Histology Lesson 3 PDF

HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 D. SUMMARY OUTLINE I. HISTOLOGY...

HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 D. SUMMARY OUTLINE I. HISTOLOGY VII. NERVOUS TISSUE A. TISSUES A. GENERAL INFORMATION B. FOUR BASIC TYPES OF TISSUES B. EXAMPLES II. CELL JUNCTIONS A. IMPORTANT TYPES OF CELL JUNCTIONS I. HISTOLOGY i. TIGHT JUNCTIONS Histo- = tissue; -logy = study. ii. ADHERENS JUNCTIONS The science that deals with the study of iii. DESMOSOMES tissues. iv. HEMIDESMOSOMES v. GAP JUNCTIONS A. TISSUES III. EPITHELIAL TISSUE Group of cells usually with the same origin in A. SURFACE EPITHELIUM an embryo and with the same function to i. SIMPLE SQUAMOUS carry out specialized activities. ii. SIMPLE CUBOIDAL iii. SIMPLE NONCILIATED COLUMNAR B. FOUR BASIC TYPES OF TISSUES iv. CILIATED SIMPLE COLUMNAR v. PSEUDOSTRATIFIED COLUMNAR 1. Epithelial vi. STRATIFIED SQUAMOUS Lines body surfaces and cavities, vii. STRATIFIED CUBOIDAL hollow organs, and ducts; also forms viii. STRATIFIED COLUMNAR glands. ix. TRANSITIONAL Allows the body to interact with both B. GLANDULAR EPITHELIUM its internal and external i. ENDOCRINE GLAND environments. ii. EXOCRINE GLAND 2. Connective IV. CONNECTIVE TISSUE Provides protection and support A. EMBRYONIC TISSUE Connective tissues bind organs i. MESENCHYME together, store energy reserves as fat, ii. MUCOID/MUCOUS and help provide the body with B. MATURE CONNECTIVE TISSUE immunity to disease-causing i. LOOSE CONNECTIVE TISSUE organisms. ii. DENSE CONNECTIVE TISSUE iii. CARTILAGE 3. Muscular iv. BONE TISSUE Specialized for contraction and v. LIQUID CONNECTIVE TISSUE generation of force. It generates heat that warms the V. MEMBRANES body. A. EPITHELIAL MEMBRANE i. MUCOUS MEMBRANE 4. Nervous ii. SEROUS MEMBRANE Generates electrical potential in iii. CUTANEOUS MEMBRANE response to stimuli which activates B. SYNOVIAL MEMBRANE muscle contractions and glandular secretions. VI. MUSCULAR TISSUE A. SKELETAL MUSCLE B. SMOOTH MUSCLE C. CARDIAC MUSCLE PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 1 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 ii. ADHERING JUNCTIONS Contains plaque and joined together by cadherins. ○ Plaque – a dense layer of protein on the inside of the plasma membrane attachment to microfilament. ○ Cadherins – transmembrane II. CELL JUNCTIONS glycoproteins. It crosses the The contact points between the plasma membrane and interacts with the membranes of tissue cells. proteins of other cells, forming the It is through cell junctions that cells interact junction. and how they are held with one another to Adhesion belts – extensive zones formed by form tissues. adhering junctions which encircle the cell. Helps epithelial surfaces resist separation A. FIVE MOST IMPORTANT TYPES OF CELL during various contractile activities (e.g. JUNCTIONS intestinal tissue). i. TIGHT JUNCTIONS Weblike strands of transmembrane proteins that fuse together the outer surfaces of adjacent plasma membranes to seal the passageway between cells. The transmembrane proteins prevent the contents of these organs from leaking into the blood of surrounding tissues. ○ Leak = through the gaps between the cells. Example: ○ Stomach lining ○ Intestinal lining ○ Urinary bladder lining ○ The walls of these organs do not allow any liquid to move out of that iii. DESMOSOMES space. Contain plaque and have cadherins which extend into the intercellular space between adjacent cell membranes and attach cells to one another. ○ Unlike in adhering junctions, plaque in desmosomes are attached to intermediate filaments, which consist of the protein keratin. The intermediate filaments extend to the cytosol, allowing desmosomes to contribute to the stability of the cells and tissue. Example: ○ Cardiac muscle (prevent heart from falling apart during contraction). ○ Epidermal cells (prevent skin from separating under tension). PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 2 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Plasma membranes are not fused together but are separated by a very narrow intercellular gap (space). Allows the cells in a tissue to