Cell Division, Diversity and Organisation - Stem Cells Flashcards
define stem cells
undifferentiated cells that can undergo cell division and have the potential to differentiate
define totipotent
can differentiate into any type of cell e.g cells of a zygote
define pluripotent
can form all tissue types but not whole organisms e.g cells of an embryo
define multipotent
can form a range of cells within a certain type of tissue e.g bone marrow
define unipotent
can give rise to only one cell type e.g muscle cells
what is the role, lifespan and number produced from stem cell colonies in the bone marrow of erythrocytes
role: transport oxygen
lifespan: 120 days
number produced: 3 billion per kg of body mass per day
what is the role, lifespan and number produced from stem cell colonies in the bone marrow of neutrophils
role: immunity
lifespan: 6 hours
number produced: 1.6 billion per kg of body mass per hour (more during infection)
what are the sources of animal stem cells
- embryonic
- umbilical cords
- bone marrow
explain embryonic as a source of animal stem cells
- initially totipotent, pluripotent once a blastocyst
- ethical issues - a potential life is destroyed, embryo cannot give consent
explain umbilical cords as a source of animal stem cells
pluripotent, more easily available, can be stored
explain bone marrow as a source of animal stem cells
multipotent (operation painful and has some risks)
explain somatic cells as a source of animal stem cells
somatic cells may be artificially triggered into pluripotency (iPS)
what are the sources of plant stem cells
meristem tissue - pluripotent
what are the uses of stem cells
- used in research
- used to treat disease e.g Alzheimer’s and Parkinson’s
-study developmental biology - repair of damaged tissues
