What organelle is involved in drug detoxification and release and recapture of calcium ion during contraction and relaxation of muscles?
Smooth ER
What can be stained with silver salt or osmium and appears as a black network of cisternae?
Golgi complex
What are the functions of the golgi complex?
Provides site for the accumulation, concentration and packaging of secretory proteins into membrane bound vesicles.
Biosynthesis of glycoproteins, glycolipids, phospholipids, and neutral lipids.
How are lysosomes made?
Lysosomal enzymes are synthesized in the rER and transferred to the golgi complex where the enzymes are modified and packaged as primary lysosomes.
What are lysosomes?
Membrane-bound vesicles that contain various hydrolytic enzymes e.g. nucleases, proteases, lipases, etc.
What is a secondary lysosome?
When a primary lysosome fuses with the phagocytosed material or obsolete cellular organelles.
After digestion, the contents of the secondary lysosomes are retained as ______.
Residual bodies or lipofuscin (age pigment).
What is used to show the relative age of cells?
The amount of lipofuscin in the cell.
Describe and list functions of peroxisomes.
Small membrane-bound organelles, containing oxidase and catalase enzymes
Synthesize and destroy hydrogen peroxide; Detoxify certain substances and play a role in gluconeogenesis.
What is the significance of peroxisomes?
The energy dervied from oxidation is used for metabolic processes.
Where are peroxisomes found abundantly?
Hepatocytes
Cells of the proximal convoluted tubules of the kidney.
What is Janus Green B stain used for?
Mitochondria
What is the function of mitochondria?
The chief source of energy for the cell.
What does the inner membrane of the mitochondria contain?
Enzymes that function in oxidative phosphorylation.
What is the cytoskeleton composed of?
Microfilaments
Intermediate filaments
Microtubules
What is the composition of microfilaments?
Actin and myosin filaments, which cause cellular contraction in muscle cells.
In which type of cellular activities are microfilaments involved?
Endocytosis
Exocytosis
Cell migratory activity
In which types of cells are intermediate filaments abundant?
Cells subject to mechanical stress.
What is the function of keratin filaments?
Mechanical stability by formation of desmosomes
Protection in keratinized epithelium
Which filaments support muscle cells?
Desmin filaments
Which filaments support nerve cells?
Neurofilaments
Which filaments support astrocytes and neurolemmocytes (Schwann cells)?
Glial filaments
What are the functions of microtubules?
Maintenance of cell form
Transport of organelles and vesicles, such as secretory granules
What is the makeup of the centriole.
Nine groups of three microtubules (triplets) in longitudinal and parallel arrangement.
What are the cytoplasmic inclusions?
Glycogen
Lipid
Melanin
Hemosiderin
Lipofuscin
Which inclusion is in liver cells and muscle and how can it be demonstrated?
Glycogen
Demonstrated by PAS reaction.
Where is lipid and how can it be demonstrated?
In adipose cells, can be demonstrated with osmic acid fixation.
What inclusion is in skin and pigment epithelium of retina?
Melanin.
What is hemosiderin?
Result of hemoglobin degradation
What is indigestible residue of phagocytosis, which increases with age?
Lipofuscin
In which cells are lipofuscin commonly found?
Cardiac muscle, liver and nerve cells.
Where are tight junctions found and what do they consist of?
Epithelial cells
Consist of irregularly anastamosing ridges (transmembrane protein) that seal neighboring cells together in a beltlike fashion.
What are the three types of adhering junctions?
Zonula adherens
Macula adherens or desmosomes
Hemidesmosomes
What cell junction holds cells together by transmembrane protein linker and a bundle of actin filaments run parallel to the junctional cell membrane? In what cells are they prominent?
Zonula adherens
Lining cells of the intestine
What is the structure of a desmosome or macula adherens?
Transmembrane protein linker plus intercellular electron-dense plaque. Intermediate filaments are attached to this plaque forming a hairpin loop.
What connects cells to extracellular matrix protein?
Hemidesmosome
What permits the direct passage of inorganic ions and other water-soluble molecules from cell to cell?