communicate with one another ○ Particularly the conduct of chemical and electrical signals for regulation of cell growth and cell differentiation. Also allows the passage of ions, nutrients and wastes. ○ Through connexons, ions and small molecules can diffuse from the cytosol, but the passage of large molecules such as vital intracellular proteins are prevented. ○ Wastes generated by each cell are iv. HEMIDESMOSOMES moved through connections between other cells. Hemi = half; half desmosomes Resembles desmosomes but do not link adjacent cells. The transmembrane proteins are integrins instead of cadherins. ○ Inside plasma membrane: integrins attach to intermediate filaments made of the protein keratin. ○ Outside plasma membrane: integrins attach to the protein laminin present in the basement membrane. Anchors cell to basement membrane. III. EPITHELIAL TISSUE Epithelium aka epithelial tissue Arranged in continuous sheets Avascular (obtains nutrition via diffusion) Has nerve supply Closely packed cells held tightly together by many cell functions High rate of cell division (as part of boundary of organs Two types: ○ Surface epithelium - covering/lining v. GAP JUNCTIONS Outer cover of skin, some internal organs Connexins (individual membrane proteins) Inner lining of blood vessels, form connexons (fluid filled tunnels that ducts, body cavities connect neighboring cells). PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 3 of 17  HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Lining of respiratory, digestive, Reticular lamina urinary, and genital systems ○ Closer to the connective tissue; ○ Glandular epithelium contains collagen produced by Secreting portion of gland fibroblasts (connective tissue cells) Thyroid, adrenal, sweat, Purposes: digestive, glands ○ Migration surface for epithelial cells General functions: ○ Restrict passage of larger molecules ○ Protection, secretion, absorption, ○ Participate in filtration of the blood at excretion kidneys Various surfaces: ○ Anchor point for epithelial tissue ○ Apical - side facing body surface or luminal cavity A. SURFACE EPITHELIUM Lumen - hollow space within an organ Classifications: ○ Lateral - side facing adjacent cells; Number of layers contain cell junctions ○ Simple epithelium - single layer ○ Basal - opposite of apical; anchored to Function: osmosis, filtration, basement membrane via secretion, absorption hemidesmosomes Secretion - mucus, ○ Multilayered epithelia - apical is sweat, enzymes upper/outermost; basal is deepest Absorption - fluids and other substances (GI tract) ○ Pseudostratified epithelium - pseudo=false Looks like multiple layers, but actually only a single layer Respiratory epithelium - may have goblet cells (mucus secretion) and cilia ○ Stratified epithelium - 2 or more layers Shape of cells ○ Squamous - flat, allows passage of Basement membrane substances Thin extracellular layer composed of a basal ○ Cuboidal - as tall as they are wide, lamina and a reticular lamina (lamina = layer) may be shaped like cube or Found between epithelial and connective hexagonal; may have microvilli for tissue; connects them absorption or secretion Basal lamina ○ Columnar - taller than wide ○ Closer to and secreted by epithelial (rectangular); may also have microvilli cells; has laminin and collagen, ○ Transitional epithelium - changes glycoproteins, and proteoglycans shape from cuboidal and back ○ Laminin - attachment point of hemidesmosomes PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 4 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Allows distension (increase in ii. SIMPLE CUBOIDAL EPITHELIUM size); ex. urinary bladder epithelium One layer, square-shaped; as tall as it is wide Thin section of kidney tubules Also found in the eye, ovary, glands Function: ○ Secretion ○ Absorption Cross section of kidney tissue. The glomerulus is where the filtration of blood occurs. Millions i. SIMPLE SQUAMOUS EPITHELIUM of glomerulus are found in the kidney. The glomerulus has many ducts in which blood One layer, flat cells (Simple Squamous); may flows in. When blood flows in these ducts, look hexagonal at top view some substances are