Pancreas
- Secretes hormones as an endocrine gland
- Secretes digestive juice into digestive tract as an exocrine gland
- Control level of blood glucose
- There is two type of cells in the gland:
o Alpha cells – glucagon
Increase blood level of glucose by breakdown of
glycogen
Convert noncarbohydrates into glucose by the liver
Glucagon is controlled by negative feedback
Low blood glucose stimulates the secretion of glucagon
o Beta cells – insulin
Decrease the blood level of glucose by stimulating the
liver to form glycogen
Increase protein synthesis and stimulates adipose cells
to store fat
Insulin is controlled by negative feedback
High blood glucose stimulates the release of insulin
Diabetes Mellitus
- Metabolic disease due to lack of insulin or the inability of cells to recognize insulin
- Type 1 diabetes
o Autoimmune disorder
o Beta cells are destroyed, insulin cannot be produced/ decreases
o Insulin needs to be injected everyday
- Type 2 diabetes
o Diseases of lifestyle, happen later in life
o Beta cells are not destroyed, but the cells stop response
o Insulin is produced but is not recognized by cells, glucose cannot be push into
the cells
Pineal gland
- Located near the upper portion of the thalamus
- Secretes melatonin, involved in the regulation of circadian rhymes – sleep cycle
- Released at night and suppressed during the day
, Thymus gland
- Lies between the lung, behind the sternum
- Secretes Thymosins – which affect production and differentiation of T lymphocytes (a
type of white blood cells)
- Important for immunity
- The gland is largest in children and shrink with age
Stress and health
- Factor that serves as stressors to the body can
threaten homeostasis
- Stressors increase the activity of sympathetic nervous
system
- Types of stress:
o Physical stress
Threatens the survival of tissues
E.g. extreme cold, prolonged exercise
o Psychological stress
Results from real or perceived dangers
E.g. feeling dangers, depression, fear
Responses to Stress
- Alarm stages -> Fight or flight responses
o Increases blood glucose and fatty acid
o Increase heart rate, breathing rate, blood pressure
o Dilates air passages
o Send more blood to skeletal muscle and less to skin and digestive organs
- Resistance stage -> increases ACTH secretion, increase cortisol secretion from the
adrenal cortex
o Actions of cortisol from the adrenal cortex
o Increase blood amino acid fatty acid release and glucose formation from
noncarbohydrates
o LONG TERM -> can be harmful!
Increase risk of high blood pressure, GI ulcers, some cancers
- Secretes hormones as an endocrine gland
- Secretes digestive juice into digestive tract as an exocrine gland
- Control level of blood glucose
- There is two type of cells in the gland:
o Alpha cells – glucagon
Increase blood level of glucose by breakdown of
glycogen
Convert noncarbohydrates into glucose by the liver
Glucagon is controlled by negative feedback
Low blood glucose stimulates the secretion of glucagon
o Beta cells – insulin
Decrease the blood level of glucose by stimulating the
liver to form glycogen
Increase protein synthesis and stimulates adipose cells
to store fat
Insulin is controlled by negative feedback
High blood glucose stimulates the release of insulin
Diabetes Mellitus
- Metabolic disease due to lack of insulin or the inability of cells to recognize insulin
- Type 1 diabetes
o Autoimmune disorder
o Beta cells are destroyed, insulin cannot be produced/ decreases
o Insulin needs to be injected everyday
- Type 2 diabetes
o Diseases of lifestyle, happen later in life
o Beta cells are not destroyed, but the cells stop response
o Insulin is produced but is not recognized by cells, glucose cannot be push into
the cells
Pineal gland
- Located near the upper portion of the thalamus
- Secretes melatonin, involved in the regulation of circadian rhymes – sleep cycle
- Released at night and suppressed during the day
, Thymus gland
- Lies between the lung, behind the sternum
- Secretes Thymosins – which affect production and differentiation of T lymphocytes (a
type of white blood cells)
- Important for immunity
- The gland is largest in children and shrink with age
Stress and health
- Factor that serves as stressors to the body can
threaten homeostasis
- Stressors increase the activity of sympathetic nervous
system
- Types of stress:
o Physical stress
Threatens the survival of tissues
E.g. extreme cold, prolonged exercise
o Psychological stress
Results from real or perceived dangers
E.g. feeling dangers, depression, fear
Responses to Stress
- Alarm stages -> Fight or flight responses
o Increases blood glucose and fatty acid
o Increase heart rate, breathing rate, blood pressure
o Dilates air passages
o Send more blood to skeletal muscle and less to skin and digestive organs
- Resistance stage -> increases ACTH secretion, increase cortisol secretion from the
adrenal cortex
o Actions of cortisol from the adrenal cortex
o Increase blood amino acid fatty acid release and glucose formation from
noncarbohydrates
o LONG TERM -> can be harmful!
Increase risk of high blood pressure, GI ulcers, some cancers
