exam 1 Flashcards
Capable of dividing and renewing themselves for long periods
• Unspecialized
• Generate daughter cells that can differentiate into many specialized cells
• Exist in embryos & adult tissues
stem cells
Potential of a single cell to develop into an entire organism
totipotent
• Ability to develop into all cell types of the body, but not supporting structures (placenta, amnion, etc.)
pluripotent
Ability to give rise to a small number of different cell types
multioitent
• Capacity to give rise to a single cell type
Unipotent
Found in early embryos
Able to differentiate into MANY cell types = plasticity
pluripotent stem cell
Blood cells: red blood cells, B lymphocytes, T lymphocytes, natural killer cells, neutrophils, basophils, eosinophils, monocytes, macrophages, platelets
hematopathic stem cells
Epidermis, keratinocytes, hair follicles
skin stem cells
Neurons, astrocytes, oligodendrocytes
neural stem cells
Digestive tract lining: absorptive cells, goblet cells, Paneth cells, enteroendocrine cells
epithelial stem cells
- Originally found in bone marrow
- Also located in adipose tissue, nervous system, skin, tendon, ligaments, synovial membranes, muscle, trabecular bone
- Give rise to osteoblasts, chondrocytes, adipocytes & other connective tissue
Multipotent Stem Cells (Adult)
Able to differentiate into 1 type of cell
Ex. Hepatoblasts can differentiate to hepatocytes of
the liver
unipotent
intermediate cells
Progenitors
Daughter cells from same replication have different fates
asymmetric cell division
dysregulation of ________ cell division lead to cancer
asymmetric
Microenvironment that controls stem cell self-renewal Prevents stem cells from becoming depleted or
overproduced
Controlled by extrinsic & intrinsic signaling
Including nutrients and growth factors in the fluid surrounding the cell
stem cell niche
Use of stem cells to treat the following conditions
Parkinson’s disease, Type 1 diabetes, Alzheimer’s disease, stroke, spinal cord injury, burns, heart disease, osteoarthritis, rheumatoid arthritis
• What are proteoglycans made of?
GAG’s (mucopolysaccharides) and proteins
negative charged sugars
Also called mucopolysaccharides
Chondroitin sulfate, keratan sulfate, heparan sulfate
GAG’s (mucopolysaccharides)
• What impact does the negative structure of GAGs have on its function?
because of its negative structure of GAG’s water floods into the matrix containing GAG’s and creates a swelling pressure
What is the difference between a proteoglycan monomer and aggregate?
Monomers give bottle brush appearance
GAGs repel each other
Aggregate is many monomers attached to hyaluronic acid
Aggregate attached to cell surface
Where are proteoglycans located in the body?
They are found in all connective tissues, extracellular matrix (ECM) and on the surfaces of many cell types.
How is collagen assembled (in general)?
three helical polypeptide a chains of amino acids that wind around one another forming a collagen triple helix
How would collagen be organized in bone vs tendons?
collagen provides strengh and support for bones and tendons