells and macrophages

- Lymphatic vessels

- Indistinguishable in morphology from lymphocytes

- CMP (CFU-S or CFU-GEEM)

- CLP (CFU-Ly)

- Periarterial Macrophage Sheath (PALS)

- Close-packed sheath of macrophages

- Within red pulp

- Horizontal communication

- Outer plexiform layer

- Horizontal communication

- Inner plexiform layer

- Neuroglial cell of retina

- Throughout all 5 layers of retina

- Bowing of optic disc

- Increased intracranial pressure

- Perforations that penetrate sclera

- Optic disc axons travel through

- Cytoplasmic extensions of OPL neurons

- Present in fovea of retina

- Most numerous cells of collecting duct

- Aquaporins sensitive to ADH

- Cuboidal epithelial cells

- Involved in Acid-base Balance

- Less numerous cells

- Darker staining cytoplasm

- Epithelial layer of uterus

- Stratum functionalis --> lost during menstruation

- Stratum Basalis --> retained during menstruation

- Uterine glands

- Spiral arteries only extend into stratum functionalis

- Progressive elongation of the simple endometrial glands

- Proliferation of stromal cells in lamina propria

- Relatively straight glands

- Restores epithelium after menstruation

- Days 5-15 in cycle

- Endometrial glands become irregular in shape

- Days 16-28 in menstrual cycle

- Mitotic figures absent during late secretory phase

- Shedding of stratum functionalis

- Spiral arteries break down

- Days 1-5 of cycle

- Elevated area of modified highly pigmented epidermis

- Mammary/lactiferous ducts open into nipple

- Areola --> Modified pigmented epidermis surrounding nipple

- Consists primarily of duct system

- Alveolar tissue only really present when active

- Intralobular --> Interlobular --> lactiferous ducts --> lacteriferous sinus --> nipple/areola

- Ducts lined by simple cuboidal cells

- Alveolar cells look like ductal cells until pregnancy

- Once pregnancy occurs

- Under influence of estrogen

- Alveolar cells increase in size due to progesterone

- Colostrum produced due to progesterone

- Pre-milk substance

- High in protein

- Low in lipids

- High in antibodies

- RER, Golgi, and secretory vesicles in alveolar cells

- Under control of prolactin and oxytocin

- Stimulated by suckling and crying of baby

- Secreted by neurohypophysis

- Stimulates myoepithelial cells at base of alveoli

- "Letdown" reflex

- Secreted by adenohypophysis

- Stimulated by suckling and crying of baby

- Causes milk production

- Cervical mucus

- Capacitiation

- Corona radiata

- Zona pellucida

- Binding of sperm receptors --> Ca2+ mediated waves of activity

- Enzymes of acrosomal cap erode structures

- Penetration of oocyte by sperm completes meiosis II

- Produces ovum

- Sperm and ovum nuclei fuse --> zygote

- Cell mass divides about once a day

- 12-16 Cell stage

- Cells begin to differentiate

- Day 4 PF

- Day 6 PF

- Trophoblast layer --> placenta

- Inner cell mass --> fetus

   - ectoderm, mesoderm, and endoderm

- Developing fetus

- Enters uterus approximately 3 days PF

- Implantation Window (Days 21-25)

- Day 8/9 PF

- Cytotrophoblast layer --> Active inner cell layer

- Syncytiotrophoblast Layer --> Inactive outer layer

- Secretes Hormones

   1. Estrogens

   2. Progesterones

   3. human chorionic gonadotropin (hCG)

   4. lactogens

- Layer burrows into endometrial layer

- Endometrial stroma cells after implantation

- Undergo decidization

- Hormone-producing cells

- Forms by day 14 PF

- Encloses amniotic cavity

- Forms day 14 PF

- Outer membrane that faces decidua

- Formed by trophoblast layer combining with decidua

- Extends villi into decidua layer

- 10-12 weeks PF

- chorion and amnion fuse to form fetal membrane

- Vacuoles

- Spiral arteries breakdown and blood empties into lacunar spaces

- Eroded uterine glands also empty into lacunae

- Provide nutrients to fetus

- Day 11-13 PF

- Solid core of cytotrophoblast cells

- Covered with syncytiotrophoblasts

- Day 16 PF

- Loose core of mesoderm CT extends through center

- Day 22 PF

- Capillaries develop in CT core

- Capillaries grow from developing embryo

- Contain fibroblasts, smooth muscle cells, and macrophages

- Extend across villi

- Make direct contact with maternal decidua

- Anchor into decidual plate

- Do not connect directly to decidua

- Terminate in lacunae

- Main trunk villi

- Extends from chorionic plate into placental space

- "scout cells"