Gap junction
What do gap junctions do?
Connects the intercellular space by interlocking transmembrane proteins of the opposite membrane.
What is cilia composed of?
Nine doublet microtubules around two central microtubules.
What is a flagellum?
A single long cilium.
What are microvilli?
Cytoplasmic evaginations to increase the free surface for absorption (e.g. small intestine)
What are stereocilia?
Long, rigid microvilli e.g., hair cells of the spiral organ (corti) of the inner ear.
What does the basement membrane consist of?
Basal Lamina - Lamina lucida and lamina densa
Subbasal lamina or reticular lamina
What layer of the basement membrane is composed mainly of proteoglycans and a special type of collagen?
Basal lamina
What is the subbasal lamina composed of and what is its function?
Reticular fibers
Connects the lamina densa to the subepithelial connective tissue
What are the functions of the epithelium?
Protection, absorption, secretion and diffusion
What are the two ways to classify epithelium?
Number of layers present (simple or stratified)
Shape of the top layer of cells (i.e. squamous, cuboidal, columnar)
Where can you find simple squamous epithelium?
Lining of the blood vessels
Pleural and peritoneal cavities
Pulmonary alveoli
Glomerular capsule
Where can you find simple cuboidal epithelium?
Thyroid gland
Collecting ducts of the kidney
Where can you find simple solumnar epithelium?
Stomach
Intestine
Gall bladder
What is pseudostratified columnar epithelium and where is it found?
Single layer of cells, but because of the different cell shape and nuclei location at various levels, gives an impression of stratified epithelium.
Trachea and bronchi (ciliated form)
What is the difference between keratinized and non-keratinized cells?
Keratinized cells have layers of dead cells on top of the epithelium for protection.
Where can you find stratified squamous epithelium?
Skin (keratinized) and cornea (non-keratinized)
Where can you find stratified cuboidal epithelium?
Lining the excretory duct of glands
Where can you find stratified columnar epithelium?
In parotid and mandibular gland ducts
Which type of cells line certain hollow organs and is capable of considerable distention and give examples?
Transitional epithelium, e.g. urinary bladder and urethra.
What part of the gland consists of secretory epithelium and duct system?
Parenchyma
Which part of a gland is the supportive framework of connective tissue?
Stroma
What are the different classifications of glands?
Unicellular (goblet cells) or multicellular
Endocrine or exocrine
Simple or compound
What is the difference between endocrine and exocrine glands?
Exocrine - has a system of ducts
Endocrine - ductless, secretions released into intercellular fluid and transported by blood
Give an example of each gland:
Simple straight tubular
Large intestine
Give an example of each gland:
Simple coiled tubular
Sweat gland
Give an example of each gland:
Simple branched tubular
Stomach
Give an example of each gland:
Simple alveolar or acinar gland
Sebaceous gland
Give an example of each gland:
Simple branched acinar or alveolar gland
Large sebaceous gland
Give an example of each gland:
Simple tubulo-acinar gland
Minor salivary gland of oral cavity
Give an example of each gland:
Compound alveolar or acinar
Parotid gland
Give an example of each gland:
Compound tubulo-alveolar
Pancreas
What is the order of the duct system from smallest to largest?
Intercalated ducts
Intralobular
Interlobular
Lobar ducts
Main ducts
Which glands produce a thin, watery secretion and have spherical nuclei in the center or lower half of the cell?
Serous glands (e.g. Parotid salivary gland)
Which glands procude a thick, viscous secretion with flattened nuclei displace to the basal part of the cell?
Mucous glands
What is a seromucous gland?
Has both serous and mucous glands. Generally, serous cells are located over the mucous acini as serous demilunes (e.g. in the mandibular salivary gland)
What is merocrine secretion?
Secretory granules enclosed in a membrane, discharged by exocytosis.
What is apocrine secretion?
Membrane-bound granule, together with a rim of cytoplasm and plasmalemma, is released from the apex of the cell e.g., sweat and mammory glands
What is holocrine secretion?
Entire cell is released as the secretory product e.g., sebaceous glands
What is cytocrine secretion?
