HOMEOSTASIS

Study for bIOOOooOO!!

What is a negative feedback loop?

A negative feedback loop is when a variable causes a counter-reaction that returns the body back to homeostasis.

What is the main purpose of thermoregulation?

Thermoregulation is the body's ability to control or maintain a stable internal temperature.

What example illustrates a positive feedback loop?

A baby pushing on the cervix causing more hormone release and contractions is an example of a positive feedback loop.

What are the components involved in the blood clotting process?

Platelets and fibrin are the two main components that form a blood clot.

What happens when glucose levels are low in the bloodstream?

When glucose levels are low, the alpha cells in the pancreas release glucagon to break down glycogen into glucose.

What are the defining features of feedback systems in the body?

Feedback systems have a receptor, an integrator/control center, and an effector.

How does an acid affect pH levels in a solution?

An acid lowers the pH of a solution by increasing the concentration of hydrogen ions (H+).

What is the role of hydroxide ions (OH-) in basic solutions?

Hydroxide ions decrease the hydrogen ion concentration, thus raising the pH of a solution.

Describe the process of water dissociation.

Water molecules can break apart, forming hydrogen ions (H+) and hydroxide ions (OH-) but this is very rare.

What term is used to describe a substance that accepts hydrogen ions?

hydrogen ion acceptor.

Whats is thermoregulation?

the body’s ability to control or maintain a stable internal temperature.

Capillary Action

is the process of a liquid flowing in a narrow space without the assistance of external forces like gravity.

Cohesion

Tendency of water molecule to stick together due hydrogen bonds

Adhesion

Water attracting to different substances

Endotherm

• (warm-blooded) needs to maintain an internal temperature. 

• Ex. humans (any mammals)

Ectotherm

(cold-blooded) temperature fluctuations do not need to maintain a constant internal body temperature.

Ex. snakes (reptiles)

What is H2O?

Water

What is OH^-_?

Hydroxide ion

What is H₃O⁺?

Hydronium ion

What is the relationship between acidity, basicity, and pH number?

The higher the pH the more basic (the less the H⁺ concentration the more OH^- concentration)

The lower pH the more acidic (the more the H⁺ concentration the less OH^- concentration)

Neutral (pH 7 —> # of H⁺ = # of OH^-