3.6.4.1 Principles of homeostasis and negative feedback

Front

What is homeostasis in mammals primarily responsible for?

Back

Maintaining the internal environment within restricted limits

Answer explanation

Homeostasis in mammals is primarily responsible for maintaining the internal environment within restricted limits, ensuring stable conditions for bodily functions despite external changes.

Front

Why is maintaining a stable core temperature important for enzyme activity?

Back

It ensures enzymes do not denature

Answer explanation

Maintaining a stable core temperature is crucial because it ensures enzymes do not denature. High temperatures can disrupt the enzyme's structure, leading to loss of function, while optimal temperatures promote proper activity.

Front

How does a stable blood pH affect enzyme activity?

Back

It allows enzymes to function optimally

Answer explanation

A stable blood pH is crucial for enzyme activity, as it allows enzymes to maintain their optimal shape and function. Deviations in pH can lead to reduced activity or inactivation, making the correct choice "It allows enzymes to function optimally."

Front

What is the significance of maintaining a stable blood glucose concentration?

Back

It ensures a constant supply of respiratory substrate

Answer explanation

Maintaining stable blood glucose levels is crucial as it ensures a constant supply of respiratory substrate, which is essential for energy production in cells. This prevents energy deficits that can impair bodily functions.

Front

How does blood glucose concentration affect the water potential of blood?

Back

High glucose concentration decreases water potential

Answer explanation

High glucose concentration decreases water potential because glucose is a solute that increases osmotic pressure, leading to a lower water potential in the blood.

Front

What role does negative feedback play in homeostasis?

Back

It restores systems to their original level

Answer explanation

Negative feedback is crucial in homeostasis as it helps restore systems to their original level after a change occurs, maintaining balance and stability within the body.

Front

Why is it beneficial for organisms to have separate mechanisms for negative feedback?

Back

It provides a greater degree of control

Answer explanation

Having separate mechanisms for negative feedback provides a greater degree of control, allowing organisms to fine-tune their responses to various stimuli and maintain homeostasis more effectively.

Front

What happens to enzymes if the core temperature of a mammal is too high?

Back

Enzymes denature and lose function

Answer explanation

If a mammal's core temperature is too high, enzymes denature, meaning they lose their specific structure and function. This disrupts metabolic processes, making 'Enzymes denature and lose function' the correct answer.

Front

Consequence of unstable blood pH?

Back

Enzyme denaturation

Answer explanation

Unstable blood pH can lead to enzyme denaturation, which disrupts their structure and function. This negatively impacts metabolic processes, unlike enhanced activity or improved rates, which require stable pH levels.

Front

What is the primary function of glucose in the blood?

Back

To serve as a respiratory substrate

Answer explanation

The primary function of glucose in the blood is to serve as a respiratory substrate, providing energy for cellular processes through metabolism. It is not a structural component, nor does it regulate blood pressure or transport oxygen.