Metabolism Flashcards
___ is the sum of chemical reactions in the body
metabolism
what are the 3 roles of metabolism?
- extract ATP from nutrients
- use the energy to do work
- store energy for future use
___ pathways synthesize larger molecules from smaller ones
anabolic
what pathway is dominant in the absorptive or fed state?
anabolic
___ pathways break larger molecules into smaller one s
catabolic
what pathway is dominant in the postabsorbative or fasted state?
catabolic
term for formation of glycogen
glycogenesis
term for formation of lipids
lipogenesis
term for formation of newly synthesized glucose
guconeogenesis
term for breakdown of glycogen
glycogenolysis
term for breakdown of lipids
lipolysis
what anabolic pathway is present in the postabsorbative state?
gluconeogenesis
what catabolic pathways are present in the postabsorbative state?
glycogenolysis, lipolysis
what anabolic pathways are present in the absorptive state?
glycogenesis, lipogenesis
what catabolic pathways are present in the absorptive state?
none
excess nutrients in the body are stored as ___ and ____
fat, glycogen
where in the body is glycogen stored?
liver, skeletal muscle
___ is a rapid source of energy in the body
glycogen
removing excess glucose from the plasma and storing it as glycogen helps do what?
lower plasma glucose in the absorptive state
is fat light or heavy?
light
____ energy is harder and slower to access
fat
what two things can make triglycerides?
glucose, excess amino acids
the formation of triglyceride from excess glucose helps do what?
lower plasma glucose in the absorptive state
what are the four locations of nutrients?
muscle, fat, liver, brain
is glucose acidic or basic?
acidic
what hormone takes glucose out of plasma?
insulin
what is known as the liver production of glucose?
gluconeogenesis
what processes does insulin inhibit?
gluconeogenesis, lipolysis
what is the term for fat release from adipocytes?
lipolysis
what cells of the pancreas secrete insulin?
beta
what is the most potent stimulus for insulin release?
increased plasma glucose levels
what hormones feedforward for insulin release?
incretins
insulin inhibits the activity of what system?
sympathetic
insulin stimulates the activity of what system?
sympathetic
increase in either plasma insulin or ___ ___ can stimulate release of insulin
amino acids
long term exposure to elevated plasma fatty acids can result in ____
atherosclerosis
muscle needs ___ ___ to replace the protein lost in the absorptive state
amino acids
___ ____ are needed in the tissue for cellular growth and repair
amino acids
what is the direct effect of the binding of insulin on muscle and fat cells?
insertion of glucose transporters in the plasma membrane
insulin stimulates the activity of what enzyme in liver tissue?
hexokinase
____ is the enzyme responsible for phosphorylating glucose upon entry into the cell
hexokinase
because hexokinase phosphorylates glucose, there is a ___ ___ for glucose to move into the cell
concentration gradient
in this tissue, glucose is either stored as glycogen or oxidized for ATP
muscle
in this tissue, glucose is either stored as glycogen or converted to triglyceride
liver
is triglyceride stored in the liver long term?
no
in this tissue, glucose is either oxidized for ATP or converted to triglyceride
fat
in this tissue, glucose is only oxidized for ATP
brain
where do triglycerides go after being made in the liver?
bloodstream to fat cells
in what three tissues do amino acids build new protein?
muscle, fat, brain
triglycerides made in the liver are exported to adipose tissue in what form?
very low density lipoprotein
in what two tissues does the conversion of glucose to fatty acids occur?
liver, fat
what are the intermediates in the conversion of glucose to fatty acids?
glycerol, 3 fatty acids
what occurs to make an amino acid a keto acid?
deamination
what is the byproduct of converting an amino acid into a keto acid?
NH3 (ammonia, toxic)
what is ammonia converted to in the liver to make it non-toxic?
urea
what does the keto acid get converted into?
glucose
long term storage of triglycerides come in what two forms?
chylomicrons, VLDLs
VLDLs and chylomicrons are balls of fat covered in what?
phospholipids
is a phospholipid a mono or bilayer?
mono
____ are the fats that come from the small intestine and carry fats that originated in the diet
CMs
___ fats deposit their triglycerides in the adipose tissue
CM
___ fats are taken up by the liver and their remaining triglyceride is repackaged in a VLDL
CM
____ fats are synthesized by the liver and contain triglyceride that was made from excess AA and glucose and triglyceride found in a CM remnant
VLDL
___ fats contain newly synthesized triglyceride and dietary triglycerides
VLDL
____ fats leave the liver and deposit their triglycerides in the adipose tissue for long term storage
VLDL
the ____ ___ is disassembled in the liver and cholesterol released from it turns into the VLDL
chylomicron remnant
type 1 diabetes is due to ___ ____
insulin deficiency
_______ is an autoimmune disease that destroys B cells
type 1 diabetes
type 2 diabetes is due to development of _____ _____
insulin resistance
if there is low glucose in the blood, it all goes to what tissue?
brain
can the brain run on ketone bodies?
yes
___ ___ is the switch that tissues make to oxidizing alternative fuel sources to make ATP so that only the brain is using glucose
glucose sparing
muscle and fat rely on __ ____ oxidization during glucose sparing
fatty acids
liver relies on ___ ____ oxidization during glucose sparing
amino acids
what two processes are stimulated by glucagon?
glycogenolysis, gluconeogenesis
glucagon stimulates ___ breakdown
muscle
glucagon stimulates ___ ___ release from fat tissue
fatty acid
what pancreas cells produce glucagon?
alpha
what is the major stimulator for glucagon release?
decrease in plasma glucose
is insulin needed during glucose sparing?
no
when glucose is low, fat tissues release ___ ___ and ____ into the plasma from triglyceride breakdown
fatty acids, glycerol
fatty acids in the liver are converted into __ ____ instead of ATP
ketone bodies
why does the liver produce ketone bodies instead of ATP from fatty acid oxidization?
liver has low levels of oxaloacetate
adipose tissue and muscle do not have access to glucose unless ___ is around
insulin
does elevated blood glucose cause vasoconstriction or vasodilation?
vasoconstriction
