Histology (Tissues) (Questions) Flashcards
What is histology?
Histology is the study of tissues.
What is a tissue?
A tissue is a group of cells with similar structure and function, surrounded by interstitial fluid.
What are the four major tissue types?
The four major tissue types are:
1. Epithelial Tissue
2. Connective Tissue
3. Muscle Tissue
4. Nervous Tissue
What are cell junctions?
Cell junctions are points of contact between adjacent cells, formed by cell membrane proteins.
What are the three types of cell junctions?
The three types of cell junctions are:
1. Tight Junctions
2. Anchoring Junctions
3. Gap Junctions
What is the function of tight junctions?
Tight junctions form a tight seal between cells, preventing materials from passing between them and stopping integral proteins from moving between cell surfaces.
What do anchoring junctions do?
Anchoring junctions fasten cells to each other and/or extracellular material, effectively “riveting” them together.
How do gap junctions function?
Gap junctions are open channels that interconnect the cytosols of adjacent cells, allowing ions and small molecules to pass and enabling tissues to function as a unit.
What are the characteristics of epithelial tissue?
Epithelial tissue covers body surfaces, lines cavities, has one free surface, little extracellular space, is avascular, and has a basement membrane.
What is the function of muscle tissue?
Muscle tissue is contractile, allowing for movement.
What type of tissue is connective tissue?
Connective tissue primarily supports and connects other tissues.
What role does nervous tissue play?
Nervous tissue is responsible for sensation and signaling.
How are epithelial tissues classified?
Epithelial tissues are classified by the number of cell layers and the shape of cells in the apical layer.
What are the classifications based on cell layers?
Simple: one layer
Stratified: more than one layer
What are the shapes of cells in epithelial tissues?
Squamous: flattened
Cuboidal: round or cube-shaped
Columnar: rectangular
What are the types of simple epithelia?
Simple squamous
Simple cuboidal
Simple columnar
What is stratified squamous epithelium?
It is a protective type of epithelium with more than one layer, primarily found in areas subject to abrasion (e.g., skin).
What is pseudostratified epithelium?
It appears stratified due to varying cell heights but is actually a single layer of cells attached to the basement membrane.
What characterizes transitional epithelium?
Transitional epithelium can change shape and layering depending on stretching, found in the inner lining of the urinary system.
What are the main types of connective tissue?
- Connective Tissue Proper
- Cartilage
- Bone
- Blood
What are glandular epithelia?
Glandular epithelia are specialized for secretion, classified into exocrine (with ducts) and endocrine (ductless) glands.
What are the three cell types found in connective tissue?
- -BLAST: create matrix (e.g., osteoblast)
- -CYTE: maintain matrix (e.g., osteocyte)
- -CLAST: break down matrix (e.g., osteoclast)
What is the primary function of connective tissue?
Connective tissue primarily supports and connects other tissues, with cells separated by an extracellular matrix.
What are the characteristics of cartilage?
Cartilage is avascular, has large amounts of matrix, and contains chondrocytes and chondroblasts.
What are the components of the connective tissue matrix?
The matrix is composed of fibers (collagen, elastic, reticular) and ground substance (water and organic molecules).
What types of cartilage exist?
- Hyaline cartilage
- Elastic cartilage
- Fibrocartilage
What distinguishes bone from other connective tissues?
Bone has a rigid matrix with abundant collagen fibers, and inorganic calcium phosphate, and is very vascular.
What are the components of blood as a connective tissue?
Blood is a fluid connective tissue composed of red blood cells, white blood cells, platelets, and plasma (the extracellular matrix).
What are the three types of muscle tissue?
- Skeletal (striated)
- Cardiac (striated)
- Smooth (non-striated)
What are the two main cell types in nervous tissue?
- Neurons: conduct electrical impulses
- Glial cells: support and protect neurons
