Chapter 4- Book Flashcards
The restoration of tissue structure sand function after an injury
Tissue repair
Replacement of tissue with new tissue of same type
Regeneration
This type of tissue leads to fibrosis and scar formation
Connective tissue
The Body tissue and organs are composed of two types of tissue:
Parenchymal
And
Stromal
Actual cells of each organ (tissue type)
Ex: liver cells
Parenchymal
Supporting connective tissues, blood vessels, fibroblasts, nerve fibers, and extracellular matrix.
(Ex: anything in the heart that isn’t a cardiac muscle cell)
Stromal tissue
The process of increasing the # of cells of an organ or body part
Proliferation
process where a cell becomes more specialized in terms of structure and function
Cell differentiation (specialization)
Undifferentiated cells that are capable of producing many types of different cells
Stem cells
Proliferation of cells is drive by ___________
Growth factor
All different cell types in the body originate from this cell
Fertilized ovum
As a cell becomes more ______, the stimulus to induce mitosis becomes more ______
Specialized, limited.
What are the cell cycle phases (4)
G1, S, G2, M
What happens in the G1 phase of the cell cycle?
Post mitotic phase.
DNA replication stops while RNA, protein synthesis and cell growth takes place.
Increase in organelles and cytoskeletal elements in prep for DNA replication in next phase
What happens in the S phase of the cell cycle?
DNA replication, creates two separate sets of chromosomes
Each set has a ‘daughter’ chromosome that remains the stem cell (unchaged and continues to replicate)
What happens in the G2 phase of cell cycle?
DNA replication stops.
RNA and protein synthesis continues …. called the PREMITOTIC phase
Enzymes and other proteins needed for cell division are synthesized and moved to their proper sites
What happens in the M phase of cell cycle?
Nuclear divisions and mitosis occurs. Formation of mitotic spindles and cell division happens.
What is the G0 phase of the cell cycle?
When the cells exit the normal cell cycle phase and become more specialized. They can re-enter the cell cycle though under intense conditions, however a lot fo specialized cells don’t.
EX: Neurons
Proteins that control the entry and progression of cells through the cell cycle
Cyclins
Cyclins bind to a protein called:
Cyclin- dependent Kinases (CDKs)
Enzymes that phosphorylate proteins
Phorphylate means to add a phosphorous. Important in changing ADP to ATP
Kinases
Body tissues are divided into 3 different types of tissues based on their ability to regenerate
What are they?
- ) continuously dividing
- ) stable
- ) permanent tissue
When stem cells divide what happens?
1 daughter cell retains the stem cell characteristics, the other daughter cell becomes the progenitor cells and undergoes the process that leads to terminal differentiation
What are the 3 specific properties of stem cells?
- ) self-renewal- can undergo numerous mitotic divisions while maintaining undifferentiated state
- ) asymmetric replication- mitosis creates: 1 daughter cell and 1 cell that changes
- ) differential potential- potency of the cell to change state
2 types of stem cells
- ) embryonic stem cells
2. ) adult stem cells
A pluripotent cell that comes from teh mass of the blastocyst stage of the embryo
- can generate many cell types
Embryonic stem cell
Can generate multiple lineages of cells and are present in the bone marrow and several other tissue
Adult stem cells
Small proteins that increase cell size and cell division
Growth factor
Growth factor is produced by ____ and activated at the ___ of ____
Leukocytes
Site of injury
Functions of growth factor (3)
- ) promote cell proliferation
- ) prevent apoptosis
- ) enhance synthesis of cellular proteins in preparation for mitosis
2 types of growth factor that are extremely important in healing tissues
- ) VEGF- stimulate proliferation of cells. Initiates capillary sprouting in repair
- ) FGF-2: Angiogenesis mainly by stimulating the proliferation of endothelial cells
Extracellular matrix (ECM) has 3 basic components, what are they?
- ) Fibrous structural proteins
- ) Water-hydrated gels
- ) adhesive glycoproteins
There are two types of ECM, what are they?
Basement membrane- surrounds epithelial, endothelial, and smooth muscle cells
Interstitial matrix- present in spaces between cells in connective tissues and between the epithelium and supporting cells of the blood vessels
With the ______ in ECM, the cells will not be able to proliferate. It will in a haphazard way, resulting in nonfunctional tissues
Basement membrane
The healing process has a primary objective: _____
To fill the gap created by tissue destruction and to restore the structural continuity of the injured part.
Restoration of the injured tissue to its normal structure and function by proliferation of adjacent surviving cells.
Tissue regeneration
Extensive deposition of collagen that occurs in organs that are incapable of regeneration
Fibrosis
Phases of tissue repair (3)
- ) hemostasis, angiogenesis, ingrowth of granulation tissue
- ) emigration of fibroblasts and deposition of extracellular matrix
- ) maturation and reorganization of the fibrous tissue (remodeling)
