Unit 2: Ch 5 (Histology) Flashcards
(74 cards)
1
Q
Glands*
- Description
- Parts
- Components
- Types
A
- Function: Move/secrete substances
- Parts: Stroma & parenchyma
- Components: Capsule & septa or trabeculae (further categorized into lobes/lobules or globule/globules
-
Types:
- Endocrine glands
- Exocrine glands
- Some organs have both endocrine and exocrine functions (ie liver, gonads, pancreas)
2
Q
-blasts
A
Immature cell
3
Q
-cyte(s)
A
Mature cell
4
Q
Adherens junction*
[review lecture audio]
A
- A protein complex located at the junction between epithelial cells, which are subjected to stretching and pulling, yet require tight contact between them so they can function as a single unit
- An element of the cell-cell junction in which cadherin receptors bridge the neighboring plasma membranes via their homophilic interactions.
- Cadherins associate with cytoplasmic proteins called catenins, which in turn bind to cytoskeletal components, such as actin filaments and microtubules
5
Q
Adhesive Glycoproteins
A
- Bind tissue components together
- Mark paths that guide migrating embryonic cells to their destinations in a tissue
6
Q
Adipose Tissue*
- Cells
- Blood supply
- Functions
- Locations
A
- Cells:
- Adipocytes
- Filled with triglycerides
- Blood Supply: Vascular
- Functions
- Contributes to body contours
- Anchors and cushions organs
- Provides thermal insulation (white/yellow & brown fat)
- Locations
- Subcutaneous fat beneath the skin
- Examples: Breast, heart surface, mesenteries, surrounding organs such as kidneys & eyes
- Notes
- Nucleus always found on the periphery of the cell; pressed against the plasma membrane
7
Q
Apocrine Secretion
A
- Bud their secretions off through the plasma membrane producing extracellular membrane-bound vesicles
- The apical portion of the secretory cell of the gland pinches off and enters the lumen
- Found primarily in the breast of lactating mammals (i.e. the mammary glands are apocrine glands)
8
Q
Areolar Tissue Functions
A
- Binds epithelial cells to deeper tissues
- Allows passage of nerves and blood vessels through to other tissues
- Arena for immune defense
9
Q
Areolar Tissue*
- Description
- Cells
- Fibers
- Blood supply
A
- The most common, plentiful, and diverse tissue
- Nearly every epithelium rests on a layer of areolar tissue, whose blood vessels provide the epithelium with nutrition, waste removal, and a supply of leukocytes
- Cells: All 6 types
- Fibers
- All 3 types
- Random directions
- Blood supply: Vascular
10
Q
Biopsy
A
The removal and microscopic examination of a sample of living tissue
11
Q
Blood*
- Components
- Blood supply
- Functions
A
- Components
- Collectively called formed elements
- Erythrocytes / Red blood cells (RBCs)
- Leukocytes / White blood cells (WBCs)
- Blood platelets
- Doesn’t exhibit fibers, except when it clots
- Collectively called formed elements
- Blood supply: Vascular
- Functions
- Transports cells & dissolved matter through blood vessels
12
Q
Bone Types*
A
- Spongy bone (internal portion of bone)
- Compact bone (hard & strong with calcium and phosphate molecules)
13
Q
Brown Fat*
A
- Mainly in fetuses, infants, and children
- Concentrated in fat pads in the shoulders, upper back, and around the kidneys
- Stores lipids in the form of multiple globules rather than one large globule
- Notes
- Color comes from the abundance of blood vessels and enzymes in its mitochondria
- Mitochondria oxidative pathway is not linked to ATP synthesis
- Oxidized fat energy is released as heat
- Hibernating animals accumulate brown fat in preparation for winter
14
Q
Cartilage*
- Description
- Cells
- Fibers
- Blood supply
- Functions
- Locations
A
- Start as chondroblasts that become trapped in lacunae, and then become chondrocytes surrounded by perichondrium _(_only in hyaline and elastic cartilage)
- Matrix is rich in chondroitin sulfate
- Surrounded by perichondrium (only the hyaline & elastic fibers)
- Cells
- Chondroblasts
- Chondrocytes
- Fibers
- Hyaline
- Collagen
- Fibrocartilage
- Blood supply
- Avascular
- Functions
- Provide shape and support
- Examples: ear, nose, thyroid cartilage (adam’s apple)
- Locations
- Fetal bones, ears, intervertebral discs, places of flexibility
- Notes
- Chondrocytes takes longer to heal because it is avascular, meaning that it relies upon diffusion for blood supply
15
Q
Cell Junctions*
- Description
- Functions
- Types
A
