Fibrous CT Flashcards
What structure separates CT from the outside environment?
Epithelium
What separates CT cells from each other?
ECM
What is ECM composed of?
A gel like (ground) substance with embedded protein fibers
What is ground substance?
It holds tissue fluid derived primarily from blood
Carries O2, CO2, nutrients and waste
What is connective tissue?
A microscopically and functionally diverse group of tissues that can be classified into major groups such as embryonic and adult CT
What can adult CT be further classified into?
Fibrous and specialized CT
Which classes of CT are considered to be fibrous?
Areolar, dense regular and dense irregular
Which CT classes are considered to be specialized?
Adipose, cartilage, bone and hematopoietic
What are the functions of CT?
Structural framework of the body, protection, supports and interconnects other tissues, energy storage, transport fluids, cells and dissolved chemicals throughout the body and defense against invasion of microorganisms
What are fibroblasts?
Cells of CT that produce collagen, elastin, reticular fibers, proteoglycans and glycoproteins
What are mesenchymal cells?
CT stem cells
What are adipocytes?
A CT cell type that stores and releases fats, provides a reserve for energy sources and removes lipids from the blood, stores it and released it into the blood stream when needed
Describe adipocytes structure
Closely packed with their nuclei pushed to the side by large fat droplets
What are chondrocytes?
A CT cell that produces and maintains cartilage components
What are osteoblasts/osteoclasts?
A CT cell type that produces and removes bone components
What are hematopoietic stem cells?
A CT cell that produces RBCs and immune cells
Which structures are considered to be the fibrous component of ECM of CT?
Collagen fibers, elastin and reticular fibers
What is the function of the collagen?
Resist tension
What is the most common type of collagen?
Type I collagen
Describe the structure of type I collagen
Fibrils are aligned and cross linked to increase tensile strength
Comprised of two collagen type alpha 1 chains and a collagen type alpha 2 chain secreted as procollagen that is processed and crosslinked at the cell surface
What gives collagen fibers their banding appearance on a scanning electron micrograph?
Their fibril arrangement
What is scurvy?
Cells must have sufficient levels of vitamin C in order to properly cross link collagen fibers (is a cofactor in collagen synthesis)
Vitamin C deficiency will weakened collagen and CT in the body causing scurvy
What are some sx of scurvy?
Loss of teeth, blood vessel rupture (easy bruising), and poor healing as maintenance requires continual collagen production
What is Ehlers-Danlos syndrome?
Abnormal collagen synthesis leading to weak collagen fibers (multiple forms) due to mutations in collagen genes or collagen synthesis genes
What is elastin?
Protein fibers that are elastic and recoil back to original state when stretched
They are an assembly of tropoelastin, fibulin 1 and fibrillin-1/2