Adipose Tissue Flashcards
What is the function of adipose tissue ?
1- source of energy
2- heat insulation
3- mechanical cushion
What is the endocrine function of the adipose tissue ?
To produce hormones such as leptin, resistin and cytokine TNFa
What determines the being overweight or obese ?
The amount of body fat / adipose tissue
What is the WHO definition of overweight and obese ?
Abnormal or excessive fat accumulation that presents a risk to health
Why is fat is an efficient way to store excess energy ?
1- it is stored with very little water
2- more energy can be derived per gram of fat
3- fat gives much more energy than carbohydrates
4- if animals stored their excess energy as carbohydrate as the increased mass would interfere with mobility.
What are the two types of adipose tissue ?
1- white adipose tissue (WAT)
2- brown adipose tissue (BAT)
Who has WAT and who has BAT ?
WAT in adults and BAT is in newborns
Why gives BAT its color ?
Smaller lipid droplets, the cells rich vascularization and gives a densely packed mitochondria giving it its color.
What dose the WAT contain ?
It contains white adipocytes, a single large lipid droplet and a few mitochondria.
What dose the WAT secret ?
It secretes adipose derived hormones that regulate insulin sensitivity .
What dose BAT contain ?
It contains brown adipocytes containing multiple small lipid droplets rich in mitochondria
Why is BAT important in hibernating animals ?
It is important for regulating body temperature via non-shivering thermogenesis.
What is the function of uncoupling protein-1 (thermogenin) ?
It is a specific transmembrane carrier in the inner mitochondrial membrane of BAT uncouples mitochondrial fatty acid oxidation and ATP production.
What dose uncoupling of proton flow from ATP synthesis allow ?
It allows the energy stored in the proton gradient to be dissipated as heat.
What is the function of thermogenin ?
Thermogenin (UCP-1) is a natural uncoupler of oxidative phosphorylation