secreted and absorbed. Endothelium - Lines the cardiovascular and lymphatic systems Mesothelium - Lines the serous membranes of abdominal and thoracic cavities Found also in the air sacs of the lungs, the glomerular capsule of the kidneys, the inner surface of the cornea, and the tympanic membrane Usually not found in areas exposed to mechanical stress. Functions: ○ Filtration (kidneys) ○ Diffusion (lungs) - Diffusion in the lungs talks about the movement of gases across the membrane. The function of the lungs is to exchange carbon dioxide with oxygen. ○ Secretion (serous membranes) - Peritoneum is a serous membrane NOTE: Red blood cells have biconcave-shaped that lines the abdominal cavity cells. iii. SIMPLE NONCILIATED COLUMNAR EPITHELIUM Taller and wide For columnar epithelium, it is differentiated based on the presence of cilia. Lines digestive canal (stomach to anus), ducts of many glands, gallbladder Microvilli - Fingerlike projections that increase the surface area. If the surface area is increased, the tissue has more surface area for absorption and secretion, leading to increased absorption and secretion. It is important, especially for the GI Tract. Goblet Cells - Modified cells that secrete mucus ○ The function of mucus is for lubrication and protection from PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 5 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 stomach acid—Protective of the is the cilia that are found in the uterine tubes. epithelium. The cilia pushes the egg cell and is brought Functions: into the uterus. If the egg meets a sperm, ○ Secretion (columnar cells are more fertilization occurs. If not, the egg cell and the capable of secretion vs cuboidal cells) lining of the uterus would be expelled and ○ Absorption (increased absorptive area that is what we call menstruation. due to microvilli) In the respiratory tract, there is a mechanism to expel the particles you inhale and this is through your cilia. v. PSEUDOSTRATIFIED COLUMNAR EPITHELIUM iv. CILIATED SIMPLE COLUMNAR EPITHELIUM Can be ciliated or nonciliated Nonciliated Bronchioles of the respiratory tract, uterine ○ Epididymis, larger ducts of many tubes, uterus, paranasal sinuses, central canal glands, parts of the male urethra of spinal cord, ventricles of the brain ○ Function: Absorption and Secretion Cilia - hairlike projections that beat in unison to move mucus and foreign particles toward the throat Function: ○ Movement of mucus in the respiratory tract ○ Movement of oocytes in the uterine tubes (fallopian tubes) During ovulation, the ovaries release egg cells because of hormonal changes. It has to pass the uterine tubes for it to reach the site of Ciliated fertilization. The one that moves the egg cell PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 6 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 ○ The airway lining of most of the upper ○ Limited absorption and secretion respiratory tract ○ Function: Mucus secretion (goblet cells) and trapping and expelling foreign particles. viii. STRATIFIED COLUMNAR EPITHELIUM Urethra, anus, glands conjunctiva Functions ○ Protection ○ Secretion vi. STRATIFIED SQUAMOUS EPITHELIUM Epithelial tissue with 2 or more layers ○ Apical and upper layers are squamous ○ Cells in deeper layers are cuboidal to columnar Cells arise from the basal (deeper) layers and are pushed upward with cell division As they reach the upper layers, proteins accumulate, and the cells die, and may slough off as they reach the apical layer Locations ○ Keratinized: dry surfaces (skin) ○ Non-keratinized: wet surfaces (mouth, tongue, pharynx, esophagus, vagina) Function ix. TRANSITIONAL EPITHELIUM ○ Protection (abrasion, water loss, UV, Aka Urothelium foreign invasion) Stretched when filled (flattens) Urinary bladder, ureters, urethra Function ○ Allows stretching/distension without rupturing vii. STRATIFIED CUBOIDAL EPITHELIUM Male urethra, sweat and esophageal glands Function ○ Protection PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 7 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Functional Classification ○ Merocrine - secreted by vesicles ○ Apocrine - secreted