Histology-Study of tissue types

1
Histology-Study of tissue types

• Chap 4

2
Main tissue types

• Epithelial
• Connective
• Nervous
• Muscle tissue

3
Epithelial Tissue

• Coverings and boundries
• Functions
• Protection
• Absorption
• Filtration
• Excretion
• Secretion
• Sensory reception

4
Epithelial Tissue Characteristics

• Cellularity- cells packed close together
• Specialized contacts- communication and
  attachment between cells
• Tight Junctions
• Desmosomes
• Polarity- have a top and bottom
• Apical surface
• Basal surface

5
Epithelial Tissue Characteristics

• Supported by connective tissue
• Basement membrane
• Avascular but innervated- few blood vessels, has
  nerve fibers
• Regenerative- can repair easily

6
(No Transcript)
7
Simple vs Stratified epithelium cellsSquamous

• Simple - adapted for filtration and reducing
  friction (aveoli, body cavities, kidney-loop of
  Henle)
• Multilayered structure of stratified - adapted
  for surfaces exposed to wear and tear (skin,
  mouth, esophagus)

8
(No Transcript)
9
(No Transcript)
10
Cuboidal

• Simple (almost all)- secretion or absorption
  (pancreas, salivary glands Thyroid hormones)
• Stratified (rare) (along ducts of sweat glands)

11
(No Transcript)
12
Columnar

• Simple- Secretion, absorption, protection from
  chemical stress (small intestine, stomach)
• Psudostratified typically have cilia (nasal
  cavity, trachea, male reproductive tract)
• Stratified (rare) (small areas of pharynx,
  epiglottis, anus, mammary gland, urethra)

13
(No Transcript)
14
(No Transcript)
15
(No Transcript)
16
Glandular Epithelia

• Contain gland cells specialized for secretion
• Endocrine glands-hormones
• Pancreas, thyroid , thymus, pituitary
• Exocrine glands have tubular ducts to the
  surface
• Perspiration, tears, milk, mucus

17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
Goblet Cell
Figure 4.3b
21
For your pictures

• Simple Squamous- (lung)
• Stratified Squamous
• Simple cuboidal
• Simple columnar (cilliated)- (trachea)
• Pseudostratified columnar
• Transitional epithelial
• EC- Stratified Columnar

22
(No Transcript)
23
(No Transcript)
24
Connective Tissue

• Found throughout the body most abundant and
  widely distributed in primary tissues
• Connective tissue proper
• Cartilage
• Bone
• Blood

25
Functions of Connective Tissue

• Binding and support
• Protection
• Insulation
• Transportation

26
Characteristics of Connective Tissue

• Connective tissues have
• Mesenchyme as their common tissue of origin
• Varying degrees of vascularity
• Nonliving extracellular matrix, consisting of
  ground substance and fibers

27
Pg 121
28
(No Transcript)
29
(No Transcript)
30
Connective Tissue Proper

• Loose Connective tissues
• Areolar gel-like cushions
• Adipose fatty fuel reserve, insulation
• Reticular fiborous internal, cell support

31
(No Transcript)
32
(No Transcript)
33
(No Transcript)
34
Connective Tissue Proper

• Dense Connective tissue collagen fibers,
  elastin fibers (fibroblast cells)
• Regular attach muscle to bone, muscle to
  muscle, bone to bone (Ligaments and tendons)
• Irregular structural strength (Dermis of skin,
  submucosa of digestive tract)

35
(No Transcript)
36
(No Transcript)
37
Cartilage

• Solid matrix of Colloagen fibers (condrocytes-
  mature condroblasts)- avascular
• Hyaline very hard and solid connected to bone
• Elastic more flexible (ears, epiglottis)
• Fibrocarilage in between flex absorbs shock
  (between vertebra)

38
(No Transcript)
39
(No Transcript)
40
(No Transcript)
41
Bone

• -calcified matrix w/ collagen fibers ostoblast
  cells mineralize and become ostecytes in lacunae
  (cavities) - vascularized

42
(No Transcript)
43
Blood

• red and white bc

44
(No Transcript)
45
For your pictures

1. Embryonic- (fetal)
2. Areolar-loose
3. Adipose-loose
4. Reticular- loose (only 2 slides silver stained)
5. Dense regular- (collagenous fibers- regular)
6. Dense irregular-(collagenous fibers- irregular)
7. Hyaline cartilage
8. Elastic Cartilage
9. Fibrocartilage (fiberous)
10. Bone
11. Blood

