Homeostasis
What is homeostasis?
The process of maintaining a stable internal environment.
What are the two types of feedback mechanisms?
Negative and Positive feedback
What is the main purpose of cellular respiration?
To release energy from glucose and transfer it into ATP that cells can use.
Which organ releases insulin to help regulate blood glucose?
The pancreas.
What is thermoregulation?
The process of keeping body temperature within a suitable range.
Name one example the human body regulated to maintain homeostasis.
Body temperature (sweating/shivering), blood glucose, or water balance.
What type of feedback usually brings a changing condition back toward its normal state?
Negative feedback
Which type of cellular respiration uses oxygen: aerobic or anaerobic?
Aerobic respiration.
After a meal, blood glucose rises. Which hormone helps bring it down: insulin or glucagon?
Insulin.
What is one way the body loses heat when it is too hot?
Sweating and evaporation, and widening skin blood vessels.
Why does your body need to maintain homeostasis even when the outside environment changes?
To keep internal conditions stable so cells can function properly.
In a feedback loop, what is the role of a receptor?
It detects a change or stimulus.
Name two products of aerobic cellular respiration besides ATP.
Carbon dioxide and water.
Blood glucose falls between meals. What hormone is released by the pancreas?
What SPECIFIC part of the body help regulate body temperature (thermoregulation)?
The hypothalamus
A person becomes dehydrated after exercising? How can this challenge homeostasis?
Water loss changes the body's water balance. The body responds by conserving water and triggering thirst.
Put these parts in order: response, stimulus, control center, receptor, effector.
Stimulus → receptor → control center → effector → response.
Why can a person’s muscles begin using anaerobic pathways during intense exercise?
When oxygen delivery cannot keep up with demand, muscle cells can make some ATP without using oxygen, but less ATP is produced.
After eating a large meal, blood glucose levels rise. The pancreas releases ___________, which signals the liver to ____________ glucose as glycogen.
After eating a large meal, blood glucose levels rise. The pancreas releases insulin, which signals the liver to store glucose as glycogen.
What are shivering and narrowing skin blood vessels responses to?
Cold conditions or a body temperature that is below its normal range.
A runner's muscles use more energy during a race. Explain why the body must coordinate several organ systems to maintain homeostasis.
Muscles need more oxygen and glucose and produce more carbon dioxide and heat. The respiratory and circulatory systems help deliver materials, remove wastes, and regulate temperature.
A person's body temperature rises. Receptors detect the change, the brain processes the information, and sweat glands become active. Identify the stimulus, receptor, control center, effector, and response.
Stimulus: change in body temperature; Receptors: temperature-sensitive receptors; Control Center: hypothalamus in the brain; Effectors: sweat glands (and skin blood vessels); Response: sweating increases heat loss, helping temperature fall.
Compare aerobic and anaerobic cellular respiration in terms of oxygen use and ATP production.
Aerobic respiration uses oxygen and produces much more ATP. Anaerobic pathways do not use oxygen and produce less ATP; in human muscle, they produce lactic acid.
Explain how negative feedback regulates blood glucose after a person eats a carbohydrate-rich meal.
Blood glucose rises; pancreatic cells release insulin; body cells take up more glucose and the liver stores glucose as glycogen; blood glucose moves back toward its normal range.
A student runs outside on a hot day. Describe two body responses that help prevent overheating and explain how each helps.
Sweating cools the skin as it evaporates; the blood vessels expand which increases blood flow near the skin so more heat can leave the body.