Exam 1 Flashcards
What is a stereomicroscope?
A dissecting microscope
What are the steps in tissue processing?
Fixation -> Dehydration -> Clearing -> Infiltration -> Embedding
What solution is used for tissue fixation?
10% buffered formalin
How thin must tissue samples be cut?
1-7 micrometers
Silver stain- what does it stain & what color?
Reticular/nerve fibers; black (yellow background)
PAS (Periodic Acid Schiff)- what does it stain and what color?
Basement membrane & carbohydrates; magenta
What is the other name for cytosol?
Hyaloplasm
What is the other name for cell inclusions within cytoplasm?
Paraplasm
What are 2 examples of multinucleated cells?
Skeletal muscle cells, osteoclasts
Euchromatic nucleus- characteristics & examples
Pale chromatin, active cell; neurons, hepatocytes, pancreatic acinar cells, serotoli cells
How is mitochondria involved with apoptosis?
Initiates apoptosis by releasing cytochrome C
In what cell type is the Golgi apparatus most developed?
Secretory cells
What protein do proteasomes require for intracellular digestion?
Ubiquitin
Lysosomes- enzyme type
Hydrolase
Peroxisomes- enzyme type
Catalase
What are the 2 microfilament types?
Actin & myosin
What is an example of an intermediate filament?
Keratin
What is an example of microtubules?
Cilia
Where are tonofilament intermediate filaments found?
Epithelium
Where are vimentin intermediate filaments found?
Mesenchymal cells
Where are desmin intermediate filaments found?
Muscle
Where is lipofuscin pigment found?
Muscle cells, cardiac cells
Where is hemosiderin pigment found?
Spleen, liver
Where is glycogen found?
Liver, muscle, neurons
What are the differences between microvilli, cilia, & stereocilia?
Microvilli- absorptive, brush border
Cilia- motile, longer
Stereocilia- absorptive, large microvilli
What are the four types of tissues?
Epithelial, connective, muscular, nervous
What are the 3 types of epithelia and their functions?
Surface epithelia- form sheets to cover body/lumen surfaces
Glandular epithelia- secretory epithelia
Special epithelia- receptors (taste & hearing)
What does mesothelium mesoderm line?
Peritoneal, pleural, & pericardial cavities
What does endothelium mesoderm line?
Blood & lymphatic vessels, heart chambers
What does ectoderm epithelium line?
The surface of the body (epidermis of skin)
What does endoderm epithelium line?
GI tract, respiratory system, liver, pancreas, bladder
What is the difference between epithelial cells & mesenchymal cells?
Epithelial- little intercellular substance, many cells
Mesenchymal- lots of intercellular substance, few cells
What is the difference between basal lamina & basement membrane?
Basement membrane is the part of the basal lamina that is seen with light microscopy
What characteristics allow adhesion between epithelial cells?
Transmembrane glycoproteins, e-cadherins, intercellular adhesions
What are the functions of tight junctions?
Create seal around epithelial cells; prevent leakage of fluid
What are the functions of desmosomes?
Fasten cells together into sheets; like velcro; in skin
What are the functions of gap junctions?
Channels between adjacent cells for communication
What is the main characteristic of pseudostratified epithelium?
Cells look layered, but every cell contacts the basement membrane
Kartagener’s/Immotile Cilia Syndrome- cause & effect
Dynein arms missing from cilia/sperm tails
Chronic respiratory infection (no cilia in airway); male sterility
What type of epithelium can be keratinized?
Stratified squamous epithelium
True or false: keratinized cells have nuclei
False
Where is transitional epithelium found?
Lines urinary passages
What is the secretory unit of exocrine ducts?
Adenomere
What are the 3 shapes of duct adenomeres?
Tubular, acinar, alveolar
What are the 4 types of glands?
Serous, mucous, mixed, sebaceous
What are characteristics of serous glands?
Round nuclei, basophilic/acidophilic cytoplasm in basal/apical parts of cells, darker in color
What are characteristics of mucous glands?
Flat & heterochromatic nuclei @ base of cells, vacuolated (frothy)/ pale cytoplasm
What are characteristics of sebaceous glands?
Centrally located nuclei, pale/foamy cytoplasm
What is merocrine secretion?
No cytoplasm lost during secretion
What is apocrine secretion?
Some cytoplasm lost producing secretion
What is holocrine secretion?
Entire cell is the product of secretion
What is endocrine secretion?
Product is secreted into blood vessels
What are malignant tumors of connective tissue called?
Sarcomas
What cell types are resident cells of connective tissue?
Embryonic mesenchyme cells (fibroblasts, reticular cells, adipocytes, macrophages, mast cells)
What cell types are transient cells of connective tissue?