Same slide
46
Nerve Tissue

• Function Respond to stimuli and transmit
  impulses.
• Generate and conduct electrical impulses
• Regulate and control body functions
• Cells are called neurons
• Composed of cell body, axon and dendrites.
• Single cell may run up to several feet long.
• Supporting cells
• Support
• Insulation
• Protection
• (Well discuss in detail in Chap 11)

47
(No Transcript)
48
Muscle tissue

• Myofilaments for movement
• Actin
• Myocin
• Look for striations perpendicular to fibers
• Lots of mitochondria

49
(No Transcript)
50
Muscle tissue types

• Skeletal- very striated
• Voluntary Muscle
• Cardiac more loose structure, striated
• Inertercolated discs (connection between
  branching cells)
• Smooth barely visible striations
• Involuntary Muscle

51
(No Transcript)
52
(No Transcript)
53
(No Transcript)
54
(No Transcript)
55
For your slides

• Nerve tissue
• Mammal Neuron motor nerve
• Muscle tissue
• Skeletal
• Cardiac
• smooth

56
Quiz yourself

• http//www.yvcc.edu/academics/biology/seveyka/Hist
  ology20Zoomer/histology_zoomer_page.asp
• http//www.keele.ac.uk/depts/ms/resources/anatomy/
  histologyimages/homepage.html
• Email me and Ill send you the links

57
Tissue Repair

• 1. Inflammation
• Trauma causes damaged cells , macrophages and
  mast cells to release inflammatory chemicals
• Capillaries dilate, allow WBC, clotting proteins
  and antibodies into damaged area
• Clots form to isolate area (hardening forms scab)

58
Tissue Repair

• 2. Organization restore blood supply
• Granulation tissue
• Capillaries
• Fibroblasts
• growth factors
• Collagen fibers

59
Tissue Repair

• 3. Regeneration and fibrosis
• Epithelial cells regenerate
• Collagen (fibrous tissue) contracts to pull edges
  together
• Some left behind to form scar tissue

60
(No Transcript)
61
(No Transcript)
62
Infections

• Simple
• Pimple or sore throat
• Regeneration only, no fibrosis
• No clotting
• Severe
• Destructive
• Scar tissue formed
• Scar tissue
• Mostly collagen fibers, shrink and compact
• Replaces original tissue type- does not function
  as original tissue type
• Very strong, not very flexible

63
Cancer

• Tumor or neoplasm loss of apoptosis (programmed
  cell death)
• Benign- polyp - localized extra growth of cells,
  encapsulated
• Malignant Metastasis spread to other parts of
  the body, often de-differentiate
• Oncogenes cancer causing genes
• Carcinogenic cancer causing chemical

64
(No Transcript)
65
Types of Cancer

• - Adenoma ? adenocarcinoma Epithelial glands
• Papilloma ? carcinoma epithelial squamous
• Nevus (mole)? melanoma melanocytes (pigmented
  skin cells)
• Sarcoma connective and muscle
• Lymphoma lymphatic tissue
• Leukemia blood
• Osteoma bone
• Condroma cartilage
• Lipoma adipose
• Fibroma fibrous connective tissue

66
Cancer treatment

• Surgery can be effective for benign tumors
• Systemic treatment
• Radiation Therapy
• Chemotherapy
• Kills ALL types of rapidly growing cells
• Unpleasant side effects
• Nausea/ vomiting
• Hair loss

67
USE OF HISTOCHEMISTRY TO DETECT INFECTIOUS
ORGANISMS
Silver stain (GMS) to detect presence of fungal
hyphae in tissue x200
Grams stain to detect bacteria in tissue (oil
immersion x1000)
68
MORE EXAMPLES OF HISTOCHEMISTRY
Fontana-Masson for melanocytes
Luxol Fast Blue for myelin
69
Review Assignment

• Read pg 142-143 (cancer)
• Scan Chap summary
• Pg 110-112 (cells)
• pg145-146 (histology)
• DO Review Questions
• Pg 112-113 (cells)
• Pg 147 (histology)
• Be sure to discuss all Crit think /Clinical App.
  Questions w/ a partner! We will go over these in
  class last ½ hr

70
(No Transcript)
71
(No Transcript)
72
(No Transcript)