Histology Tissues Groups of cells similar in

slide1. Histology<br>
slide2. Tissues Groups of cells similar in structure and function
- the structure plays a role into the function

The structure and function complement each other<br>
slide3. Types of Tissues Epithelial tissue
Connective tissue
Muscle tissue
Nerve tissue

Atoms to Molecules to Cells<br>
slide4. Tissue Characteristics Differences between the tissue classes
Types and functions of cells
Characteristics of matrix (extracellular matrix)
Fibrous proteins
Ground substance – thick or thin
Clear gels (ECF, tissue fluid, interstitial fluid, tissue gel)
Rubbery or stony in cartilage or bone<br>
slide5. Tisssue Characteristics Space occupied by cells versus matrix
Connective tissue cells are widely separated
Little matrix between epithelial and muscle cells<br>
slide6. Cardiac Muscle- one nucleus in cardiac muscle<br>
slide7. Bone tissue<br>
slide8. Skeletal muscle - alternating dark and white patterns in skeletal muscles<br>
slide9. Smooth Muscle - they do not have alternating dark and light muscles<br>
slide10. Smooth Muscle<br>
slide11. Epithelial Tissue Two main types
- Covering and lining epithelia
- on external and internal surfaces

Glandular epithelia
Secretory tissue in glands<br>
slide12. Glandular Epithelia ge – glandular epithelia lp – lamina propria<br>
slide13. Epithelial Tissue Layers of closely adhering cells
Flat sheet with upper surfaces exposed to the environment or an internal body cavity
No blood vessels
Underlying connective tissue supplies oxygen
Rests on basement membrane
Thin layer of collagen and adhesive proteins
Anchors epithelium to connective tissue<br>
slide14. Basement Membrane<br>
slide15. Basement Membrane Not only an anchoring gel but also provides nutrients to the epithelium<br>
slide18. Squamous – covering
Cuboidal and Columnar – absorption
The nucleus of columnar cells are found on the lower third of a cell<br>
slide19. Squamous<br>
slide20. Simple Squamous 1 layer of flat cells<br>
slide21. Serous Membranes – watery membrane<br>
slide22. Small intestine – has epithelial tissue lining the inside and outside
Outside of small intestine – serous membrane
Outer layer of the heart – serous membrane
What is the common feature of the small intestine and the heart?<br>
slide23. Heart is constantly pumping – the serous membrane also reduces wear and tear
Small intestine – produces watery secretions
- the water in the serous membrane reduces friction and therefore reduces wear and tear<br>
slide24. Simple Squamous – Alveoli<br>
slide25. Simple squamous – alveoli<br>
slide26. Surrounding the alveoli air sacs are capillaries
Alveoli – capillaries for oxygenation and removal of carbon dioxide
Allows for rapid exchange if you have simple squamous epithelium<br>
slide27. Simple Cuboidal Picture<br>
slide28. Simple Cuboidal Epithelium Found in areas of secretion and excretion
Kidneys<br>
slide29. Renal Tubules<br>
slide30. Renal Tubules<br>
slide32. Simple Cuboidal Epithelium One layer of cube-shaped cells<br>
slide33. Simple Columnar Epitheliumm<br>
slide34. Simple Columnar Epithelium Tallest of the epithelial cells
Found in small intestines – almost all of absorption of nutrients is found here<br>
slide35. Small Intestine: Villi<br>
slide36. Villi – finger-like extensions<br>
slide37. Lumen – hollow opening within an organ<br>
slide38. Crypts<br>
slide39. Villi – in the apical surface are microvilli<br>
slide40. Microvilli – they form the brush border
Small extensions of the cell<br>
slide41. The taller the cells the higher the chance of absorption
The microvilli increases the absorptive area by increasing the height of cells
Whenever you see cells with microvilli you should think that these cells are used to absorb everything<br>
slide42. Villi and Goblet Cells<br>
slide43. Goblet cells – produce mucus<br>
slide44. Pseudostratified Columnar Epithelium Stratified – multi-layered
- every single cell originates on one exact membrane but they are of different heights that is why they look stratified
Respiratory mucosa<br>
slide45. Ciliated Epithelium – respiratory mucosa - lines the conducting airway of the lungs<br>
slide46. Respiratory Mucosa Goblet Cells Secrete mucus and line the conducting airways
Very sticky secretion
Release a protein called Mucin
Mucin combines with water and it becomes mucus
We want to clear the air before it reaches the our air sacs so that it would not damage our lungs<br>
slide47. Fallopian tubes in females<br>
slide48. Which one moves? Cilia or microvilli?<br>
slide49. Stratified Squamous Epithelium 2 major types
a. keratinized
b. non-keratinized<br>
slide50. Stratified Squamous Non Keratinized – wet areas of the body<br>
slide51. Stratified Squamous Epithelium Non Keratinized – all cells are alive Oral mucosa
Inner lining of the vagina
Lining of the esophagus

Wet, slippery areas<br>
slide52. Epithelial Tissue – high turnover meaning rapid change of cells like every 2-3 days
- mitosis is fast<br>
slide53. Stratified Squamous Keratinized<br>
slide54. Melanin – shields us from ultraviolet rays<br>
slide55. Keratinocytes The most abundant type of cells
Dead tough cells
Dead cells will exfoliate off<br>
slide56. Stratified Cuboidal<br>
slide57. Stratifed Cuboidal Quite rare in the body
Found in some sweat and mammary glands
Testicles
Typically two cell layers thick<br>
slide58. Stratified Cuboidal: Sweat Glands<br>
slide59. Stratified Cuboidal: Seminiferous Tubules of the Testes<br>
slide60. Transitional Epithelium Coolest of them all
Either round or flat<br>
slide62. Transitional Epithelium Change depending on how much stress you apply
Found in the urinary system
- bladder, ureters, urethra<br>
slide64. Glandular Epithelia A gland is one or more cells that makes and secretes an aqeuous fluid
Classified by:
- Site of product released
- Structure of the gland (endocrine, exocrine)
- Distance travelled by secretion
- Relative number of cells forming the gland – unicellular (e.g., goblet cells) or multicellular<br>
slide65. Endocrine glands – secrete into blood vessels
Exocrine glands – have ducts – ducts open into body surfaces<br>
slide66. Pancreas Is a mixed gland
It has endocrine and exocrine functions
Most of it is exocrine gland
98% is exocrine in function, secretes digestive enzymes – pancreatic secretions go into the stomach<br>
slide67. Pancreas<br>
slide68. Pancreatic secretion should not be going outside of the body
2% of the pancreas is endocrine – secretion of insulin and glucagon<br>
slide70. Main job of a cell is to produce proteins
For every amino acid you make you have to burn ATP
Golgi Apparatus – packages proteins
for goblet cells it is the packaged mucin<br>
slide71. Goblet Cell – endocrine or exocrine?
- short distance of travel of mucin<br>
slide72. Exocrine Glands<br>
slide74. Sebaceous glands – oil releasing glands<br>