- Migrate away from the villous tree

- Fuse with the wall of maternal arteries/veins

- Take over function of smooth muscle

- Dilate maternal vessels

- Increase fetal blood supply

- Fibrous material found at sites where syncytiotrophoblast is disrupted

- Maintains blood-placenta barrier

- Similar to fibrin

- Produced when syncytiotrophoblast layer breaks down

- Higher in matrix components

- Lower in fibrous material

- Decidua graviditatis

- Decidua basalis --> beneath implantation

- Decidua capsularis --> covers the implantation site

- Decidua parietalis --> remainder of endometrium

- Placenta forms close to or overlying cervix

- Can deprive fetus of oxygen during delivery

- Hemorrhage of vessels can kill mother

- Tufts of fetal vessels surrounded the entrance of a maternal spiral artery

- Represents a cluster of fetal villi

1. Syncytiotrophoblast

2. Cytotrophoblast (when present)

3. Basal lamina of trophoblast

4. Basal lamina of endothelial cell

5. Endothelial cell of villus capillary

- Steroid Hormones --> Estrogen and progesterone

- Peptide Hormones --> hCG and hCS

- Prostaglandins --> Onset of labor

- Most common in ductal cells (80%)

- Genetic correlation

- Affects 1 in 8 women

- Anti-estrogen drug

- Common therapy for breast cancer

- Division of stem cells in stratum basale

- Mitotic spindle perpendicular --> cells remain in basale

- Mitotic spindle parallel --> Delamination

  - Daughter cell leaves stratum basale

- Canals that traverse a series of lamellae

- Travel perpendicular to Haversian Canals

- Formed by cells in the perichondrium

- Differentiate into osteoblasts

1. Zone of Resting Cartilage

2. Zone of Proliferation

3. Zone of Maturation and Hypertrophy

4. Zone of Calcifying Cartilage and Degenerating Chondrocytes

5. Zone of resoprtion and Ossification

- Phenylethanolamine N-Methyl Transferase

- Converts norepinephrine to epinephrine

- Adrenal Medulla Chromaffin Cells

- Central medullary vein

- Subcapsular arterial plexus

- Medullary Arteries --> runs straight through cortex to medulla

- Incorporation of Iodine into the tyros residues of thyroglobulin

- Thyroglobulin is produced by follicular epithelial cells

1. Rest on continuous basement membrane

2. Short microvilli

3. Joined to adjacent cells by junctional complexes

4. Extensive RER and golgi in cytoplasm

5. Colloid droplets when active 

6. Principal and secondary lysosomes

- Second cell type in parathyroid gland

- Do not secrete PTH

- Larger than principal cells

- Eosinophilic cytoplasm 

- Occur in large groups

- Appear in the gland around puberty

- Cells producing spermatozoa and testicular fluid

- Sertoli Cells and Spermatogenic Cells

- Entire process that begins with the primitive germ cell and continues through multiple stages and cell divisions and ends with the production of spermatids

- Takes about 64 days

- Supporting cells of the seminiferous epithelium --> contact the basement membrane and lumen

