Structures
What are the levels of organization in the human body?
Cells → Tissues → Organs → Organ Systems → Organism
What is the main function of the respiratory system?
To bring oxygen in and remove carbon dioxide
Which two systems work together to deliver oxygen to cells?
Respiratory and circulatory
What are the two main parts of the nervous system?
Central nervous system and peripheral nervous system
What is homeostasis?
The body’s ability to maintain a stable internal environment
What organ in the circulatory system pumps blood?
The heart
What is the main function of the circulatory system?
To transport oxygen, nutrients, and wastes
Which two systems remove waste (liquid & gas) from the body?
Circulatory and excretory
What does the endocrine system use to send messages?
Hormones
What happens to your body when it gets too hot?
You sweat to cool down
What tiny air sacs in the lungs allow gas exchange?
Alveoli
What is the main function of the digestive system?
To break down food into nutrients the body can use
Which systems work together when your stomach growls?
Digestive and nervous
Compare the nervous and endocrine systems.
Nervous = fast electrical signals; Endocrine = slower chemical signals; both maintain balance
How do the circulatory and excretory systems maintain homeostasis?
Blood carries waste to kidneys to be filtered out
What organs are part of the excretory system?
Kidneys, bladder, ureters, urethra
What is the main function of the nervous system?
To control and coordinate body actions
The ovaries release hormones to prepare the uterus for pregnancy. Which systems are working together?
eproductive and endocrine
Which two systems control most of the body’s functions?
Nervous and endocrine
How do the nervous and endocrine systems help maintain homeostasis?
They send signals to control temperature, water, and energy balance
Which organ produces digestive juices to help break down food?
Stomach
What is the main function of the endocrine system?
To produce hormones that regulate body processes
Explain how the digestive, respiratory, and circulatory systems work together to produce energy.
Digestive breaks down food, respiratory brings oxygen, circulatory delivers both to cells for energy.
Why is it important for the nervous & endocrine systems to work together?
They coordinate body responses and maintain homeostasis.
What could happen if one system fails?
Other systems can’t function properly and homeostasis is lost leading to severe health issues or death.