by exocytosis B. GLANDULAR EPITHELIUM (“pinching off”) Function ○ Holocrine - secreted by cell rupture ○ Secretion Gland: Epithelium that secretes substances onto a surface, into ducts, or into the blood May be endocrine or exocrine ○ Endocrine Produce hormones (chemical messengers) Secretes to the bloodstream -> Systemic (widespread) effect ○ Exocrine Secretes into ducts that empty on an epithelium like the skin, the lumen of a hollow organ, etc More localized effect i. ENDOCRINE GLANDS Pituitary gland, pineal gland, thyroid and parathyroid glands, adrenal glands, pancreas, ovaries, testes, thymus Function ○ Regulation of several metabolic and physiologic processes by hormones ii. EXOCRINE GLANDS Unicellular vs Multicellular ○ Unicellular - Goblet cell IV. CONNECTIVE TISSUE Most abundant and most widely distributed PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 8 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Binds together, supports, strengthens, Link ground substance protects, insulates, transports components to each other and Energy reserve and immune function to cells 2 basic elements: extracellular matrix (ECM) Fibronectin: binds to collagen and cells and to ground substance ○ ECM (secreted by cells): protein fibers ○ Question: If glucosamine and + ground substance chondroitin are joint components, Ground substance wouldn’t supplements be useful in Fluid, semifluid, osteoarthritis? gelatinous, or calcified They don’t provide relief for Function: supports cell, those with osteoarthritis. binds cells together, Supplements don’t work stores water, provides Supplements can be medium for exchange dangerous of substances between Supplements are a waste of blood and cells money Extracellular fiber Connective Tissue Fibers Secreted by cells, ○ Protein fibers impart functional Strengthen and support tissue properties of the tissue ○ Collagen The fiber is the protein Very strong and resist pulling, Connective Tissue Cells (cells derive from but not stiff mesenchymal origin) Properties depend on ○ Fibroblasts: large and flat, has surrounding molecules (e.g. branching processes, most numerous, cartilage v bone) and present in all general connective Bundle arrangement for tissue greater tensile strength ○ Macrophages: phagocytes (eating ○ Elastic cells) Elastin + fibrillin (glycoprotein) ○ Plasmocytes: plasma cells Stretchable (up to 1.5x original ○ Mast Cells: inflammation length) and able to return to ○ Adipocytes: fat cells original shape (elasticity) ○ Leukocytes: WBC ○ Reticular Connective Tissue Ground Substance Bundled collagen coated with ○ Glycosaminoglycans (Polysaccharides) glycoprotein - it is not only a carbohydrate or sugar Reticular = netlike since glycosaminoglycans also have a Also for support and strength protein component Areolar connective tissue; Hyaluronic acid: lubricates adipose tissue nerve fibers, joints, maintains eyeball shape, smooth muscle tissue binds cells together, and Connective Tissue Classification broken down by hyaluronidase from WBCs and bacteria Embryonic Mature Mature Chondroitin sulfate: support and adhesiveness in cartilage, -Mesenchyme -Connective tissue -Supporting bone, skin, and blood vessels -Mucoid/muco proper connective tissue Dermatan sulfate: skin, us connective Loose Cartilage tendon, blood vessels, heart tissue connective ○ Hyaline tissue cartilage valves ○ Areolar ○ Fibrous Keratan sulfate: bone, connective cartilage cartilage, cornea tissue ○ Elastic ○ Adhesion proteins PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 9 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 ○ Adipose cartilage ○ Description: Composed of adipocytes tissue Bone tissue (from fibroblasts) ○ Reticular ○ Compact White adipose (large connective bone triglyceride droplet) and brown tissue ○ Spongy adipose (many blood vessels Dense bone and mitochondria) connective Liquid tissue connective ○ Location: Wherever areolar ○ Dense tissue connective tissue is located: regular ○ Blood subcutaneous layer deep to skin, connective ○ Lymph around heart and kidneys, yellow bone tissue plasma marrow, padding around joints and ○ Dense behind eyeball in eye socket