Chapter 8 – Maintaining Balance in Organisms

What is negative feedback?

A response that reduces the effect of a stimulus to maintain homeostasis.

What is positive feedback?

A response that amplifies the stimulus

What is a behavioral response?

An action taken by an organism to maintain homeostasis

What is a physiological response?

Internal body adjustments to maintain balance

What organ systems are involved in homeostasis?

Circulatory, Digestive, Endocrine, Gas Exchange, Nervous, Urinary.

How does the urinary system help in homeostasis?

It filters waste and controls water/salt balance.

How does the endocrine system contribute to homeostasis?

It releases hormones that regulate body functions.

Give an example of negative feedback in the body.

Body temperature regulation: sweating when hot, shivering when cold.

Give an example of positive feedback in the body.

Contractions during childbirth intensify until delivery.

Why is homeostasis important?

It keeps internal conditions optimal for enzyme function and survival.

What is the difference between behavioral and physiological responses?

Behavioral = actions; Physiological = internal changes.

If your body gets too hot, what happens?

Blood vessels dilate, sweat glands release sweat and negative feedback lowers temperature.

What might happen if homeostasis fails?

The organism could suffer cell damage or death due to unstable internal conditions.

What is the role of the circulatory system in homeostasis?

Transports oxygen, nutrients, and waste to regulate internal conditions.

What is the role of the digestive system in homeostasis?

Breaks down food into nutrients that are absorbed to fuel the body.

What is the role of the nervous system in homeostasis?

Detects changes and coordinates responses using electrical signals.

What is the role of the gas exchange (respiratory) system in homeostasis?

Brings in oxygen and removes carbon dioxide to regulate blood pH and energy levels.

What organ releases insulin to lower blood sugar?

Pancreas

What organ filters blood and removes waste as urine?

Kidney

What organ helps with gas exchange by removing carbon dioxide and bringing in oxygen?

Lungs

What organ controls most body functions and sends signals through nerves?

Brain

What organ pumps blood to deliver oxygen and nutrients?

Heart

What organ is the main part of the integumentary system that helps with temperature control?

Skin

What organ produces sweat to cool the body?

Sweat glands

What organ detects changes in temperature and sends signals to respond?

Skin (sensory receptors)

What organ system includes the lungs and handles breathing?

Respiratory system

What organ system includes the heart and blood vessels?

Circulatory system