Chapter 21: Regulation of Metabolism & Growth Flashcards
What is metabolism, its 2 forms and examples of each?
Sum total of all cellular activities in the body
-
Anabolism: energy storage, tissue building
- Insulin, Sex steroids, Growth Hormone, Thyroxine
-
Catabolism: liberation of energy, tissue/substrate breakdown
- Glucagon, epinephrine, glucocorticoids, Growth Hormone, Thyroxine
3 biomolecules
Carbohydrates, proteins, lipids
Label the biomolecular pathway:


Label the biomolecular pathway:
How are lipids transported to cells?
In the blood
lipoprotein particles that transfer dietary lipids?
structure they come from and where are they delivered?
chylomicrons
GI Tract –> Liver, adipose tissue & other cells
type of lipoprotein that allows lipid transfer from liver –> body cells
Very-low density lipoprotein (VLDL)
where is the lipoprotein lipase located?
inner surface of capillaries
2 components of Triglycerides
Monoglyceride & 2 Fatty Acids
What mechanism allows FAs to enter the cell?
Diffusion
Where do Monoglycerides go for further metabolism?
Liver
Summary of Biomolecules:


What is the distribution of energy?
2 components of energy (include %’s)
Energy Input = Energy Output
Heat (60%) + Work (40%)
3 forms of work
Mechanical, Chemical, Transport
system that regulates the energy balance
Endocrine System


energy expended per unit time
Metabolic Rate
rate of energy expenditure of a person awake, resting, lying down & fasted for 12 hours
Basal Metabolic Rate (BMR)
What does BMS represent?
Effect with increasing activity?
minimum energy expenditure necessary to maintain body functions; increases with increasing activity
Is energy balance continuous?
Frequency of energy input?
No
Energy input is intermittent
Absorptive State
3-4 hours following a meal; nutrients in the bloodstream are plentiful from absorption
Postabsorptive State
between meals; energy stores must be mobilized
Absorptive State:
- Energy input >/< output as nutrients are absorbed
- Primary energy source for cell?
- What happens to excess nutrients taken up?
Absorptive State:
- Energy input > output as nutrients are absorbed
- Primary energy source for cell = glucose
- Excess nutrients taken up will be stored
In the absorptive state, the where is glycogen and triglycerides stored?
Glycogen Storage = Liver and Muscle
Triglyceride Storage = Adipose Tissue
Postabsorptive State:
- Energy input >/ output?
- Where does glucose go and why?
- What occurs with stored nutrients?
Postabsorptive State:
- Energy input output?
- Glucose is spared for the nervous system as other tissues use FAs or other sources for energy
- Stored nutrients are broken down and mobilized
Absorptive State Reaction:
3 Physiological responses in the blood after the absroption of small nutrients?

Absorptive State Reactions:
Where will glucose be distributed/in what forms?
Glucose Distribution in Absorptive State Reactions
- Most body cells –> CO2 + H2O + energy
- Liver & Muscle as glycogen
- Liver and adipose tissue as triglycerides (glycerol & FAs)
Absorptive State Reactions:
Where will FAs be distributed/in what forms?
After absorption of small nutrients in the blood, FAs will be distributed to the liver and adipose tissues as triglycerides (Glycerol and FAs)
Absorptive State Reactions:
Where will Amino Acids be distributed/in what forms?
Amino Acid Distribution in Absorptive State Reactions:
- Liver as FAs
- Muscle & other cells as proteins
Amount of glycogen storage in the liver and muscles
500g
Amount of triglyceride stored in adipose tissue
unlimited
In the Postabsorptive state, what is the initial stimulus and location of physiological responses (6)?
In the postabsorptive state, macromolecules are stored in the
- Muscles and other cells
- Adipose Tissue
- Liver
- Blood
- Nervous & Non-Nervous Tissue
Postabsorptive State Reaction:
When stored molecules get distributed into muscle and other cells, what is the form of its physiological response?
Result?
Postabsorptive State Reaction:
Physiological Response: Proteins –> AA
Result: AA in the blood and increase in CO2 + NH3 + H2O + energy in non-nervous tissue
Postabsorptive State Reaction:
When stored molecules get distributed into Adipose Tissue, what is the initial physiological response?
Resulting response?
Postabsorptive State Reaction:
Physiological Response: Triglycerides (FAs & glycerol)
Resulting Response: Increased FAs in the blood, Ketones in the liver & blood, and increase in CO2 + NH3 + H2O + energy in non-nervous tissue
Postabsorptive State Reaction:
When stored molecules get distributed into the Liver, what is the physiological and resulting response?
Postabsorptive State Reaction:
Physiological Response: Glycogen –> Glucose
Result: increased glucose in the blood & increased CO2 + H2O + energy in nervous tissue
Postabsorptive State Reaction:
When stored molecules get distributed into the Muscle, what is the physiological and resulting response?
Postabsorptive State Reaction:
Physiological response: Glycogen –> lactate & pyruvate
Resulting Response: glucose in the liver, increased glucose in the blood, and increased CO2 + H2O + energy in nervous tissue
General role of insulin in metabolism
absorptive state
General role of glucagon in metabolism
Postabsorptive state
How does insulin and glucagon stabilize blood glucose levels?
Negative feedback control


