Radiobiology part 2 Flashcards
How are cells of a system tissue categorised
the rate of proliferation, and stage of development
who discovered radiosenstivity is a function of the metabolic state of the tissue being irradiated.
Bergonie and tribondeau
What are the four laws of bergonie and tribondeau
- Stem cells are radiosensitive, the more mature the cell the more resistant.
- Younger tissues and organs are more sensitive than mature cells
- When metabolic activity is high radio sensitivity is high
- As the proliferation rate for cells and growth rate for tissues increases the radiosensitivity also increases
What is the radiosensitivity of organs is determined by
- function of organ in the body
- Rate at which cells mature and turn over in the organ
- Inherent radiosensitivity of cell type
What is a differentiated cell
specialised functionality or morphologically, is a mature cell, or the end in a cell population
What is an undifferentiated cell
an immature cell whose primary function is to divide. These are considered stem cells, or precursor cells in a population.
What is an example of a differentiated cell
Spermatoza
What is an example of a undifferentiated cell
Spermatagonia
What are the three cell categories
stem cells
transit cells
static cells
What are stem cells
Undifferentiated immature cells which retain the ability to divide throughout their whole life, they also contribute to the bodies ability to renew and re[air its tissues.
What are stem cells (examples)
Bone marrow, epidermis of skin
What are transit cells
cells that are moving from a stem cell to an end cell compartment
What are transit cells (example of one that divides in transit and one that does not divide)
Nucleated red cell
Reticulocyte in bone marrow
What are Static cells
Fully differentiated and exhibit little to no mitotic activity
What are Static cells (example)
Nervous tissue, muscle