The secretory material from one cell is transferred to the cytoplasm of another cell, e.g., transfer of melanin pigment from the melanocytes into the keratinocytes.
What forces the secretory product into the duct system and where is it located?
Myoepithelial cells
Interposed between the secretory cells and basement membrane
Which cells can differentiate into other cells?
Mesenchymal cells
Pericytes
Which cells are responsible for the synthesis of fibers and intercellular ground substance?
Fibroblast cells
What is an inactive fibroblast?
Fibrocyte
What type of fibroblast contains actin filament and plays a role in contraction during wound healing?
Myofibroblast
What cells are stellate-shaped with spherical nucleus and basophilic cytoplasm, and produce reticular fibers?
Reticular cells
Which cells are fillied with large lipid droplets and nucleus is displaced to the periphery?
Unilocular adipocytes
Which cells have a centrally located nucleus with multiple lipid droplets and high concentration of mitochondria in the cytoplasm?
Multilocular adipocytes
What are pericytes?
Cells located adjacent to the endothelium lining small blood vessels
Contain actin and myosin
Have potential to transform into other cells
Participate in healing process
What cells turn red when stained with toluidine blue?
What cells are spherical or ovoid with spherical, eccentric nucleus and the arrangement of chromatin gives the nucleus a cart-wheel-like appearance and are intensely basophilic?
Plasma cells
What do plasma cells develop from and what do they produce?
They develop from B-lymphocytes
Produce antibodies (plasma cells are abundant in lymphatic tissues and lamina propria of the GIT)
What do monocytes turn into when they migrate across the blood vessel walls into the connective tissue?
Macrophage
What do macrophages contain?
Cytoplasmic vacuoles and numerous lysosomes.
What are the three types of fibers and their descriptions?
Collagen - wavy
Reticular - networks
Elastic - Coiled
Where are collagen fibers found?
Tendon
Ligament
Organ capsule
Which fibers are strong and flexible and inelastic?
Collagen fibers (tendon, ligament, organ capsule)
Which fibers are stained red with Van Gieson's method?
Collagen fibers
What fibers can be stained with silver impregnation (argyrophilic or argentaffin fibers) or PAS agent?
Reticular fibers
Where are reticular fibers?
They form the framework of liver, endocrine, lymphatic organs.
What is the makeup of reticular fibers?
Individual collagen fibrils (type 3 collagen) coated with proteoglycans and glycoproteins.
What is used to stain elastic fibers?
H&E (stains light pink)
Stained selectively by orcein and resorcin-fuchsin
Where are elastic fibers found?
Present in structures that require elasticity e.g., aorta and muscular arteries, nuchal ligament, pinna of ear and lungs.
What is an amporphous ground substance composed of?
Glycosaminoglycans (GAGs) and proteoglycans
What are the major types of GAGs and where are they found?
Hyaluronic acid - vitreous body of eye and in synovial fluid
Chondroitin sulphate - cartilage, bone and large blood vessels
Dermatin sulphate - tendons and ligaments
Keratin sulphate - cartilage and bones
Heparin sulphate - arteries and lungs
What are the types of Embryonic CT?
Mesenchymal CT
Mucous or gelatinous CT
What are the types of adult CT and where are they found?
Loose or Areolar CT; beneath the epithelium, around blood vessels and nerves, and in serous membranes
Dense CT; Irregular - in capsules of the organs, deep layer of the dermis; Regular - tendons, ligaments and aponeurosis
Elastic CT; Nuchal ligament, vocal ligament
Reticular CT; Spleen, lymph node and liver
Adipose CT; loose CT of mesenteries, around blood vessels and nerves
What does cartilage consist of and lack?
Consists of cartilage cells (chondroblasts and chondrocytes) and matrix
Lacks blood vessels
Label the parts:
A : Perichondrial fibroblast
B : Chondroblast
C : Interterritorial matrix
D : Chondrocyte
E : Territorial matrix
Unilocular adipocyte
Label this cell:
Hyaline cartilage
Find these parts:
Chondrocyte
Territorial matrix
Interterritorial matrix
Label the cartilage:
Elastic cartilage
Label these parts:
Chondrocyte
Elastic fibers
Label the picture:
Fibrocartilage
Label these parts:
Collagen fibers
Chondrocyte
(No perichondrium)
What is cartilage matrix composed of?
