WEEKS 5 & 6: Pancreas and Diabetes Flashcards
The average adult human has about … litres of blood
5
Humans derive energy from food in what 3 main forms?
Carbohydrates, proteins
and lipids.
During digestion we absorb … from carbohydrates, … from proteins and … from lipids.
glucose
amino acids
fatty acids
If we do not utilise consumed nutrients immediately for energy we store them as larger macromolecules via … reactions.
anabolic
T or F
Glycogen has a similar structure to starch?
T
T or F
Glucose molecules can be easily joined together to form the storage molecule glycogen
T
Glycogen is mainly stored in the … and …
liver and muscles
When you exercise muscle glycogen can be catabolised to provide energy for …
contraction
(But glucose is also taken up from the blood to ensure muscles have sufficient energy to
keep contracting.)
T or F
Neurons in the central nervous system can store glycogen.
F
It is estimated that the brain requires up to …% of your body’s glucose.
50%
T or F
A constant supply of glucose must be provided for normal brain function.
T
Ketone bodies, are by-products of ……
fat-metabolism
When glucose is limited, the brain is capable of switching to an alternative energy source to maintain normal function. This “back-up” energy source is called …
ketone bodies
T or F
Glucose is usually present in the urine.
F
When glucose is present in the urine this is an indicator of?
The glucose load in the kidney tubules exceeds the reabsorption capacity, aka hyperglycemia.
T or F
Plasma glucose concentrations do not fluctuate that much across the day, despite consuming meals.
T
What two metabolic hormones control glucose homeostasis?
Insulin and glucagon
Why is glucagon a difficult hormone to measure in blood?
It is rapidly degraded and thus has a very short half-life, of less than 6 minutes.
Glucagon is important between meals in the ….. state where it increases blood glucose.
post-absorptive
…. is important in preventing any decline in blood glucose
between meals.
glucagon
When are hormones aside from glucagon and insulin required for glucose homeostasis?
During starvation
Insulin prevents …
a) excess blood glucose “hyperglycaemia”
b) low blood glucose “hypoglycaemia”.
a
Glucagon prevents …
a) excess blood glucose “hyperglycaemia”
b) low blood glucose “hypoglycaemia”.
b)
What are the consequences of chronic hyperglycemia?
Osmotic diuresis, frequent urination, increased thirst and damage to blood vessels.
T or F
The pancreas has both exocrine and endocrine functions.
T
The pancreas is a small, leaf-like gland located in the …, posterior to the stomach.
retroperitoneum
The retroperitoneum is posterior to the …
stomach
T or F
Acinar cells are endocrine cells
F
They are exocrine
T or F
acinar cells arranged in lobules
T
What do acinar cells secrete?
a range of digestive enzymes, sodium bicarbonate and other electrolytes
Where do acinar cells secrete digestive enzymes into?
The duodenum (part of the small intestines)
T or F
The Islets of Langerhans are 98%-99% of pancrease mass
F
(only 1-2% of pancreatic mass)
The islets of Langerhans secrete what into where?
hormones into systemic blood.
Are islets of langerhans cells part of the endocrine or exocrine systems?
Endocrine
Do beta cells in the islet of Langerhans produce insulin or glucagon?
Insulin
Do alpha cells in the islet of Langerhans produce insulin or glucagon?
Glucagon
T or F
Beta cells circle the edge of the islet of Langerhans whilst alpha cells are in the center.
F
Vice versa
What triggers glucagon release from alpha cells in the islet of Langerhans?
Amino acids
The pancreas receives oxygen-rich blood through the … system and gives off oxygen-poor blood flow through the … system
arterial
venous