100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Bio 2311 Chapter 4 -6 Notes $10.99   Add to cart

Class notes

Bio 2311 Chapter 4 -6 Notes

 2 views  0 purchase

This is a comprehensive and detailed note on Chapter 4;Tissue level of organization 5;The integumentary system 6; Bones and bone structure for Bio 2311. *Essential Study Material!! *For you, at a price that's fair enough!!

Preview 4 out of 39  pages

  • September 11, 2024
  • 39
  • 2022/2023
  • Class notes
  • Prof. s. chakrabroty
  • All classes
All documents for this subject (15)
avatar-seller
anyiamgeorge19
Fundamentals of Anatomy & Physiology Study Guide CH 4 – 6
Chapter 4: The Tissue Level of Organization
An Introduction to Tissues
 Tissues
o Collections of specialized cells and cell products that perform specific functions
o Tissues in combination form organs, such as the heart or liver
o Histology is the study of tissues
4 – 1 Four Types of Tissues
 Four types of tissue
1. Epithelial
2. Connective
3. Muscle
4. Nervous
 Epithelial tissue
o Covers exposed surfaces
o Lines internal passageways
o Forms glands
 Connective tissue
o Fills internal spaces
o Supports other tissues
o Transport materials
o Stores energy
 Muscle tissue
o Specialized for contraction
o Skeletal muscle, heart muscle, and muscular walls of hollow organs
 Nervous tissue
o Carries electrical signals from one part of the body to another
4 – 2 Epithelial Tissue
 Epithelial tissue includes epithelia and glands
o Epithelia (singular, epithelium)
 Layers of cells covering internal or external surfaces
o Glands
 Structures that produce fluid secretions
 Functions of epithelial tissue
1. Provides physical protection
2. Controls permeability
3. Provide sensation
4. Produce specialized secretions
 Characteristics of epithelia

, o Polarity (apical and basal surfaces)
o Cellularity (cell junctions)
o Attachment (basement membrane)
o Avascularity (avascular)
o Regeneration
 Specialization of epithelial cells
1. Move fluids over the epithelium (protection)
2. Move fluids through the epithelium (permeability)
3. Produce secretions (protection and messaging)
 Polarity
o Apical surface
 Microvilli increase absorption or secretion
 Cilia on a ciliated epithelium move fluids
o Basolateral surface
 Integrity of epithelia is maintained by
1. Intercellular connections
2. Attachment to the basement membrane
3. Epithelial maintenance and repair
 Intercellular connections
o Support and communication
 Cell adhesion molecules (CAMs)
 Transmembrane proteins
 Proteoglycans act as intercellular cement
 Contain glycosaminoglycans such as hyaluronan (hyaluronic acid)
o Cell junctions
 Form bonds with other cells or extracellular material
1. Gap junctions
2. Tight junctions
3. Desmosomes
 Gap junctions
o Allows rapid communication
o Cells held together by interlocking transmembrane proteins (connexons)
o Allows small molecules and ions to pass
o Coordinate contractions in heart muscle
 Tight junctions
o Between two plasma membranes
o Adhesion belt attaches to terminal web
o Prevent passage of water and solutes
o Keep enzymes, acids, and wastes in the lumen of the digestive tract
 Desmosomes
o CAMs and proteoglycans link opposing plasma membranes
o Spot desmosomes
 Tie cells together

,  Allow bending and twisting
o Hemidesmosomes
 Attach cells to the basement membrane
 Attachment to the basement membrane
o Basal lamina
 Closest to the epithelium
o Reticular lamina
 Deeper portion of basement membrane
 Provides strength
 Epithelial maintenance and repair
o Epithelial cells are replaced by continual division of stem cells
 Located near basement membrane
4 – 3 Classification of Epithelia
 Classification of epithelia
1. Based on shape
o Squamous – thin and flat
o Cuboidal – square shaped
o Columnar – tall, slender rectangles
2. Based on layers
o Simple epithelium – single layer of cells
o Stratified epithelium – several layers of cells
 Squamous epithelia
o Simple squamous epithelia
 Absorption and diffusion
 Mesothelium
 Lines body cavities
 Endothelium
 Forms inner lining of heart and blood vessels
o Stratified squamous epithelia
 Protects against mechanical stresses
 Keratin adds strength and water resistance
 Cuboidal epithelia
o Simple cuboidal epithelia
 Secretion and absorption
 Glands and portions of kidney tubules
o Stratified cuboidal epithelia
 Relatively rare
 Ducts of sweat glands and mammary glands
 Transitional epithelia
o Tolerate repeated cycles of stretching without damage
o Appearance changes as stretching occurs
o Found in urinary bladder

,  Columnar epithelia
o Simple columnar epithelia
 Absorption and secretion
 Found in stomach, small intestine, large intestine
o Pseudostratified columnar epithelia
 Typically have cilia
 Found in nasal cavity, trachea, bronchi
o Stratified columnar epithelia
 Relatively rare
 Provide protection in pharynx, anus, urethra
 Glandular epithelia
o Glands are collection of epithelial cells that produce secretions
o Endocrine glands
 Releases hormones that enter bloodstream
 No ducts
o Exocrine glands
 Produces exocrine secretions
 Discharge secretions through ducts onto epithelial surfaces
 Gland structure
o Unicellular glands
o Multicellular glands
 Unicellular glands
o Goblet cells are unicellular exocrine glands
 In epithelia of intestines
 Secret mucin, which mixes with water to form mucus
 Multicellular exocrine glands are classified by
1. Structure of the duct
o Simple (undivided)
o Compound (divided)
2. Shape of secretory portion of the gland
o Tubular (tube shaped)
o Alveolar or acinar (blind pockets)
3. Relationship between ducts and glandular areas
o Branched (several secretory areas sharing one duct)
 Methods of secretion
1. Merocrine
2. Apocrine
3. Holocrine
 Merocrine secretion
o Released by secretory vesicles (exocytosis)
o Example: merocrine sweat glands
 Apocrine secretion
o Released by shedding cytoplasm

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller anyiamgeorge19. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

67096 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$10.99
  • (0)
  Add to cart