irregular connective ○ Function: Thermoregulation tissue (especially in brown adipose), energy ○ Elastic source, protection. Brown adipose is connective abundant in infants as protective tissue mechanism. It helps in producing heat. A. EMBRYONIC TISSUE Found in developing embryos/fetuses i. MESENCHYME Embryo (first two months of development) Function: gives rise to all other tissues Loose Connective tissue - Areolar ○ Description: Packing material, most widely distributed ○ Location: In and around nearly every body structure (thus, called “packing material” of the body): in subcutaneous layer deep to skin; papillary (superficial) region of dermis of skin; lamina propria of mucous ii. MUCOID/MUCOUS membranes; around blood vessels, Fetus (third month and beyond) nerves, and body organs Found in the umbilical cord ○ Function: strength, elasticity, support Function: support Loose Connective tissue - Reticular ○ Description: Reticular fibers + reticular B. MATURE CONNECTIVE TISSUE cells i. LOOSE CONNECTIVE TISSUE ○ Location: Stroma (supporting framework) of liver, spleen, lymph Loose Connective tissue - Adipose nodes; red bone marrow; reticular PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 10 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 lamina of basement membrane; perichondrium of cartilage; around blood vessels and muscles articular capsule in joints; ○ Function: Forms stroma (supporting capsule of other organs. framework) for many organs, binds iii. Function: Offers tensile smooth muscle, filters, removes strength in parts where pulling worn-out blood cells in spleen + is exerted in various microbes in lymph nodes directions. Cannot withstand as much force as Dense Regular CT. ii. DENSE CONNECTIVE TISSUE Contains more numerous, thicker, and denser c. Elastic Connective Tissue fibers (packed more closely) but considerably i. Description: Consists fewer cells than loose connective tissue. predominantly of freely Types: branching elastic fibers; a. Dense Regular Connective Tissue fibroblasts are present in i. Description: Regularly spaces between fibers. arranged collagen fibers along ii. Location: In elastic arteries, a single axis. trachea, bronchial tubes, true ii. Location: Forms tendons vocal cords, ligaments (muscle to bone), ligaments between vertebrae, (bone to bone), and suspensory ligaments of penis. aponeuroses (sheetlike iii. Function: For organ elasticity. tendons for Allows stretching and muscle-muscle/muscle-bone recoiling. attachment). iii. Function: Strong attachment (can withstand pulling tension along axis). iii. CARTILAGE Consists of a dense network of collagen fibers and elastic fibers firmly embedded in chondroitin sulfate. b. Dense Irregular Connective Tissue Strength: due to dense network of collagen i. Description: Irregularly and elastic fibers. arranged collagen fibers and a Resilience: due to the chondroitin sulfate; few fibroblasts Resistance to tension, compression, and ii. Location: Fascia (covering) of shear. muscles and organs; fibrous Anti-angiogenesis factor: No nerves or blood pericardium (“peri-” = vessels covering) of the heart; Covered by dense irregular CT layer called periosteum of bone; perichondrium (has nerves & blood vessels). PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 11 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Chondrocytes - cells of a mature cartilage; i. Description: Chondrocytes occur within spaces called lacunae. scattered in networks of elastic In fetuses, cartilages form first, which later fibers. develop into bones. ii. Location: Epiglottis, auricle Types: (ear), auditory tubes. a. Hyaline Cartilage iii. Function: Strength and i. Description: “Glassy” due to a elasticity; maintains shape of bluish-white, shiny appearance; structures. collagen not visible; most abundant cartilage type. ii. Location: Found at ends of long bones, anterior ends of ribs, nose, larynx, trachea, bronchi, and embryonic & fetal skeleton. iii. Function: Smooth joint movement, flexibility, and iv. BONE TISSUE support. Skeletal system = cartilage, joints, bones Bones are organs Functions: ○ Support soft tissue and for protection ○ Voluntary movement ○ Homeostasis of calcium (99% stored in bones) and phosphate ○ Erythropoiesis (RBC and other blood components production ) in red marrow b. Fibrocartilage ○ Triglyceride storage in yellow marrow i. Description: Visible thick Types: bundles of collagen; no a. Compact bone perichondrium; strongest i. Its basic unit, osteon, has 4 type. parts: ii. Location: Pubic symphysis 1. Lamellae - concentric (hip bones), intervertebral rings of calcium and discs (spine), knee menisci, phosphate ECM. parts of tendon inserting into 2. Lacunae - spaces cartilage. containing osteocytes iii. Function: Support and joining (mature bone cells). structures. 3. Canaliculi - projections from lacunae allowing nutrient inflow and waste outflow of osteocytes. 4. Osteonic canal - contains blood vessels and nerves. c. Elastic Cartilage PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 12 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Flat sheets of pliable tissue that cover or line a part of the body. Types: Epithelial and Synovial membranes A. EPITHELIAL MEMBRANE Combination of an epithelial layer and an underlying connective tissue layer Types: a. Mucous membrane b. Serous membrane b. Spongy bone c. Cutaneous membrane/Skin i. Also called cancellous bone ii. Inside the compact bone i. MUCOUS MEMBRANE iii. Lacks osteons iv. Consists of thin columns called bone trabeculae (also contains lamellae, osteocytes, lacunae, and canaliculi). v. Spaces filled with red marrow (gives rise to different blood components) Also called mucosa Description ○ Lines a body cavity that opens directly to the exterior Location ○ Digestive, respiratory, reproductive, and urinary tracts Epithelial layer ○ Goblet cells secrete mucus which prevents cavities from drying out, traps particles in the respiratory tract, v. LIQUID CONNECTIVE TISSUE and lubricates food in the GI tract. a. Blood tissue ○ Site of food and fluid absorption. i. Components: ○ Epithelia vary in different parts of the 1. Plasma - pale yellow fluid + body. dissolved substances Connective tissue layer 2. Formed elements ○ Areolar CT (erythrocytes or RBC, ○ Called the lamina propria leukocytes or WBC, ○ Supports the epithelium, binds it to thrombocytes or platelets) the underlying structures, and allows ii. Function: O2 and nutrient delivery, flexibility. and immune functions (WBC) ○ Holds blood vessels b. Lymph ○ Oxygen and nutrients diffuse from i. Liquid connective tissue in lymphatic lamina propria to the epithelium vessels ii. Much less protein vs. blood ii. SEROUS MEMBRANE iii. Composition depends on location V. MEMBRANES PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 13 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 ○ Keratinized stratified squamous ○ Protects underlying tissues CT layer ○ Found in the dermis ○ Areolar and dense irregular CT B. SYNOVIAL MEMBRANE Also called serosa Lines a body cavity that does not open directly to the exterior, and it covers the organs that lie within the cavity. Epithelial layer ○ Mesothelium (simple squamous) ○ Secretes serous fluid, allowing organs to glide over one another or against walls of cavities. Lines joints and contains connective tissue Serous membrane of the but no epithelium. thoracic cavity and lungs: Composed of a discontinuous layer of cells pleura called synoviocytes Serous membrane of the heart: ○ Closer to the synovial cavity (space pericardium between the bones) and a layer of Serous membrane of connective tissue deep to the abdominal cavity and organs: synoviocytes peritoneum ○ Secretes synovial fluid - lubricates CT layer and nourishes cartilage and contains ○ Areolar CT macrophages that remove microbes Serous membranes have two layers: and debris. ○ Parietal layer Attached to and lining the VI. MUSCULAR TISSUE cavity wall Composed of elongated cells called muscle ○ Visceral layer fibers or myocytes Covers and adheres to the ○ This uses ATP to generate force organs within the cavity ○ Has multiple mitochondria to supply more energy iii. CUTANEOUS MEMBRANE ○ Formed through myogenesis Common functions ○ Body movement ○ Body posture maintenance ○ Heat production ○ Protection