CHAPTER 6: ADIPOSE TISSUE Flashcards
Connective tissue in which fat-storing cells or adipocytes.
typically found isolated or in small groups within loose or dense irregular connective tissue
Adipose Tissue
normally represents 15%-20% of the body weight in men, somewhat more in women.
Adipose Tissue
serving as storage depots for neutral fats, chiefly triglycerides (long-chain fatty acyl esters of glycerol), adipocytes function as key regulators of the body’s overall energy metabolism.
Adipose Tissue
(long-chain fatty acyl esters of glycerol)
triglycerides
specialize in concentrating triglycerides as lipid droplet(s), with other cells normally accumulating relatively little lipid.
Adipocytes
active cells metabolically, responding to both nervous and hormonal stimuli. They release hormones and various other important substances.
Adipocytes
Dominate connective tissue o found isolated or in small groups within loose or dense irregular connective tissue o active cells metabolically, responding to both nervous and hormonal stimuli. o release hormones and various other important substances and adipose tissue is now recognized as an endocrine organ at the center of nutritional homeostasis.
Adipocytes
2 TYPES OF TISSUE
White Adipose Tissue
Brown Adipose Tissue
common type specialized for fat storage, consists of cells each containing one large cytoplasmic droplet of whitish-yellow fat.
White Adipose Tissue
contains cells with multiple lipid droplets interspersed among abundant mitochondria, which helps give this tissue a darker appearance.
Brown adipose tissue
release heat and function to warm the blood.
Brown adipose tissue
Specialized for relatively long-term energy storage, adipocytes of white adipose tissue are spherical when isolated but are polyhedral when closely packed in situ.
WHITE ADIPOSE TISSUE
When completely developed, a white adipocyte is very large, between 50 and 150 μm in diameter, and contains a single huge droplet of lipid filling almost the entire cell.
WHITE ADIPOSE TISSUE
the single large droplet of triglycerides, white adipocytes are also called unilocular
White Adipocytes
the lipid is removed from cells by _____
XYLENE
adipocytes are often empty in standard light microscopy
UNILOCULAR
have a signet-ring appearance, with the lipid droplet displacing and flattening the nucleus against the cell membrane
White Adipocytes
produces hormone called _____ or “satiety factor” with target cells in the hypothalamus, o can store triglycerides
LEPTIN
triglycerides derived from three sources:
- Dietary fats brought to the cells via the circulation as chylomicrons
- Lipids synthesized in the liver and transported in blood with very low-density lipoproteins (VLDLs)
- Free fatty acids and glycerol synthesized by the adipocytes.
generate benign tumors called lipomas that are relatively common, although malignant adipose tumors (liposarcomas) occur infrequently. Fetal lipomas of brown fat are sometimes called hibernomas.
Unilocar Adipocytes
generate benign tumors called ____
lipomas
malignant adipose tumors
liposarcomas
Fetal lipomas of brown fat are sometimes called ___
HIBERNOMAS
Most _________ in a white adipocyte are near the peripheral nucleus, including mitochondria, a small Golgi apparatus, a few cisternae of RER, and free polyribosomes.
cytoplasmic organelles
peripheral nucleus, including ______
mitochondria, a small Golgi apparatus
The thin, submembranous layer of cytoplasm surrounding the lipid droplet contains ________________
cisternae of smooth ER (SER) and pinocytotic vesicles.
form a fine interwoven network that supports individual fat cells and binds them together
Reticular fibers
between adipocytes may not always be apparent in tissue sections.
microvasculature
The distribution of _____________ changes significantly through childhood and adult life and is partly regulated by sex hormones controlling adipose deposition in the breasts and thighs.
white adipose tissue
( (Gr. chylos, juice + micros, small)
are particles of variable size, up to 1200 nm in diameter.
Chylomicrons