- Insulin secretion increases during _________ state
- What increases in plasma?
- Nervous system involved?
- Peptide involved?
- Insulin secretion increases during absorptive state
- Glucose & [AA] increases in plasma
- Parasympathetic NS
- Glucose-dependent insulinotropic peptide (GIP)
- Insulin secretion decreases during ________ state
- NS involved?
- Hormone involved?
- Insulin secretion decreases during postabsorptive state
- Sympathetic NS
- Epinephrine
Actions of insulin:
Increased insulin secretion in beta cells in the pancreas affect what body systems (4)?
Actions of insulin:
Increased insulin secretion in beta cells in the pancreas affect
- Most tissues
- Adipose tissue
- Liver & Muscle
- Muscle
Affect of increased insulin secretion in most tissues?
- Increased glucose uptake (except brain, liver, exercising muscle)
- Increased AA uptake
- Increased protein synthesis
- Decreased protein breakdown
Affects of increased insulin secretion in Adipose Tissue:
- Increased FA & triglyceride synthesis
- Decreased lipolysis
Affects of increased insulin secretion in liver and muscle:
- Increased glycogen synthesis
- Decreased glycogenolysis
Affects of increased insulin secretion in the liver:
- Increased FA & triglyceride synthesis
- Decreased gluconeogenesis
Glucagon:


Glucagon Secretion increases during __________ state.
NS?
Hormone?
Glucagon Secretion increases during postabsorptive state.
Sympathetic NS
Epinephrine
Glucagon secretion decreases during ________ state.
What increases in the plasma?
Glucagon secretion decreases during absorptive state.
Glucose increases in the plasma
Increased glucagon in alpha cells in the pancreas affect what systems (2)?
Liver & Adipose tissue
Affects of increased glucagon secretion in the liver:
- Increased glycogenolysis
- Decreased glycogen synthesis
- Increased gluconeogenesis
- Increased Ketone synthesis
- Increased protein breakdown
- Decreased protein synthesis
Affects of increased glucagon secretion in adipose tissue:
- Increased lipolysis
- Decreased triglyceride synthesis
Regulation of blood glucose levels:
Normal:
Hyperglycemia:
Hypoglycemia:
Regulation of blood glucose levels:
Normal: 70-100 mg/dL
Hyperglycemia: glucose > 140 mg/dL
Hypoglycemia: glucose < 60 mg/dL
What maintains blood glucose levels?
The actions of insulin and glucagon
Glucose Regulation via Insulin:
What increases insulin secretion in beta cells in the pancreas?
Glucose Regulation via Insulin:
Increased plasma glucose
Glucose Regulation via Insulin:
Affect what body systems (3)?
Glucose Regulation via Insulin:
Affects Most tissues, liver & muscle, liver
The affects of glucose regulation via insulin in most tissues:
Increased glucose uptake into cells
The affects of glucose regulation via insulin in the liver and muscle:
- Increased glycogen synthesis
- Decreased Glycogenolysis
Affects of glucose regualtion via insulin in the liver:
Decreased gluconeogenesis
Final result of glucose regulation via insulin?
Decreased plasma glucose and negative feedback
Glucose Regulation via Glucagon:
Effect of decreased plasma glucose on glucagon secretion in alpha cells in the pancreas?
Glucose Regulation via Glucagon:
Decreased plasma glucose increases glucagon secretion in alpha cells in the pancreas
Glucose Regulation via Glucagon:
Affects what 2 body systems?
Glucose Regulation via Glucagon:
Affects the liver and adipose tissue
Affects of Glucose Regulation via Glucagon in the liver:
Increased gluconeogenesis and glycogenolysis = increased plasma glucose, forming negative feedback
Affects of glucose regualtion via insulin in adipose tissue and the final result:
Increased lipolysis in adipose tissue –> increased plasma FAs to result in the spread of glucose
Characteristics of high protein, low carbohydrate diet/meal
Increased blood AA
Affects of increased blood AA on insulin and glucagon?
Increased insulin and gucagon
Subsequent steps for increased blood AAs and the increase in insulin release?
increases in AA uptake and glucose uptake (dangerous if carb intake is low)
Increased blood AA results in increased glucagon release resulting in?
Seemingly counterproductivity
low carb diet = low blood glucose
More glucagon stimulated by AAs; counteracts insulin effect to serve to maintain proper blood glucose levels
condition of impaired energy metabolism due to insulin deficiency or deficient insulin response
Diabetus Mellitus
primary sign of diabetus mellitus
major type of each?
hyperglycemia
Type 1: Early childhood, insulin production
Type 2: Later in life, insulin response
sigmoidal shaped curve that encompasses the the postnatal and pubertal growth spurts labeled by the percentage of total growth & age of individuals