- The connection between one cell and another
- Enable cells to resist stress, communicate with each other, and control the movement of substances through tissues
- Types
- Tight junction (structural junction)
- Adherens (structural junction)
- Desmosomes (structural junction)
- Hemidesmosomes (structural junction)
- Gap junction (communicating junction)
16
Q
Chondro-
A
Cartilage
17
Q
Collagen fibers*
- Description
- Appearance
A
- Most abundant protein in the body
- Appearance
- Thicker than elastic fibers
- Glistening white appearance, often called white fibers
- Function
- Form the fibers of many connective tissues in places such as the dermis, tendons, and bones
- Important for the functionality of strength (the thicker it is, the stronger it is)
- Resist stretching
- Base of gelatin, leather, and glue
18
Q
Compact Bone*
- Cells
- Components
- Functions
- Locations
A
- Cells
- Osteoblasts/osteocytes
- Lacunae
- Structure
- Osteon: functional unit of a compact bone
- Periosteum
- Cells and matrix surround vertically oriented blood vessels in long bones
- Canaliculi: allows for communication/transportation of messages and physically connect osteocytes
- Components
- Calcium & phosphate molecules
- Functions
- Allows for communication and transportation of messages
- Physically connects osteocytes
- Locations: Surrounds spongy bone
19
Q
Cells found in the connective tissues*
A
- Adipocytes: Fat cells that provide insulation, shock absorption, and energy storage
- Fibroblasts: Create fibers of extracellular matrix
- Leukocytes: White blood cells (immunity/protection)
- Macrophages: Performs phagocytosis
- Mast cells: Release histamines
- Plasma cells: Antibodies and immunity
20
Q
Fibers that form the connective tissues*
- Fiber Types
A
- Ground substance/extracellular matrix
- Collagen fibers: strength
- Elastic fibers: Thin; allow for movement in tissue (ie heart and lung expansion)
- Reticular fibers: lymphatic & immune systems
21
Q
Connective Tissue Functions*
A
- Binding of organs
- Support
- Physical protection
- Immune protection
- Movement
- Storage
- Heat production
- Transport
22
Q
Connective Tissue Ground Substance
A
- Absorbs compressive forces and, like the styrofoam packing in a shipping carton, protects the more delicate cells from mechanical injury
- Usually has a gelatinous to rubbery consistency resulting from 3 classes of large molecules:
- Glycosaminoglycans
- Proteoglycans
- Adhesive glycoproteins
23
Q
Connective tissue types*
A
- Loose Connective Tissue
- Areolar
- Reticular
- Dense Connective Tissue
- Dense regular
- Dense irregular
- Notes
- The anatomical difference between the two types is how much space is between the cells
- The difference between dense tissue is how the collagen fibers are arranged in a plane
24
Q
Connective Tissue*
- Description
- Types
- Parts
A
- Most abundant, widely distributed, and histologically variable of the primary tissues
- Connective tissue types
- Fibrous tissue
- Loose connective tissue
- Areolar
- Reticular
- Dense connective tissue
- Dense regular
- Dense irregular
- Loose connective tissue
- Adipose tissue
- Cartilage
- Bone
- Spongy
- Compact/Dense
- Blood
- Fibrous tissue
- Parts
- Cells
- Matrix (aka extracellular matrix)
25
Cutaneous Membrane
* The largest membrane of the body; the skin
* Stratified squamous epithelium (epidermis - _keratinized_) that rests on a layer of connective tissue (dermis)
26
Dense Irregular Connective Tissue\*
* Cells
* Fibers
* Blood supply
* Functions
* Locations
* Cells
* Few visible
* Located in _3 planes_
* Fibers
* Collagen
* Randomly arranged
* Blood supply
* Vascular
* Scarce
* Functions
* Withstands unpredictable stresses
* Locations
* Skin
* Around viscera such as liver, kidney, spleen
* Fibrous sheaths around cartilages and bones
27
Dense Regular Connective Tissue\*
* Cells
* Fibers
* Blood supply
* Functions
* Locations
* Cells
* Fibroblasts (compressed in the nuclei)
* Fibers
* Elastic
* Collagen
* Parallel; wavy-like pattern
* Blood supply
* Scarce blood vessels (results in slow healing)
* Functions
* Ligaments tightly bind bones together and resist stress
* Tendons attach muscle to bone and transfer muscular tension to bones
* Locations
* Tendons
* Ligaments
28
Desmosomes
* Functions
* Locations
* Functions
* Serve to keep cells from pulling apart and enable tissues to resist mechanical stress
* A patch that holds cells together somewhat like the snap on a pair of jeans
