Question

definition (in your own words)
illustration that represents the word
examples
positive feedback loop
non - examples (or the opposite of...)
more on other side →

Explanation:

Definition:

A positive feedback loop is a process where the output of a system amplifies the original stimulus, leading to an increase in the effect. For example, in a population growth scenario, more individuals lead to more offspring, which in turn leads to even more individuals.

Illustration:

We can represent a positive feedback loop with a diagram. Let's consider the growth of a bacterial colony. Start with a small number of bacteria. These bacteria reproduce, increasing the number of bacteria. The increased number of bacteria then have more opportunities to reproduce, leading to a rapid increase in the colony size. We can draw this as a cycle: Bacteria → Reproduction → More Bacteria → More Reproduction → Even More Bacteria...

Examples:

1. Melting of Arctic Ice: As the Earth's temperature rises, Arctic ice melts. Ice reflects sunlight (albedo effect), so when ice melts, more dark ocean water is exposed. Dark water absorbs more sunlight, leading to more heating, which causes more ice to melt.
2. Childbirth: During labor, the baby's head pushing on the cervix stimulates the release of oxytocin. Oxytocin causes stronger contractions, which push the baby's head more on the cervix, leading to more oxytocin release and stronger contractions until the baby is born.
3. Financial Bubble: As the price of an asset (like a stock) rises, more investors are attracted to buy it, driving the price up further. This attracts even more investors, creating a self - reinforcing cycle of price increases.

Non - examples (or the opposite of - ):

1. Thermostat in a Room: A thermostat senses the temperature. If the temperature is too high, it turns on the air conditioner to cool the room. When the temperature drops to the set point, it turns off the air conditioner. This is a negative feedback loop, as it works to maintain a stable temperature, unlike a positive feedback loop which amplifies a change.
2. Blood Glucose Regulation: When blood glucose levels rise, the pancreas releases insulin, which causes cells to take up glucose, lowering blood glucose levels. When blood glucose levels are low, the pancreas releases glucagon, which causes the liver to release glucose, raising blood glucose levels. This is a negative feedback loop that maintains blood glucose homeostasis.
3. Body Temperature Regulation in Humans: If the body temperature rises, sweating occurs to cool the body down. If the body temperature drops, shivering occurs to generate heat. This is a negative feedback mechanism to keep body temperature stable.

Answer:

• Definition: A process where a system's output amplifies the initial stimulus, increasing the effect.
• Illustration: Diagram of bacterial colony growth (Bacteria → Reproduction → More Bacteria → More Reproduction...).
• Examples: Arctic ice melting, childbirth, financial bubble.
• Non - examples: Thermostat regulation, blood glucose regulation, human body temperature regulation.