Nervous System
What organ controls your thoughts, memory, and senses?
Brain
What organ pumps blood through your body?
Heart <3
What type of tissue connects muscle to bone?
Tendons
What gas do you breathe in that your body needs?
Oxygen
Where does digestion begin?
What connects mouth to stomach?
In the mouth
Esophagus
Which part of your body sends signals between the brain and the rest of the body?
Spinal cord
Which blood cells carry oxygen?
RBCs
What kind of joint is your elbow?
Hinge joint
Where in the lungs does oxygen enter the blood?
Alveoli
What does the stomach use to help break down proteins and kill germs in food?
Stomach acid
If you touch something sharp, why do you pull away before feeling pain?
Because the spinal cord controls reflexes before the brain processes pain
Why is the left side of the heart stronger than the right?
Because it has to pump blood to the entire body, not just to the lungs.
Why are bones strong and slightly flexible?
Because they contain hard minerals (like calcium) and flexible protein (collagen).
Why do you breathe faster when you run?
Because your body needs more oxygen and must remove more carbon dioxide.
How does the body know the difference between its own cells and harmful invaders like viruses or bacteria?
It recognizes antigens — unique markers on pathogens — and uses them to identify what is “foreign” versus “self.”
Why are some nerve signals faster than others?
Neurons with myelin sheaths conduct signals more quickly.
Why might someone feel weak and dizzy if they lose a lot of blood?
Because less blood means less oxygen is being delivered to their cells.
What are the three types of muscle in your body — and where is each one found?
Skeletal (attached to bones), cardiac (heart), and smooth (internal organs like the stomach and blood vessels).
Why do people with asthma have trouble breathing?
Their airways become inflamed and narrow, blocking airflow.
What do B cells and T cells do to help protect your body?
→ B cells make antibodies. T cells help destroy germs and infected cells.
A person has trouble speaking and balancing after hitting their head. Which parts of their brain are likely affected?
The frontal lobe (for speech) and the cerebellum (for balance).
What are the four major parts of blood — and what does each one do?
Red blood cells carry oxygen, white blood cells fight infection, platelets help clot blood, and plasma carries nutrients, hormones, and waste.
Why do you have both voluntary and involuntary muscles — and how do they work differently?
Voluntary muscles (like skeletal) let you control movement, while involuntary muscles (like smooth and cardiac) work automatically to keep organs functioning.
What would happen to your blood pH if you held your breath too long?
Carbon dioxide would build up, making the blood more acidic.
What’s the difference between innate and adaptive immunity?
Innate immunity acts fast and fights all germs the same way. Adaptive immunity takes longer but remembers specific germs.