* Cannot prevent substances from passing around them and going between the cells
* Locations
* Common in the epidermis, the epithelium of the uterine cervix
* Notes
* Not continuous
* The basal cells of epithelium are similarly linked to the underlying basement membrane by half-desmosomes called _hemidesmosomes_
29
Anatomical & physiological differences between keratinized and nonkeratinized epithelia\*
* Anatomical
* Presence or lack of keratin
* Physical
* Nonkeratinized have living cells throughout
* Keratinized are superficial layers that contain dead cells
30
Elastic Fibers\*
* Description
* Appearance
* Functions
* Locations
* Ability of the skin, lungs, and arteries to spring back after they are stretched
* Elasticity is not the ability to stretch, but the tendency to recoil when tension is released
* Made of elastin coated with a glycoprotein (fibrillin)
* Appearance
* Thinner than collagenous fibers
* Branch and rejoin each other
* Always covered by perichondrium
* Functions
* Provides flexible, elastic support
* Locations
* External ear
* Epiglottis
31
3 Embryonic Tissue Layers\*
* Embryonic development is the first 8 weeks after conception
* All tissues arise from the following germ layers
* _Ectoderm_
* Gives rise to the epidermis (outermost cutaneous layer) and nervous system
* _Endoderm_
* Gives rise to mucous membranes lining (the beginning and ending) of the digestive and respiratory tracts
* Digestive glands
* Reproductive system
* _Mesoderm_
* Gives rise to muscle, bone, blood
* Important for connective tissues
32
Epithelial Cell Surfaces & Membrane\*
* Apical surface
* Most superior/superficial layer
* Lateral surface
* 2 lateral surfaces for each epithelial cell
* Found on the periphery/sides
* Basal surface
* Most inferior layer
* Connects with the basement membrane
* Basement membrane
* Anchor for epithelial cells
* Binds growth factors from below that regulate epithelial development
* Contains collagen, glycoproteins, and other protein-carb complexes
33
Epithelial Tissues\*
* Description
* Classifications
* Functions
* Locations
* Typically exhibit a high rate of mitosis
* Distinct apical, lateral & basal surfaces
* Always _avascular_: relies on diffusion to maintain homeostasis
* Classifications
* Simple epithelial
* Squamous, cuboidal, columnar, pseudostratified
* Stratified epithelial
* Squamous (keratinized/nonkeratinized), cuboidal, columnar, urothelium/transitional
* Functions
* Secretion
* Absorption
* Locations
* Cover organs
* Line organs
* Glandular: secretions from glands
34
Excretion
* A gland product that is not useful to the body (such as urine and bile)
35
Exocrine Gland Classification\*
* Classified according to the branching of their ducts and the appearance and extent of their secretory portions
1. # of cells present
* _Unicellular_
* _Multicellular_
2. Type of duct present
* _Simple_: a single unbranched duct
* _Compound_: have a branched duct
3. Shape of the secretory portion
* _Tubular_: looks like a test tube
* _Acinus_: circular/round
* _Tubuloacinar_: combination between tubular and round
36
Fibrocartilage
* Description
* Functions
* Locations
* Strongest of the 3 fibers
* Identified by chondrocytes being in lines or small clusters
* Parallel collagen fibers
* _Never_ has a perichondrium
* Functions
* Resists compression and absorbs shock
* Often a transitional tissue between dense connective tissue and _hyaline_ cartilage
* Locations
* At joints where tendons insert on bones near articular hyaline cartilage
* Pubic symphysis
* Intervertebral discs
* Menisci; pads of shock-absorbing cartilage in knee joint
37
Gap Junction
* A communicating junction
* Formed by a connexon, which consists of 6 membrane proteins arranged in a ring, somewhat like the segments of an orange, surrounding a water-filled channel
* Example: heart
38
Glands
* **Endocrine**
* Secrete substances that circulate through the bloodstream
* ie hormones, thyroid and pituitary glands
* **Exocrine**
* Groups
* Merocrine/Eccrine
* Secrete their substances by exocytosis
* Uses exocytosis
* ie salivary, tears, sweat
* Apocrine
* A portion of the secreting cell's body is lost during secretion
* Uses cytoplasm in the cell
* ie breast milk
* Holocrine
* The entire cell disintegrates to secrete its substances
* ie oil glands
* Types
* Serous
* Mucous
* Sebaceous
39
Glycosaminoglycans (GAG)
* Composition
