Homeostasis

FOR GCE O LEVEL PURE BIOLOGY.

What is Homeostasis?

• Homeostasis is the maintenance of a constant internal environment

What is negative feedback?

• It is a sequence of events that are triggered by a certain stimulus to counteract the change and return the body to its original set-point

Describe how is Water Potential being Regulated in the Bloodstream. (high W.P)_

(Acronym: Wealthy Otters Ate Custard Pudding Dessert.)

• The osmoreceptors in the hypothalamus detects the increase in water potential in the bloodstream. Nerve impulses are transmitted to the Pituitary Gland to release secrete less ADH into the bloodstream.

• As a result, the cells in the collecting ducts of the kidneys become less permeable to water, allowing less water to diffuse into the collecting duct’s cells.

• Furthermore, the urine that is excreted out is more dilute as there is higher water content in the urine being passed out from the body.

Describe how the Temperature of the Body is being Regulated.(High Temperature)

• Acronym: MASS

• There is a temperature increase in the body, which causes the metabolic rate of the body to decrease as the rate of aerobic respiration in the mitochondria decreases to release less energy.

• The Arterioles in the skin began to dilate, to allow for more blood to flow into the capillaries nearer to the surface of the skin to lose more heat to the surroundings.

• The sweat glands in the body begin to produce more sweat on the skin surface, so that more latent heat is lost to the surroundings to decrease body temperature through the evaporation of more water.

What increases the Risk Factors of getting Diabetes Mellitus (Type 2)

• Eating unhealthy and oily foods./Unhealthy Diet

• Living a Sedentary Lifestyle.

• Obesity

• Family History of Diabetes Mellitus.

• Your Age Group

What are some preventative measures?

• Exercising Regularly.

• Having a Healthy Diet.

What are the Symptoms of Diabetes?

• Presence of Glucose in the Urine (elevated levels)

• Frequently feeling thirsty

• Frequently having to urinate

• Frequently feeling faint or dizzy

• Unexpected Weight Loss

• Feeling very Fatigued

• Wounds taking Longer to heal

How is Blood Glucose Level being Regulated in the Body?

Receptors	The Islets of Langerhans detect the higher blood glucose in the bloodstream.	The Islets of Langerhans detect the lower blood glucose in the bloodstream.
Secretion of Hormones	The Islets of Langerhans send signals to stimulate the liver to produce more insulin.	The Islets of Langerhans send signals to stimulate the liver to produce more glucagon
Effect	Causes the Liver to produce more insulin, and muscle and liver cells to be more permeable to glucose. In the liver, glucose is being converted back into glycogen, hence reducing blood glucose levels in the body.	Causes the liver to produce more glucagon, so that glycogen is being converted back into glucose to increase blood sugar levels. The liver and muscle cells also become more permeable to glucose, allowing for glucose to diffuse in. Increasing Blood Glucose Levels.
Set-point is restored	This process continues until Blood Glucose Levels become Normal and the Corrective Mechanism and Negative Feedback is Halted.	This process continues until Blood Glucose Levels become Normal and the Corrective Mechanism and Negative Feedback is Halted.