2 step processes of growth?
List
-
Stimulators
- GH, Somatomedins (insulin-like Growth factors), Insulin, Thyroid hormones, sex hormones
-
Growth
- # of cells, size of some cells, bone length/thickness
Actions of Growth Hormone (GH):
What major structure controls the actions of GH?
Hypothalamus
Actions of Growth Hormone (GH):
Initial stimuli in the hypothalamus activates what response and where?
Actions of Growth Hormone (GH):
Initial increase in GHRH and decrease in GHIH (somatostatin secretion) activates increased GH secretion in the Anterior Pituitary
Actions of Growth Hormone (GH):
What activates the short loop negative feedback and to where?
Increased GH secretion in the anterior pituitary stimulates a short loop negative feedback to the Hypothalamus.
Actions of Growth Hormone (GH):
Increased GH secretion activates what 4 structures?
Liver, many tissue, adipose tissue, & muscle
Actions of Growth Hormone (GH):
Response in the liver that activates long loop feedback, to where?
Final result?
Increase in insulin-like growth factor secretion activates long loop negative feedback to the Anterior Pituitary or Hypothalamus.
Final Result of Liver: activation of many tissues to increase cell division & other growth promoting events
Actions of Growth Hormone (GH):
Effect of increased secretion in many tissues:
Actions of Growth Hormone (GH):
- Incease* in protein synthesis
- Increase* in insulin-like factor secretion
Actions of Growth Hormone (GH):
Effect of increased secretions in Adipose Tissue:
Decrease in glucose uptake
Increase in lipolysis
Actions of Growth Hormone (GH):
Affect secretions have on muscle:
Decreased glucose uptake
Increase AA uptake
Actions of Growth Hormone (GH):
Overall result of secretions on many tissues, adipose tissue and muscle:
Provide energy and substrates for growth
calcification
depositing of calcium phosphate to allow osteoblasts form osteoid
cell that makes bone through calcification
osteoblasts
term for bone?
osteoid
cell that resorbs bone through secretionof acid an enzymes
osteoclasts
cell that maintains a surrounding osteoid
osteocyte
bone growth formation of cells?
osteoblasts –> osteocyte
dwarfism, gigantism & acromegaly (
dwarfism: decreased GH secretion in children
gigantism: increased GH secretion in children
acromegaly: increased GH secretion in adults
“square jaw effect”: thickening of GH, due to excess uptake by body builders
Other hormone affecting growth, required for the synthesis of GH * permissive for GH actions
thryoid hormone
Other hormone affecting growth, permissive for GH actions
insulin
Other hormone affecting growth: little role in childhood growth, important for pubertal growth spurt, actively promotes growth during puberty
Sex hormones
Other hormone that inhibits growth; example when taken
Glucocorticoids; taken exogenously to decrease chances of new organ rejection in surgery
location of thyroxine production
thyroid follicles

active & inactive form of thyroxine
triiodothyronine: active, storage form
tetraiodothyronine: inactive, carrier form
7 Step Synthesis & secretion of thyroid hormones

Secretion of Thyroid Hormones:
Location and initial stimulus?
Location & initial physiological response?
Location & next cascade of physiological responses due to specific hormone release?
Secretion of Thyroid Hormones:
- Increased TRH secretion in Hypothalamus
- Stimulates increased TSH secretion in Anterior Pituitary
- Stimulates increased T3 and T4 secretion in the Thyroid Gland
- Final Result: T3 stimulates increased T3 in plasma
- T4 stimulates increased T4 in plasma
- T4 stimulates Liver, kidneys, & other target cells to produce T3
- Final Result: T3 stimulates increased T3 in plasma
Secretion of Cortisol:
Describe the initial stimuli, 2 physiological responses and locations and location/final result
- Initial stimuli: stress and circadian rhythm
- Increased CRH secretion in the Hypothalamus
- Increased ACTH secretion in the anterior pituitary
- Final Result: Increased cortisol secretion in the Adrenal Cortex (negative feedback to Anterior Pituitary or hypothalamus)
2 functions of the Stress hormone
- Mobilizes energy stores
- Suppresses immune response
General Adaptation Syndrome?
Functions?
Response to Stress- Flight or Flight
- Increased* cortisol secretion
- Increased* sympathetic activity
- Increased* epinephrine secretion
- Increased* ADH release
- Increased* angiotensin 2 production
Mobilize energy stores & maintain blood pressure