Fibers and ground substance containing proteoglycans and GAGs (chondroitin sulphate, keratin sulphate, hyaluronic acid) and the adhesive molecules (chondronectin and fibronectin).
What are the 3 types of cartilage and where are they found?
Hyaline - articular surfaces of bones, nose and trachea
Elastic - pinna and epiglottis
Fibrocartilage - intervertebral discs and menisci
Bone is a specialized connective tissue composed of what?
Intercellular calcified material (bone matrix)
Three cell types (Osteoblasts, osteocytes, osteoclasts)
What do osteoblasts secrete?
Osteoid (organic matter of bony matrix) which is subsequently calcified by the deposition of calcium salts.
What cell makes new bone?
Osteoblast
What cell functions in bone resorption and how?
Osteoclast
Secretes acid and lysosomal enzymes
A - Osteoblast
B - Osteoclast
C - Osteocyte
D - Mesenchyme
E - Bone matrix
F - Newly forming matrix (osteoid)
Label the parts:
A - Inner circumferential lamellae
B - Haversion system (osteon)
C - Outer circumferential lamellae
D - Volkmann's (perforating) canal
E - Periosteum
F - Haversian (central) canal
G - Endosteum
Bone is a specialized connective tissue composed of what?
Intercellular calcified material (bone matrix)
Osteoblasts, osteoclasts, osteocytes
What do osteoblasts secrete?
Osteoid (Organic matter of bony matrix) which is subsequently calcified by the deposition of calcium salts.
What cells form new bone?
Osteoblasts
What cell is responsible for bone resorption and how?
Osteoclasts
Secretes acid and lysosomal enzymes
Periosteum consists of ____ and ____ layers.
Fibrous and osteogenic
T/F: Periosteum covers all surfaces of the bone.
False, it is absent on the articulating surfaces and at sites where tendons and ligaments insert on the bone.
What lines the marrow cavity and what is its composition?
Endosteum
A single layer of squamous cells, osteoblasts and osteoclasts
Where do compact bone and spongy bone occur?
Compact bone - Outer shells of the diaphysis and epiphyses
Spongy bone - Interior of the epiphysis
What does compact bone consist of?
Osteons or Haversian systems
Outer and inner circumferential lamellae
Interstitial lamellae
What does each osteon consist of?
A central canal surrounded by concentric lamellae, and lacunae containing osteocytes between the lamellae
What connects the central canals?
Perforating (Volkmann's) canals
What is in the central canal?
Blood vessels
Nerves
Loose CT
What are the two types of ossifications and where are they found?
Intramembranous ossification - skull bones (except base of the skull)
Endochondral ossification - Appendicular skeleton, vertebral column and bones of the base of the skull
T/F: Skeletal muscle myocytes have multiple oval nuclei located centrally.
False, they have multiple nuclei but the nuclei are located peripherally.
What are myofibrils composed of?
Thick myofilaments (primarily myosin)
Thin filaments (actin, troponin, tropomyosin)
What are the structures of the muscle from largest to smallest and the membranes around each?
Muscle (Epimysium)
Bundles (Perimysium)
Myofiber (Endomysium)
Myofibril
Myofilaments (actin & myosin)
What are the A band, I band and Z line?
A band - where thick and thin myofilaments overlap
I band - only thin myofilaments present
Z line - dark transverse line bissecting the I band
What is the smallest unit of the contractile apparatus of the muscle?
The sarcomere, which is between two adjacent Z lines.
What does the sarcoplasm contain and what covers it?
Smooth ER (sarcoplasmic reticulum)
Glycogen
Mitochondria
Myoglobin
Covered by the sarcolemma
What are satellite cells?
