Human Body Systems
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
The Skeletal System
SubtopicThe Skeletal System under Human Body Systems for Grade 3 IB.
Preview questions (no answers)
- 1.
Which of these is NOT a function of the skeletal system?
A.Giving the body shape
B.Protecting organs
C.Helping the body move
D.Thinking of new ideas
- 2.
What would the human body look like if we had no skeleton?
A.A tall tower
B.A floppy pile on the floor
C.A hard statue
D.A square box
- 3.
Which set of bones protects your lungs while you breathe?
A.The skull
B.The rib cage
C.The pelvis
D.The leg bones
- 4.
Which part of the body has a joint that allows you to nod your head 'yes' or 'no'?
A.The ankle
B.The neck
C.The elbow
D.The knee
- 5.
Why is a young child's skeleton generally more flexible and less likely to break than an adult's skeleton?
A.Children have fewer bones than adults.
B.Children's bones contain more cartilage that hasn't turned into hard bone yet.
C.Children's bones are hollow inside.
D.Children do not have joints in their arms or legs yet.
- 6.
Which part of the skeleton is shaped like a bowl to support the weight of the upper body and protect organs like the bladder?
A.The rib cage
B.The pelvis
C.The skull
D.The spine
- 7.
What is the common name for the 'scapula', the flat, triangular bone located on the upper back?
A.Collar bone
B.Shoulder blade
C.Shin bone
D.Tail bone
- 8.
In the human body, where would you find a 'pivot joint' that allows you to turn your head from side to side?
A.Between the first two vertebrae of the neck
B.In the ankle
C.In the hip
D.Between the ribs
- 9.
Which bone is commonly known as the 'collarbone' and helps hold the shoulder out away from the body?
A.Clavicle
B.Scapula
C.Sternum
D.Tarsal
- 10.
Which of these activities is most beneficial for increasing bone density and making the skeletal system stronger?
A.Weight-bearing exercises like running or jumping
B.Watching educational videos
C.Sleeping for 10 hours
D.Sitting perfectly still
Download the worksheet for Human Body Systems - The Skeletal System to practice offline. It includes additional chapter-level practice questions.
The Muscular System
SubtopicThe Muscular System under Human Body Systems for Grade 3 IB.
Preview questions (no answers)
- 1.
When you practice a move like throwing a ball over and over, your muscles 'remember' how to do it. What is this called?
A.Muscle memory
B.Muscle forgetting
C.Bone memory
D.Skin memory
- 2.
Where do your muscles get the energy they need to move and work?
A.From the air only
B.From the food you eat
C.From your shoes
D.From the TV
- 3.
Which muscles are used to open and close your eyes quickly when something flies toward your face?
A.Bicep muscles
B.Eyelid muscles
C.Toe muscles
D.Stomach muscles
- 4.
Why does your body shiver when you are cold?
A.To make you look funny
B.To help the muscles create heat
C.To help you fall asleep
D.To make you colder
- 5.
Which of these is a way to maintain a healthy muscular system?
A.Staying still as much as possible
B.Eating a balanced diet and regular exercise
C.Only eating candy for energy
D.Drinking very little water
- 6.
If you are balancing on one leg, which muscles are working to keep you upright?
A.Only the brain muscles
B.The muscles in your core and legs
C.Only the muscles in your arms
D.No muscles are used during balancing
- 7.
What do we call the state when a muscle is not contracting and is in a resting position?
A.Tired
B.Relaxed
C.Compressed
D.Stretched
- 8.
What would be the most immediate result if the body ran out of ATP (the energy molecule) in the middle of a physical activity?
A.The muscles would start to glow.
B.The muscles would be unable to contract or release, causing the body to stop moving.
C.The bones would take over and finish the movement.
D.The skin would turn into muscle to provide extra energy.
- 9.
Which of these is a characteristic that smooth muscles and cardiac muscles have in common?
A.They are both under voluntary control.
B.They are both attached directly to the skeleton.
C.They both function without us having to consciously think about them.
D.They both have the same striped appearance under a microscope.
- 10.
How do the muscular and nervous systems work together to control the speed of a movement, such as slowly lowering a glass of water?
A.The brain stops sending signals so the muscle just turns off.
B.The brain sends carefully timed signals to both the contracting and relaxing muscles to create smooth, controlled resistance.
C.The skeletal system provides a brake to slow down the muscle.
D.The glass of water tells the muscle how fast to move.
Download the worksheet for Human Body Systems - The Muscular System to practice offline. It includes additional chapter-level practice questions.
The Nervous System
SubtopicThe Nervous System under Human Body Systems for Grade 3 IB.
Preview questions (no answers)
- 1.
If you want to move your finger to point at a bird, where does the instruction start?