* Function
* **Composition**: _Amino sugars_ and _uronic acid_
* **Function**:
* Regulate water and electrolyte balance of tissues
* Negatively charged and tend to attract sodium and potassium ions, which in turn cause them to absorb and retain water
* **Example**: The most common GAG is _chondroitin sulfate_
40
Goblet Cells
* Always found with columnar cell shapes
* Large cells that contain mucus
* Acts as a lubricant
* Traps pathogens
41
Hyaline Cartilage
* Appearance
* Functions
* Locations
* Appearance
* Clear, glassy matrix; cannot see individual fibers
* Collagen fibers
* No perichondrium
* Functions
* Eases joint movements
* Holds airway open during respiration
* Moves vocal cords during speech
* Locations
* Covers the ends of bones at movable joints
* Supportive rings and plates around trachea and bronchi
* A boxlike enclosure around the larynx
* Much of the fetal skeleton
42
Lateral surface
* The "sidewall" of a cell
43
Leukocytes or White Blood Cells (WBCs)
* Description
* 5 Types
* Defense against infection and other diseases
* Primarily in connective tissues
* Larger than RBCs
* Conspicuous nuclei
* 5 types (distinguished in part by shape)
* Neutrophils
* Eosinophils
* Basophils
* Lymphocytes
* Monocytes
44
Loose Connective Tissue Types
* Areolar Tissue
* Reticular Tissue
45
Matrix
* Fibrous proteins
* Ground substance
* Tissue fluid
* ECF or interstitial fluid
46
Membrane Types\*
* Mucous membrane (mucosa)
* Serous membrane (serosa)
* Cutaneous membrane
* Synovial membrane
47
Mucous Glands
* Found in the oral and nasal cavities
* Secrete a glycoprotein, called _mucin_
* After it is secreted, mucin absorbs water and forms the sticky product, _mucus_
48
Mucous Membrane (Mucosa)\*
* Description
* Functions
* Locations
* Lines passages that open to the exterior environment
* Have _goblet_ cells
* Consists of 2-3 layers
* Muscularis mucosae: smooth muscle (involuntary)
* Lumina propria
* Epithelium
* Functions
* Absorptive
* Secretory
* Protective functions
* Locations
* Digestive, respiratory, urinary, and reproductive tracts
49
Muscular Tissue
* Definition
* Representative Locations
* Tissue composed of elongated, excitable muscle cells specialized for contraction
* Locations
* Skeletal muscles
* Heart (cardiac muscle)
* Walls of viscera (smooth muscle)
50
Nervous Tissue
* Description
* Locations
* Contain excitable cells specialized for rapid transmission of coded information to other cells
* Locations
* Brain
* Spinal cord
* Nerves
51
Osteo-
Bone
52
Pseudostratified epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Appears multi-layered, but all cells reach the basement membrane
* Often appear columnar or triangular
* Has _goblet_ cells
* Technically a simple epithelial cell
* Functions
* Secrets and propels mucus
* Locations
* Respiratory tract from the nasal cavity to bronchi
* Portions of the male urethra
53
Red Blood Cells (RBC)
## Footnote
*(aka Erythrocytes)*
* Most abundant
* Transport oxygen and carbon dioxide
* Look like pink discs with thin, pale centers and no nuclei
54
Reticular fiber\*
* Description
* Functions
* Locations
* Part of the basement membrane
* Thin collagen fibers coated with _glycoproteins_
* Forms supportive _stroma_ framework for lymphatic organs
* Locations
* Lymph nodes, spleen, thymus, bone marrow
55
Secretion
* A gland product that is useful to the body (such as an enzyme or hormone)
56
Secretion glands\*
* Serous glands
* Produce thin, watery secretions
* ie Perspiration, milk, tears, digestive juices
* Mucous glands
* Produce mucin
* ie respiratory system
* Mixed glands
* Contain both cell types and produce a mixture of the two types of secretions
* ie Salivary glands
57
Serous Glands
* Produce relatively thin, watery fluids such as perspiration, milk, tears, and digestive juices
58
Serous Membrane (Serosa)\*
* A smooth tissue membrane consisting of two layers of mesothelium, which secrete serous fluid
* Visceral layer: inner layer that covers organs in body cavities
* Parietal layer: lines the body wall
59
Simple columnar epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Tall/narrow cells
* Have _goblet_ cells
* Functions
* Absorption
* Secretion of mucus
* Movement of egg and embryo in the uterine tube
* Locations
* Inner lining of stomach, intestines, gallbladder, uterus
* Respiratory system
60
Simple cuboidal epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Squarish or round cells