Hematopoietic stem cells (plasma cells, leukocytes, neutrophils, eosinophils, basophils, lymphocytes)
True or false: fibrocytes are active cells
False (fibroblasts are active; fibrocytes are inactive)
What are characteristics of type 1 collagen?
Resists tensile force; found in bone, dermis, tendons
What are characteristics of type 2 cartilage?
Resists compression; forms fibrils in cartilage
What are characteristics of type 3 collagen?
Reticular fibers; found in spleen, lymph nodes, liver
What are characteristics of type 4 cartilage?
Found in basement membranes
What color are collagen fibers?
White
What color are elastic fibers?
Yellow
What is connective tissue ground substance made up of?
GAGs, proteoglycans, glycoproteins
What is a proteoglycan composed of?
GAG + protein core
What is an abnormal accumulation of connective tissue fluid called?
Edema
What are the 4 types of proper connective tissue?
Loose, dense, reticular, adipose
What is the endocrine function of white adipose tissue?
Produces leptin (regulates body fat)
How does brown adipose tissue differ from white adipose tissue (look & function)?
Many lipid droplets per cell, mitochondria, found in hibernating/newborn animals for heat generation
True or false: cartilage is a avascular
True
What type of cell does cartilage differentiate from?
Mesenchymal cells
What cell type is present in perichondrium?
Chondroprogenital cells
Where is perichondrium present?
All hyaline cartilage EXCEPT articular, elastic cartilage (NOT present in fibrocartilage)
What molecular component makes cartilage strong & flexible?
Proteoglycans (present in ground substance)
What space surrounds each chondrocyte?
Lacunae
What functions do chondrocytes have?
Synthesis of ground substance & cartilage matrix
What is a cartilage isogenous group?
A cluster of 2-4 chondrocytes
What are histological characteristics of chondrocytes?
Small euchromatic nuclei, basophilic, lipid droplets
What is the main structural glycoproteins of cartilage matrix?
Chondronectin
Why is the cartilage matrix basophilic?
High concentration of GAGs
What is the territorial matrix of a chondrocyte?
Area immediately surrounding a chondrocyte; more basophilic than rest of matrix
What is cartilage interstitial growth?
Growth from within the cartilage; when a single chondrocyte replicates
What is cartilage appositional growth?
Growth from the periphery; from the perichondrium
What collagen type is present in hyaline cartilage?
Type 2 collagen
Where is hyaline cartilage located?
Fetal axial/appendicular skeleton, growth plates, articular cartilage, costo-Chandra junctions, nasal septum, larynx, tracheal rings, bronchi
What is another name for a growth plate?
Physis
What are the 3 zones of growth at a growth plate?
Zone of resting, zone of proliferation, zone of hypertrophy
Where is elastic cartilage located?
Larynx (epiglottis), external auditory canal, pinna of ear
True or false: all cartilage types have perichondrium
False
What type of collagen is present in fibrocartilage?
Type 1 collagen
Where is fibrocartilage located?
Intervertebral discs, mensci, insertions of tendons, mandibular symphysis, pubic symphysis
What type of collagen is found in bone organic matrix?
Type 1 collagen
What is present in the bone’s inorganic matrix?
Hydroxyapatite crystals
What is periosteum?
Connective tissue layer that covers outside of bones
What is endosteum?
Connective tissue layer that lines trabeculae of spongy bone
What is the bone extracellular matrix called?
Osteoid
What is the difference between woven bone and lamellar bone?
Woven bone- immature bone; fibers randomly arranged
Lamellar bone- mature bone; fibers arranged in parallel
How to osteocytes communicate?
Filopodia extended via bone canaliculi (tunnels within bone)
True or false: osteoblasts have lacunae
False (only osteocytes have lacunae when in mineralized matrix)
What are the functions of osteoclasts?
To remodel bone in response to growth/mechanical stress; to maintain Ca homeostasis
What are bone trabeculae?
Compact bone; where osteocytes are located
What is intramembranous ossification?
Occurs within membranes of mesenchymal tissue (immature); flat bones of skull
What is endochondral ossification?
Bone develops from cartilage at ossification centers/growth plates; most bones
What is the functional unit of mature bone?
Osteon
What is at the center of each osteon?
Haversian canal
What hormone increases osteoclast activity?
Parathyroid Hormone
True or false: synovial cells are epithelial cells
False (connective tissue cells that look like epithelium)
What is the main component of synovial fluid?
Hyaluronic acid
What are the functions of synovial fluid?
Nutrition, lubrication, protection of articular surfaces
What other type of tissue is often found within elastic cartilage?
Adipose tissue
Which part of a long bone contains the primary ossification center: the diaphysis or the epiphysis?
The Diaphysis (the epiphysis has the secondary ossification center)