A.In your fingernail
B.In your brain
C.In your elbow
D.In your wrist
- 2.
Which of these is NOT one of the three main components of the human nervous system?
A.The Brain
B.The Spinal Cord
C.The Stomach
D.The Nerves
- 3.
Which part of the body acts as the 'receiver' for sounds before sending them to the brain?
A.The Nose
B.The Ears
C.The Tongue
D.The Eyes
- 4.
When you see a bright light and your eyes squint, which system is in charge of this reaction?
A.The Nervous System
B.The Circulatory System
C.The Digestive System
D.The Respiratory System
- 5.
Which part of the body acts as the 'highway' for messages traveling between the brain and the rest of the body?
A.The stomach
B.The spinal cord
C.The ribs
D.The liver
- 6.
How does the nervous system help you during a game of 'Simon Says'?
A.It helps you hear the instructions and tells your body when to move
B.It makes your voice louder so Simon can hear you
C.It changes the color of your clothes during the game
D.It makes sure you don't get hungry while playing
- 7.
What is the name for a change in the environment (like a bright light) that causes the nervous system to react?
A.A stimulus
B.A sleep
C.A memory
D.A muscle
- 8.
Which of these best explains why your brain is considered part of a 'system'?
A.Because it works alone and doesn't need help from other parts
B.Because it is made of only one type of large cell
C.Because it works together with the spinal cord and nerves to perform a function
D.Because it is the only part of the body that uses energy
- 9.
Why do you blink when someone claps their hands loudly near your face, even if you didn't mean to?
A.The nervous system triggers a fast, automatic response to protect your eyes
B.The sound waves physically push your eyelids closed
C.Your brain decides to blink after thinking about it for a few minutes
D.Your eyes are trying to hide from the loud noise
- 10.
A scientist is studying 'nerves.' She finds that they look like long, thin threads. Why is this shape useful for their job?
A.It helps them tie the bones together so they don't fall
B.It allows them to reach long distances across the body to carry signals
C.It makes it easier for them to absorb food from the stomach
D.It helps them stay invisible so nobody can see them
Download the worksheet for Human Body Systems - The Nervous System to practice offline. It includes additional chapter-level practice questions.
Nutrition and Healthy Growth
SubtopicNutrition and Healthy Growth under Human Body Systems for Grade 3 IB.
Preview questions (no answers)
- 1.
Which organ in your body is responsible for sending signals that tell you when you are hungry?
A.Your feet
B.Your brain
C.Your elbows
D.Your hair
- 2.
Which of these is a vegetable that grows underground?
A.Tomato
B.Potato
C.Apple
D.Banana
- 3.
Why is eating a healthy breakfast helpful for students?
A.It makes you go to sleep
B.It provides the energy needed to start the school day
C.It makes your backpack lighter
D.It helps you see in the dark
- 4.
What is the name of the watery liquid in your mouth that helps soften food as you chew?
A.Juice
B.Saliva
C.Blood
D.Sweat
- 5.
Which of these is a sign that a child is growing at a healthy rate?
A.Their shoes and clothes gradually become too small
B.They stay the exact same height for five years
C.Their hair changes color every week
D.They stop needing to eat food
- 6.
In addition to healthy food, how does playing outside help your bones stay strong?
A.The fresh air turns into calcium
B.Physical activity puts healthy stress on bones, making them denser and stronger
C.Walking on grass makes your feet softer
D.The wind helps the bones grow longer
- 7.
Why is cooking certain foods, like potatoes or meat, an important part of nutrition?
A.It makes the food harder to chew
B.It can make the food easier to digest and safer to eat by killing bacteria
C.It removes all the calories from the food
D.It turns the vegetables into fruits
- 8.
Which of these choices represents a meal with the best balance of 'Energy, Growth, and Protection'?
A.Grilled chicken, brown rice, and steamed broccoli
B.A large bowl of white sugar and a glass of juice
C.Only a plate of butter and oil
D.A bag of salty potato chips and a soda
- 9.
Why is 'sleep' considered just as important as 'nutrition' for a child's healthy growth?
A.The body releases growth hormones and repairs tissues most effectively during sleep
B.The body digests all its food only when the eyes are closed
C.Sleep turns water into muscle
D.You don't use any energy when you are awake
- 10.
If you compare the human body to a building, which nutrient acts as the 'bricks' and which acts as the 'electricity'?
A.Bricks: Protein; Electricity: Carbohydrates
B.Bricks: Fats; Electricity: Water
C.Bricks: Vitamins; Electricity: Minerals
D.Bricks: Sugar; Electricity: Protein
Download the worksheet for Human Body Systems - Nutrition and Healthy Growth to practice offline. It includes additional chapter-level practice questions.