A. SKELETAL MUSCLE These are voluntary muscles for voluntary movement. Also called the skin Physical characteristics Covers the entire body and consists of ○ Are long cylindrical fibers with epidermis and dermis striations (striped) Epithelial layer ○ Up to 30 to 40 cm long in the longest ○ Found in the epidermis muscles PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 14 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 Location ○ Contains actin and myosin which are ○ Can be found around the body the main proteins for muscle between bones contraction ○ This is attached to bones through the tendon Function ○ Aid for voluntary movement ○ Body posture ○ Heat production ○ Protection Example of combined smooth muscle and skeletal muscle function ○ Rectum: final storage of the feces before it is expelled ○ The rectum has two sphincters: internal and external The external anal sphincter is a striated or skeletal muscle Responsible for B. SMOOTH MUSCLE holding in feces once internal anal sphincter These are involuntary muscles cannot contain pressure Physical characteristics (voluntary movement) ○ Non-striation The internal anal sphincter is ○ Source of it being called ‘smooth’ a smooth muscle muscles is that it does not have Will hold until pressure striations can be withstood by the ○ Small spindle-shaped cells muscle (moves Location involuntarily) ○ Iris of the eyes ○ Blood vessel walls ○ GI Tract ○ Airways ○ Gallbladder ○ Urinary bladder ○ Uterus Function ○ Aid for involuntary movement PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 15 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 C. CARDIAC MUSCLE VII. NERVOUS TISSUE These are involuntary muscles. A. GENERAL INFORMATION Physical characteristics ○ Has striations but less visible than Cells are called neurons skeletal muscles Parts of the neuron ○ Contains intercalations ○ Cell body ○ Visible: intercalated discs Spherical part of the cell For plasma membrane Contains nucleus and other thickenings organelles Has desmosomes: holds cells Controls all the functions of together during vigorous the cell contractions Connects nucleus to the Has gap junctions: for dendrites and the axon conductivity ○ Dendrite ○ Is unique due to its branching Finger-shaped cells present at Location the end of the neuron ○ This comprises the thick layer of the These are projections of the heart cell body ○ It is surrounded by a thin layer of Increase surface area to epicardium and inner endocardium receive the input or Function information ○ Aid for involuntary movement of the Receives information from heart other neurons (presynaptic ○ Responsible for blood pumping neurons) or from the ○ Muscle for the contraction of the environment heart during pumping ○ Axon Long, tail-like projections Connects to the cell body through the hillock and contains myelin which helps the axon’s function Conducts impulses used for communication from the brain to the rest of the body D. SUMMARY Location ○ Found in the brain, spine, and in the nerves ○ Neurons are found all over the body due to the importance of their function Function PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 16 of 17 HISTOLOGY PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) James Louie D. Tronco, RPh, MD | HYNITH: BSP 2023 | YEAR 2 SEM 1 | AY 2024-2025 ○ Converts stimuli to action potentials to cause the different parts of the body to move Example Sounds cause vibrations which are contained to be able to hear these sounds ○ Conduction of action potentials to different parts of the body ○ We are individualized because nerve cells are connected in different ways. B. EXAMPLES Hippocampal cells ○ In hippocampus: responsible for memories ○ Receives excitatory contacts ○ Path: stimuli to nerve impulse to impulse conduction to target organ ○ Use of special function to make functional parts light up Satellite glial cells ○ From dorsal root ganglia (DRG) ○ Another accessory cell in the nervous system ○ Covers the cell bodies in ganglia of the peripheral nervous system PHARM 120 (HUMAN ANATOMY AND PHYSIOLOGY FOR PHARMACY 1) Bolos, De Guzman, Felipe, Pongo, Samson, Santos, Valencia Page 17 of 17