chapter 47 Flashcards
What is the metabolism?
Refers to all the bodily activities and chemical reactions in an organism that maintain life
What is metabolic rate?
rate at which an organism uses energy to power such reactions
Absorptive phase
occurs when ingested nutrients enter blood stream from the alimentary canal
Post absorpative stage
occurs when alimentary canal is empy of nutrients, and bodys stores are used
What is the carbohydrate monomer that is absorbed from the digestive tract?
Glucose
what are the two major energy sources during the absorptive phase?
glucose and triglycerides
What happens when glucose enters the body during absorptive state?
-it can be used immediately as fuel.
-it can be stored as glycogen in the liver.
-it can be stored as glycogen in the muscles
-it can be converted to a triglyceride and then stored in fat cells
what is the major consumer of glucose?
skeletal muscle
What happens if excess glucose?
stored in liver, triglyceride in adipose cells.
what increases the absorption of glucose?
insulin
what is the location of glucose transporter proteins?
in the membrane of intracellular vesicles
what occurs during the absorptive period ?
-glucose absorption from the gut is high.
-glucose utilization by cells is high
-synthesis of triglycerides is high
breakdown of glycogen is low.
what are Absorbed triglycerides?
-Too large to diffuse acorss plasma membrane of intestinal epithelial cells
-Digested into monoglycerides and fatty acids
-Diffuse into intestinal epithelial cells
What do triglycerides enter as?
enter the blood circulation as chylomicrons for lymph and blood transport
where are triglycerides stored?
adipose tissue
Why is glucose essential to the CNS?
uses for energy
What occurs during post absorptive state ?
synthesis of glycogen and triglycerides slows and breakdown begins
what maintains blood glucose ?
glucose sparing
what does glucose sparing depend on ?
on lipolysis because it releases fatty acids
what is glucose sparing?
the increase in fat utilization seen in most tissues and organs during periods of low glucose availability
where do excess amino acids go?
are converted by liver cells into fatty acids and then triglycerides
what are Endotherms
-generate their own heat
-Manly relatively narrow range of body temperatures
BMR measures within its thermoneutral zone
what are the Ectotherms?
-body temperature changed with environments
BMR measured at standard temperature for each species
-Approximated average temperature normally encountered
What are homeotherms ?
do not maintain a constant temperature
and are affected by extreme climate, exercise and sleep
-have stable body temperature
-can quickly adjust
