Hormonal Cycles

Again, select "blood glucose level" for your controlled condition, but this time, select "decrease" for your stimulus. Glucagon will be your hormonal choice. Exercise, or not eating recently, will cause blood glucose levels to fall. Glucagon is stimulated from the pancreatic islets. Describe its affect; it's role in re-establishing homeostasis.

Glucagon will give you the sugars you need to fuel yourself throughout the day.

Target Cell Action

Initiates response in cell

What is the overall affect of insulin on blood glucose levels?

Insulin lowers the glucose levels in the blood.

Describe how insulin affects the liver cells.

Insulin makes glucose into glycogen and stores it in the liver cells.

Describe how increased blood glucose levels respond to increase insulin levels.

Insulin makes the blood glucose levels decrease making glucose into glycogen stored in the liver.

How does calcitonin contribute to homeostatic balance?

- Inhibits the activity of osteoblasts - Stimulates osteocytes - Osteoclasts to reabsorb bone - Release calcium and phosphate ions into blood

Describe cortisol's affect on muscle cells. How does this contribute to homeostasis?

- Promotes the breakdown of muscle proteins to amino acids - liver converts these excess amino acids to glucose which enter the blood

How does hGh affect adipose tissue?

- decrease glucose uptake - increase break down of fat - decrease fat stored

Now, investigate the affect of GHRH/hGh on decreasing blood glucose levels. How do these hormones affect the liver in response to declining blood glucose levels?

- increase protein synthesis - decrease glucose uptake - keep as much glucose in the blood as possible

How does hGh contribute to homeostatic balance?

- prevent obesity - prevent unhealthy weight - keep you in shape

Continue your exploration of cortisol. Describe its affect on adipose tissue and how this affects homeostasis.

- promotes the metabolism of fatty acids rather then carbohydrates - spares glucose for brain

Explain cortisol's role in glycogenolysis and gluconeogenesis. How do these contribute to homeostasis?

- shuts down the production of glycogen to prepare glucose to deal with stress

Response

Action resulting from stimulus

Stimulus

Activiates Activity

What affect does ACTH have on the target cells within the adrenal cortex?

Controls the manufacture and secretion of certain hormones from the adrenal cortex.

Hormone

Endocrine gland secretes and body fluid transports

Target Cell

Specific cell were hormone has effect

Describe how insulin affects adipose cells.

Stores glucose here to prevent high glucose levels in the blood.

Production Cell

The cell that produces change

Summarize how PTH affects blood calcium levels?

To maintain the blood calcium level within normal levels