Represent inactive myoblasts that can be activated upon injury to initiate some regeneration of muscle fibers. Spindle-shaped cells with heterochromatic nuclei, located adjacent to the myocytes.
T/F: Red muscle fibers are fast-twitch.
False, red muscle fibers are slow-twitch, white muscle fibers are fast-twitch.
T/F: White fibers are larger with few mitochondria.
True, red fibers are smaller, rich in myoglobin and mitochondria.
What separates cardiac muscle myocytes?
Intercalated discs
T/F: Cardiac muscle myocytes have a single nucleus located in the center of the cell and branch.
True
Cardiac - branching (anastomosing), striated muscle, single nucleus in middle
Skeletal - non-branching, striated muscle, multiple nuclei on periphery
How do purkinje fibers differ from other cardiac muscle myocytes?
They have less myofibrils and located on the periphery.
What are the specialized impulse conducting fibers?
Purkinje fibers
What cells are elongated, spindle-shaped with a single elongated centrally located nucleus and an acidophilic cytoplasm?
Cavities of the brain and spinal cord, and in the space within the meninges.
What are the two parts of the neuron?
Nerve cell body (perikaryon)
Neuronal processes (axon and dendrites)
What type of neuron has one axon and multiple dendrites?
Multipolar
What type of neuron has one axon and one dendrite?
Bipolar
What type of neurons have one process that bifurcates into central and peripheral branches?
Unipolar, e.g. sensory ganglia
What is part of the Nissl substance in neurons?
Aggregation of rER and ribosomes
Where can you find eccentric nuclei in nerve cells?
Autonomic ganglia
What are the properties of the nucleus of nerve cells?
Centrally placed, ovoid or spherical, and relatively euchromatic
Eccentrically placed nucleus in the neurons of autonomic ganglia
Prominent nucleolus
Sex chromatin (Barr body) may be evident in the vicinity of the nucleolus in cats and rodents.
What is present in the cytoplasm of nerve cells?
Nissl substance (aggregation of rER and ribosomes)
Neurofilaments (cytoskeleton)
Microtubules (rapid transport of membrane-bound organelles)
Prominent golgi complex (secretes neurotransmitter and neurohormones)
Numerous mitochondria
Lipofuscin pigments (residue of lysosomal activity)
What structure is missing from the dendrites?
Golgi complexes
What is present on the synaptic sites of dendrites?
Thick band of electron-dense material, representing protein (receptor, channels, enzymes, etc.) responsible for postsynaptic activity
What are dendritic spines?
Gemmules, which consist of a membrane sac containing dense material.
What is the origin and terminal branches of axons?
Origin - axon hillock
Terminal - telodendrites
Where are the terminal bulbs and what do they include?
The ends of each terminal branch
Neurotransmitter molecules, packaged and stored within a synaptic vesicle
What are in the terminal branches and what do they contain?
Synaptic vesicles - neurotransmitter molecules
Secretory vesicles - Neuromodulaters (agents that augment neurotransmitter effects) and neurohormones (oxytocin and vasopressin in hypothalamic neurons)
What is the area between 2 neurons or a neuron and other effector cells?
What are groups of nerve cell bodies in the brain called?
Nuclei
Where is the grey matter and white matter in the cerebellum?
Grey matter on the outside, white matter on the inside (opposite of spinal cord and medulla)
What are the layers of the cerebral cortex in order from most exterior?
Molecular layer
External granular
External pyramidal
Internal granular
Internal pyramidal
Fusiform layer
What are the layers of the cerebellar cortex?
Outer molecular layer
Intermediate Purkinje cell layer (single layer of piriform cells, which send their ramified dendrites into the molecular layer, axons into the white matter)
Inner granular layer
What are the 3 meninges?
Dura mater
Arachnoid
Pia Mater
What's the term for the arachnoid and pia mater?
Leptomeninges
What produces the cerebrospinal fluid (CSF)?
The choroid plexuses in ventricles; by exiting through the lateral aperture it enters the subarachnoid space
Where are the epidural and subarachnoid spaces?
Epidural - Between the bone and dura mater
Subarachnoid - between the arachnoid and pia mater
