Misouras - Fed State, Fasting and Starvation Flashcards Preview

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Flashcards in Misouras - Fed State, Fasting and Starvation Deck (57):
1

what is the time period for the fed state (post-prandial state)

0-4 hours after eating

2

what is the fasting state

more than 4 hours after eating

3

what is the starving state

more than 3 days without food

4

what are the 2 metabolic pathways

catabolic and anabolic

5

what happens in each of the metabolic pathways

catabolic = energy production
anabolic = meets demand for biosynthesis of macromolecules

6

what occurs in the fed/absorptive state

digestion, absorption, transportation and distribution of dietary nutrients (thermic effect of food) - both catabolic and anabolic

7

what metabolic pathway occurs in the fasting state

catabolic pathway

8

what metabolic pathway occurs in the starvation state

catabolic pathway

9

what is the goal of metabolism

adequate energy to satisfy requirements of organism/homeostasis

10

what are the 5 main "organs or targets" for nutrients

adipose, brain, muscles, liver and RBCs

11

what are the sources of metabolic fuels in the fed state

dietary intake (carbohydrates, proteins, fats)

12

what are the sources of metabolic fuels in the fasting state

glycogen stored in liver

13

what are the sources of metabolic fuels in the starvation state

fat (fatty acids) stored in adipose tissue

14

what source of metabolic fuel do the RBCs utilize

only glucose

15

what source of metabolic fuel does the brain utilize

mainly glucose and then ketone bodies

16

what source of metabolic fuel does the liver utilize

first glucose and then fatty acids

17

what source of metabolic fuel do the muscles utilize

first glucose (only during excersie) and then fatty acids and ketone bodies

18

what source of metabolic fuel do the adipose cells utilize

first glucose and then fatty acids

19

what is the first choice of fuel for all organs

glucose

20

which organ needs a constant supply of glucose

the RBCs

21

what is the source of glucose in the fed state

from dietary carbohydrates - glucose is abundant

22

what is the source of glucose in the fasting state

1. glycogen stores (primary source)
2. glucose from new synthesis

23

what is the source of glucose in the starving state

only from new synthesis

24

what do normal blood glucose levels need to be for RBCs and the brain to function properly

70-100 mg/dL

25

what is the active pathway for glucose for the brain and what does insulin stimulate in the fed state

glycolysis (ATP from glucose) and no effect from insulin

26

what is the active pathway for glucose for the RBCs and what does insulin stimulate in the fed state

glycolysis (ATP from glucose) and no effect from insulin

27

what is the active pathway for glucose for the liver and what does insulin stimulate in the fed state

glycolysis, glucogenesis, and fatty acid synthesis - insulin stimulates all of these pathways

28

what is the active pathway for glucose for adipose and what does insulin stimulate in the fed state

glycolysis and lipogenesis (storage of fatty acids) - insulin stimulates glucose transport into cells and lipogenesis

29

what is the active pathway for glucose for the muscles and what does insulin stimulate in the FED STATE

glycolysis, glycogenesis, and protein synthesis
insulin stimulates: glucose & amino acid transport into cells, glycogenesis & protein synthesis

30

when are glucose levels returned to basal level and what signals the fasting state

4 hours after a meal and glucagon is secreted by pancreas to signal fasting state

31

how are the blood glucose levels maintained during the fasting state

mobilization of stores (glycogenolysis) and synthesis of glucose from non-sugar precursors (gluconeogenesis)

32

what generates fatty acids to be used as energy in muscle, liver and other tissues

lipolysis in adipose tissue

33

what are converted to ketone bodies in the liver

fatty acids

34

what are ketone bodies used for

as an energy source by muscle and other tissues in low blood glucose situations

35

what maintains blood glucose during starvation

gluconeogenesis in the liver

36

what organs still use glucose sources during starvation

brain and RBCs (brain can adapt to use ketone bodies as well)

37

what happens in the liver during starvation

increased ketogenesis to support energy needs of the brain

38

what do adipose, muscle, and liver use for fuel during starvation

fatty acids - saving the ketone bodies for the brain and the remaining glucose for RBCs

39

when are ketone bodies used for metabolic fuel and what pathway creates them

used by muscle and brain when there is no glucose - broken down into amino acids by ketolysis and enter various oxidation pathways to create ATP

40

what are the insulin and glucagon levels like in the fed state and what pathways do they regulate

insulin is abundant- glucagon is low; high blood glucose after a meal. Regulate glycogenesis and glycolysis

41

what are the insulin and glucagon levels like in the fasting/starvation states and what pathways do they regulate

glucagon is abundant - low blood glucose and it stimulates catabolic processes

42

what is the signal of metabolic stress (low levels of glucose)

glucagon

43

what is the primary stimulation of lipolysis (adipose)

epinephrine- glucagon plays a lesser role

44

what are the active pathway and glucagon effects in the brain during the fasting state

glycolysis (glucose) and ketolysis (ketone bodies) - no effect from glucagon

45

what are the active pathway and glucagon effects in the RBCs during the fasting state

glycolysis (glucose) - no effect from glucagon

46

what are the active pathway and glucagon effects in the liver during the fasting state

ketogenesis (fatty acids), gluconeogenesis, glycogenolysis, and beta-oxidation (fatty acids) - glucagon stimulates gluconeogenesis and glycogenolysis

47

what are the active pathway and glucagon effects in the adipose during the fasting state

lipolysis (fatty acids) and beta-oxidation (fatty acids) - glucagon stimulates lipolysis

48

what are the active pathway and glucagon effects in the muscles during the fasting state

beta-oxidation (fatty acids), ketolysis (ketone bodies) and protein degredation - no effect from glucagon

49

what is the difference between fasting and starvation

fasting has glycogenolysis and gluconeogenesis in liver and starvation only has gluconeogenesis as source

50

what happens to glucose levels in diabetes mellitus

there is an absence of endrogenous insulin or defective insulin signaling and the fed state is interpreted as fasting/starvation --> glucose levels stay HIGH

51

what is hypoglycemia

when blood glucose is below 40 mg/dL --> insufficient glucose for brain

52

what are 4 causes of hypoglycemia

fasting, neonatal, insulin-induced (opposite of diabetes) and alcohol-induced

53

what is fasting hypoglycemia

reduced glucose production by liver: hepatocellular damage or fasting individuals consuming lots of alcohol

54

what is neonatal hypoglycemia

newborns with metabolic defects or a diabetic mother can cause brain damage

55

what is insulin-induced hypoglycemia

abnormal insulin levels: diabetics on insulin or patients with insulinomas (insulin tumors)

56

what is alcohol- induced hypoglycemia

excessive alcohol intake impairs gluconeogenesis - worse in people with depleted glycogen stores

57

what are some complications of high glucose levels

macro and microvascular complications that can lead to cardiovascular disease, nephropathy and retinopathy