Adipose Tissue Flashcards
What types of cells predominate in adipose tissue?
Adipocytes
__________________ are large cells found isolated or in small groups and clusters within loose or dense irregular connective tissue
Adipocytes
Adipose tissue has five major functions. What are thehy?
- Metabolic regulation
- Energy storage (triglycerides)
- Insulation
- Endocrine (appetitie, immune regulation)
- Autocrine/paracrine (immune system, lipogenesis/lipolysis)
____________________ tissue conducts heat poorly but provides thermal insulation, fills the space between other tissues, and shapes and cushions regions of the body exposed to mechanical stress
Adipose
Excess fat is stored in ________________, which expand in size until the fat is used for fuel
Lipocytes
What do we mean when we say that adipocytes are active cells?
That they have metabolic functions; they respond to both nervous and hormonal stimuli, and they even release hormones
____________________ is a hormone produced more in subcutaneous fat while ______________ is a signaling molecule produced more in visceral fat
Leptin
IL-6
Adipose tissue stores ________________________, the largest repository of energy in the body
Triglycerides
Other than in the form of triglycerides, how else does the body store energy?
Glycogen
There are two types of adipose tissue that differ in their location, structure, color, and pathology. What are these two types?
White adipose tissue
Brown adipose tissue
Which type of adipose tissue is most common: white or brown?
White
_____________________ adipose tissue have cells that contain one large central droplet of whitish-yellowish fat in their cytoplasm
White
Where does white adipose tissue tend to be found in the body?
Visceral fat pads and subcutaneous fat pads
_____________________ adipose cells have multiple lipid droplets interspersed among abundant mitochondria, which gives this tissue type its distinctive color
Brown
In ________________________ cells are spherical when isolated and polyhderal when closely packed together; cells contain one huge lipid droplit that makes up 85% of its cellular weight
White adipose tissue
White adipocytes are ____________________, meaning that their triglycerides are stored in a single locus
Unilocular
Is white adipose tissue vascularized?
Yes
White adipose tissue is subdivided into incomplete ______________________ by a partition of ___________________________
Lobules
Connective tissue
Fat cells or ______________________ make up fat __________________, which make up fat pearls that constitute fat sections
Adipocytes
Fat lobules
______________________ fibers form a fine interwoven network that support individual fat cells and bind them together
Reticular
A unilocular adipocyte appears as a thin ring of cytoplasm around an empty vacuole, sometimes referred to as the _____________________
Signet ring cell
How do nuclei appear in adipocytes?
Falttened because the large lipid droplet pushes nuclei to the side
What type of fixative stains lipids black?
Osmium tetroxide
What cells are the sole source of the hormone leptin?
Adipocytes
Leptin is also known as the ____________________________ because it regulates appetite and participates in regulating the amount of adipose tissue
Satiety factor
White adipose tissue differentiates from embryonic mesenchymal cells as _____________________
Lipoblasts
Early ___________________ have the appearance of fibroblasts but are able to accumulate ____________ in their cytoplasm
Lipoblasts
Fat
In lipoblasts, lipid accumulations are isolated from one another at first but soon fuse to form the single large droplet characteristic of _______________________ adipocyte tissue cells
Unilocular
What gives brown adipose tissue its color?
Numerous mitochondria
Besides numerous mitochondria, what else gives brown adipose tissue its color?
Large number of blood capillaries
Brown adipocytes are polygonal and generally _________________ that cells of white adipose tissue, and their cytoplasm contain great number of lipid droplets of various sizes, making them _______________________
Smaller
Multilocular
What is the principle function of brown adipose tissue?
Heat production
How does brown adipose tissue resemble an endocrine gland?
Cells assume an epithelial-like arrangement closely associated with blood capillaries
Brown adipose tissue is subdivided into partitions of connective tissue ____________________ that are better delineated than those of white adipose tissue
Lobules
Do brown adipose tissue cells receive direct sympathethic innervation?
Yes
Nuclei in brown adipose tissue tend to be _____________________ and centrally located
Spherical
The main function of multilocular adipose tissues is to ___________________ by nonshivering ___________________, the physiology of which is best understood in the study of hibernating species
Produce heat
Thermogenesis
Which emerges first during fetal development - white or brown adipose tissue?
Brown
In humans, the amount of brown fat is maximal relative to body weight at ________________ when nonshivering thermogenesis is most needed
Birth
Brown adipose tissue largely disappears by ________________________ or is replaced by white fat during childhood
Involution
Where can brown adipose tissue be found in adults?
Kidneys
Adrenal glands
Aorta
Mediastinum
