Concept
This "S" is something that can cause a reaction in an organism. Even the act of reading this prompt is an example!
What is a stimulus?
Any self-regulating process by which biological systems tend to maintain stability while adjusting to conditions for survival.
What is homeostasis?
Thermoregulation
Negative -- Temperature regulation in humans occurs constantly. Normal human body temperature is approximately 98.6°F. When body temperature rises above this, two mechanisms kick in the body begins to sweat, and vasodilation occurs to allow more of the blood surface area to be exposed to the cooler external environment. As the sweat cools, it causes evaporative cooling, while the blood vessels cause convective cooling. Normal temperature is regained. Should these cooling mechanisms continue, the body will become cold. The mechanisms which then kick in are the formation of goose bumps and vasoconstriction, in addition to shivering.
The messages sent between cells, to tell them what to do.
What are chemical signals?
The average human core temperature, in degrees Celsius.
What is 37?
A type of cell that receives and sends messages; messages go from the body to the brain, and back to the body.
What is a neuron?
Blood pressure
Negative -- Blood pressure needs to remain high enough to pump blood to all parts of the body, but not so high as to cause damage while doing so. If the pressure is too high or too low, a chemical signal is sent to the brain. The brain then sends a chemical signal to the heart to adjust the rate of pumping: if blood pressure is low, heart rate increases, while if blood pressure is high, heart rate decreases.
A complex system that sends messages throughout your body, to control everything you do. Think of it like the control system.
What is the nervous system?
In humans, this "e" word is what is happening when we lose heat when sweat (a liquid) changes to a gas (water vapor).
What is evaporation?
A loop system in which the system responds to stimuli either in the same direction (positive) or in the opposite direction (negative).
What is a feedback mechanism?
Fruit ripening
Positive -- In nature, a tree or bush will often suddenly ripen all of its fruit or vegetables, without any visible signal. Let's take apples: This will begin with the first apple to ripen. Once ripe, it gives off a gas known as ethylene (C2H4) through its skin. When exposed to this gas, the apples near to it also ripen. Once ripe, they too produce ethylene, which continues to ripen the rest of the tree in an effect much like a wave. This feedback loop is often used in fruit production, with apples being exposed to manufactured ethylene gas to make them ripen faster.
A long, single nerve cell within a neuron that usually directs impulses away from the cell body.
What is an axon?
Dogs don't have these -- that one reason they pants. When a human's core temperature gets too high, sweat is expelled from this place (TWO WORDS).
What is the sweat glands?
A state when chemical reactions are constant, but the end result is balance.
What is dynamic equilibrium?
Glucose (sugar) regulation
Negative -- Regulation of glucose in the body is done constantly. Normal levels should be between 60 and 140 mg/dL in order to supply cells of the body with its required energy. Too little glucose (hypoglycemia) starves cells, and too much glucose (hyperglycemia) creates a sticky, paralyzing effect on cells. A delicate balance is required to maintain normal BG levels.
When blood vessels get smaller to allow less blood to flow.
What is vasoconstriction?
This is the region of the brain that acts like an internal thermostat; in other words, it's the hypo- part that controls internal temperature.
What is the hypothalamus?
When blood vessels get bigger to allow more blood to flow.
What is vasodilation?
Blood clotting
Positive -- When tissue is torn or injured, a chemical is released. This chemical causes platelets in the blood to activate. Once these platelets have activated, they release a chemical which signals more platelets to activate, until the wound is clotted.
The ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is different.
What is thermoregulation?