* Single-layer
* Functions
* Absorption and secretion
* Production of protective mucous coat
* Movement of respiratory mucus
* Locations
* Often in glands
* Liver
* Thyroid
* Mammary
* Salivary glands
61
Simple squamous epithelial\*
* Appearance
* Function
* Location
* Appearance
* Thin & scaly
* "Fried egg" with a bulge
* Single-layer
* Functions
* Diffusion
* Secretes lubricating serous fluid
* Locations
* Air sacs of lungs, kidneys, inner lining of heart & blood vessels, serous membranes
62
Spongy Bone\*
* Cells
* Functions
* Locations
* Cells
* Trabeculae
* Covered by compact bone
* Functions
* Bone marrow
* Blood platelet formation
* WBC, RBC & stem cells
* Locations
* Heads of long bones and in middle of flat bones (ie sternum)
63
Stratified columnar epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Column shaped
* Multi-layered
* Have goblet cells
* Functions
* Protection
* Secretion
* Locations
* Rare; seen where two other epithelial types meet
* Pharynx, larynx, anal canal, male urethra
64
Stratified cuboidal epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Surface cells are square or round
* Functions
* Contributes to sweat secretion
* Secretes ovarian hormones
* Produces sperm
* Locations
* Sweat gland ducts
* Egg-producing vesicles of ovaries
* Sperm-producing ducts
65
Stratified squamous keratinized (cornified) epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Multi-layered
* Cells become increasingly flat and scaly toward the surface
* Covered with a layer of compact dead cells without nuclei
* Functions
* Resists abrasion and penetration by pathogenic organisms
* Retards water loss through the skin
* Locations
* Skin
* Palms and soles of feet
66
Stratified squamous _nonkeratinized_ epithelial\*
* Appearance
* Functions
* Locations
* Appearance
* Same as keratinized, without a layer of dead cells
* Have living cells throughout
* Functions
* Resists abrasion and penetration by pathogenic organisms
* Locations
* Tongue, esophagus, vagina, anal canal
67
Stratified urothelium epithelial\*
*(aka stratified transitional epithelial)*
* Appearance
* Functions
* Locations
* Similar to stratified squamous cells, but round, not flat, and often bulge at the surface
* The only epithelium that can be binucleated
* Functions
* Stretches to allow filling of urinary tract
* Protects underlying tissues from osmotic damage by urine
* Lines the organs of the urinary system
* Locations
* Unique to the urinary tract
* Urine is usually acidic and hypertonic to the intracellular fluid
* It would draw water out of the cells by osmosis and kill them if there were nothing to protect them
* Part of kidney, ureter, bladder, urethra
* Notes
* Outer phospholipid layer protected by _umbrella cells_
* The plasma membrane is thicker than usual and has dense patches called lipid rafts with embedded proteins called _uroplakins_
68
Synovial membrane\*
* Secrets synovial fluid around the joints
* Has "within normal limits" range
69
Tight Junctions
* Encircles an epithelial cell near its apical surface and joins it tightly to the neighboring cells
* Think of a plastic harness on a 6-pack of cans
* Interlocking proteins seal-off the intercellular space and make it difficult for substances to pass between cells and digesting the underlying connective tissue
* Help to prevent bacteria from invading the tissues, and they _ensure the most nutrients pass through the epithelial cells and not between them_
70
Tissue
* Two or more cells physically coming together with a common structure and function
* Composed of cells and matrix
* Matrix is composed of fibers and ground substance
71
4 tissue types & classes
* Epithelial
* Connective
* Nervous
* Muscular
* Skeletal
* Cardiac
* Smooth muscle
72
Vascular
* Has a blood supply; not dependent on diffusion for oxygen
* Opposite is _avascular_
73
White (or yellow) fat\*
* Description
* Function
* Appearance
* The most significant adipose tissue
* More abundant than brown fat
* Doesn't have as many mitochondria
* Has a single large, central globule of triglyceride
* Function
* More of a storage connective tissue as opposed to thermal regulation/cushioning
* Contributes to body contours such as breasts and hips
74
Why is blood in the connective tissue category?
* It is composed of more ground substance than cells
* It is produced by the connective tissues of the bone marrow and lymphatic organs