Adipose and Muscle Flashcards
how is fat stored for a source of energy
lipid droplets of triglyceride
why are triglycerides a more optimal resource than protein and carbohydrates in a food deprivation event
they offer twice the number of calories and the body has a limited ability to store protein and carbohydrates
what two signaling mechanisms does fat have to regulate metabolism
paracrine and hormone signaling
what are the two types of adipose tissue
white (unilocular) and brown (multilocular) adipose tissue
what type of adipose tissue is more prominent in a fetus and infant
brown adipose tissue
what are the four main functions of white adipose tissue
energy storage
insulation
vital organ cushioning
secretions of hormones
from what cells are white adipose tissue derived
perivascular stem cell
from what cells are brown adipose tissue derived
skeletal myogenic progenitor cell
what does the term panniculus or abdominal pannus best describe
an apron of skin and fat that hangs down from the abdomen
what shape or fat distribution is attributed to higher health risks
apple shape or abdominal fat dominance
what is the preferential site for accumulation of adipose tissue for both sexes
mammary fat pad
what are some of the broad associated risks of increased internal organ fat
stroke
heart disease
cancer
phlebitis
gout
osteoarthritis
gynecologic abnormalities
gallbladder disease
liver disease
lung disease
what are adipokines
hormones, growth factors, or cytokines secreted by adipose cells
what five things do adipokines help to regulate
energy homeostasis
adipogenesis
steroid metabolism
angiogenesis
immune reponses
what hormone helps to inhibit food intake, stimulates metabolism, and the loss of body weight
leptin
what are the five major functions of leptin
regulates appetite and body energy expenditure
signals to the brain about body fat storage
increases formation of new vessels
involved in blood pressure control by regulating vascular tone
potent inhibitor of bone formation
an increase in leptin secretion resulting from obesity causes what three things to happen
non-adipose tissue becomes resistant to leptin
increased insulin resistance
increase in internal organ fat
what two physiologic factors control an individual’s weight
short term weight regulation (appetite and metabolism controlled on a daily basis)
long term weight regulation (appetite and metabolism control on a continual basis)
what are the two main hormones regulating adipose physiology
insulin and leptin
what are three secondary hormones or steroids that contribute to adipose physiology
thyroid homrone
glucocorticoids
hormones of the pituitary gland
what percentage of body fat is brown fat in a newborn
5%
what 3 things regulate and may alter the volume of brown fat
sympathetic nervous system
cold outdoor temperatures
physical activity
what is the name of the process of converting white fat to brown fat or transforming brown fat to white fat
transdifferentiation of adipose tissue
what two myofilaments are responsible for muscle contraction
actin and myosin 2
what term refers to the cytoplasm of striated muscle cells
sarcoplasm
what is the smallest functional unit of striated muscle tissue
sarcomere
what is the protein responsible for carrying oxygen in muscle tissue
myoglobin
what are the two primary classifications of muscle
striated and smooth muscle
what are the three subclassifications of striated muscle
skeletal muscle
visceral striated muscle
cardiac muscle
what are the three connective tissue layers of a muscle bundle from outer most layer surrounding the bundles of fasicles to the layer that surrounds an individual muscle fiber
epimysium
perimysium
endomysium
what three broad characteristics are important in considering the function of skeletal muscle fibers
speed of contration
enzymatic velocity
metabolic activity
what two components of muscle are most needed for optimal muscle performance
myoglobin to carry oxygen
ATP for energy
rhabdomyolysis can result in which type of damage to the kidneys
destruction of the renal epithelium resulting in acute renal failure as evident by dark “coca cola” urine
what color would you expect a fast twitching muscle fiber to be
white
what color would you expect a slow twitching muscle fiber to be
red
what type of muscle fiber would be expected to have a high oxygen content due to high levels of myoglobin, capillaries, and mitochondria
type 1
what type of muscle fiber has a fast twitch but fatigues easily
type 2b
what type of muscle fiber has a fast twitch but is resistant to fatigue
type 2a
what is the byproduct of anaerobic respiration as muscles are exhausted
lactic acid which is associated with pain in the muscle
what are the five most prominant microscopic features of skeletal muscle
long, cylindrical cells
multiple, peripheral nuclei
striations
sarcomere present
no cell-to-cell junction
what are the five most prominent microscopic features of cardiac muscle
short cylindrical cells
single central nuclei
striations
intercalated discs
sarcomere present
what are the five most prominent microscopic features of smooth muscle
small, elongated fusiform cells in sheets
single, central nuclei
do not display a striated pattern
gap junctions present
no sarcomere
the myoblast is derived from what cell lineage
multipotent myogenic stem cell
how do cardiac cells repair themsevles
they do not have a reparative mechanism and result in cell death that eventually results in scar tissue
how does skeletal muscle repair itself
by the activation of the myogenic stem cell called satellite cells
what muscle type continues to divide and maintain or increase in cell number
smooth muscle cells