- Provide support, protection, nutrition, and developmental regulation

- Phagocytose excess spermatid cytoplasm

- Continuously secretes fluid

- Andorgen binding protein (ABP)--> testosterone

- Inhibin --> Inhibits FSH production

- Produce anti-Mullerian hormone during development

- Form blood-testis barrier

- Undergoes first meiotic division --> secondary

- Nucleus is clearly undergoing mitotic division

- Very short stage of development

- Undergoes Meiosis II division

- Haploid Cells

- Undergo spermiogenesis --> spermatozoa

- On opposite side of blood-testis barrier

- Corpora amylacea

- Ovoid, lamellar, and acidophilic

- Calcified glycoprotein and coagulated prostatic secretion

- Lamina propria of the urethra

- Mucous acinar glands

- Glycoprotein coat on spermatozoa 

- Secreted by ductus epididymis

- Capacitiation occurs in female reproductive tract

- Ductus deferens

- Pampiniform plexus--> venous

- Testicular artery

- Carries blood cooled in the periphery to the scrotum

- "precool"s the arterial blood traveling to the testis

- Central elevation of urethral mucosa

- Where the ejaculatory ducts enter into the prostatic urethra

- Vasodilator

- Produces NO that will cause dilation in the helicine arteries

- Increases blood flow to these arteries

- Causes erection

- Large, pale and spherical

- Transform from granulosa cells of the follicle

- Smaller and have less cytoplasm

- Transform from theca interna cells

- Formed in developing embryo

- Within primordial follicles

- Arrested at prophase I

- Just prior to ovulation meiosis I is completed

- Forms secondary oocyte and first polar body

- Arrested at metaphase II

- Ovoid secretory cells

- Inner, highly vascularized layer

- Secretes estrogen precursors

- Interstitial cells of the testis

- Produce testosterone

- Thickened portion of granulosa cells

- Project into antrum

- Stratum functionalis

- Stratum basalis

- Simple columnar epithelium with ciliated and secretory cells

- Contains uterine glands

- Spiral arteries --> stratum functionalis only

- Endometrial tissue present in peritoneal cavity

- Can lead to pain and ectopic pregnancies

- Treated with hormones and laser ablation

- Days 5-15

- Controlled  by estrogen secreted by ovarian follicles

- Growth of stratum functionalis

- Epithelial cells of the uterine glands reconstitute entire endometrial layer

- Day 16-28

- Controlled by progesterone from corpus luteum

- Only begins if ovulation has occurred (progesterone)

- Decidualization of endometrium upon implantation (About Day 23)

- Endometrial cells swell

- Produce cytokines in preparation for implantation

- Days 1-4

- Controlled  by the decline in estrogen and progesterone production by corpus luteum

- Spiral arteries begin to contract --> ischemia

- Surface epithelium is disrupted and blood vessels burst

- Portion of the adenohypophysis

- Wraps around the infudibulum

1. Neural tube outpouches and begins to form neurohypophysis and oral cavity evaginates to produce adenohypophysis

2. Neurohypophysis and adenohypophysis come into contact

3. Pars tuberalis wraps around infundibular stalk

- keratinized or parakeratinized

- Specialized for chewing

- Gingiva, hard palate and dorsal surface of tongue

- Non-keratinized epithelium

- Flexible --> adjusts to movement of underlying muscle

- cheeks, floor of mouth, ventral side of tongue, soft palate, and inner lip

- Mucosal membrane that reflects back over the alveolar bone 

- Extension of lining mucosa

- Adjacent to gingiva

- Leaf-like shape

- Lateral aspect of tongue

- Rudimentary in adult humans

- Functional in taste in children

- Decrease transparency of crystalline lens

- Due to exposure to UV light --> confromational change in crystallin structure

- Covers the entrance to the Canal of Schlemm

- Facilitates the flow of aqueous humour

- Phagocytic fibers

- Canal of Schlemm feeds into venous drainage of the eye

- Jelly-like substance

- Hyaluronic acid, proteoglycans

- Type II collagen and H20

1. Mucous from goblet cells

2. H20 from lactrimal glands

3. Lipid from tarsal glands --> prevent evaporation and creates a barrier between eyelids

1. Increase PO42- and Ca2+ concentration

2. Remove inhibitors of mineralization

3. Provide means to precipitate and bind mineral

4. Chondrocytes hypertrophy and produce matrix vesicles

5. Produce hydoxyapetitie crystals

6. Type X collagen produced to bind crystals

- Pale layer of osteoid that the osteoblasts rest upon

- Present in developing intramembranous bone

- Cartilage high in elastic fibers

- Present in the external ear

- Visualized using Verhoeff's stain

- Junction between the former anterior and posterior cells of the lens vesicle

- Posterior cells eventually elongate and lose their nuclei

- Mesonephros --> collecting tubule/duct and ureter

- Metanephros --> Loop of Henle

- Metanephric tissue around mesonephric tissue

   - Loop of Henle's around collecting ducts

- Secreted by Sertoli Cells

- Binds testosterone to concentrate it in the cells lining the testis

- Small outpouching of urethra

- Occurs at junction of ejaculatory duct and prostatic urethra

- 50% of men at 65 and 90% of men at 80

- Enlargment of the prostate

- Usually occuring in the central zone

- Leads to difficulty in urination

- Second most common type of cancer in men

- Most often in distal portion of the glands

- Associated with elevated levels of prostate-specific antigen (PSA) 

- PSA --> liquifies semen