Chapter 9 - Adipose Tissue Flashcards
What are the two types of adipose tissue?
- White
- Brown
What causes the white space in slides of adipose tissue?
Formalin pulls the lipids away leaving a white space
Where are all the cytoplasmic contents located in adipose tissue?
They are pushed to the side
Are adipose tissue highly vascular or avascular?
Highly vascular
What is a cluster of adipose cells called?
Lobule
What are lobules (clusters of adipose cells) seperated by? Name and tissue type
Septa
Dense irregular CT
What type of fiber is located in intervening spaces between adipocytes?
Reticular fibers
What cells are adipocytes derived from?
Mesenchymal Stem Cells
What is the main cell type present in adipose tissue?
Adipocytes
What is the major function of adipose tissue?
Store excess energy
In what macromolecues is energy stored in adipocytes?
- Triglycerides within a lipid droplet
- Limited carbohydrates and protiens
What is the second minor function of adipocytes?
Are endocrine glands that regulate energy metabolism
What are some disease states that would be effected by our endocrine glads misreggulation of metabolism?
Heart disease, chronic inflammation, diabetes
What animal has a lot of adipose tissue?
Camel, the hump is made almost entriely of adipose tissue which can generate water through the breakdown of lipids
What causes lipogenesis? What does lipogenesis produce?
Excess nutrition (lipids and carbs) > lipogenesis > increased fat storage
Produces triglycerides
What causes lipid oxidation?
Insufficent nutrition > lipid oxidation > energy production
What differentiates brown and white adipose tissue? How many vacuoles? What organisms are they found in?
White; single large lipid vacuole = unilocular, adult humans
Brown; multilocular, more mitochondria and cytochrome C (?),fetal life and early childhood, hibernating animals
What important function does brown adipose tissue serve in babies?
Thermogenesis
What determines wether adipose tissue will be brown or white?
Transcription factors
What are the differnt cell stages form MSC to adipocyte?
MSC > early lipoblast > midstage lipoblast > latestage lipoblast > mature white adipocyte
MSC > early lipoblast > brown adipocyte
What specific transcription factors are requiered for differentiation to white adipocytes? (2)
- PPARy
- RXR
What specific TF are required to form a brown adipocyte?
- PRDM 16
- PGC-1
What signal do brown adipocytes never recieve?
The signal to merge vacuoles
What are in the cytoplasmic contents of adipocytes?
- Mitochondria
- Glycogen stores
- Basal Lamia - allows for meshwork and attachment between adjacent adipocytes
What is the subcutaneous layer? What is it important for?
Layer below the dermis
Important for insulation