Learn › Homi Bhabha Class 6 · Biology › Human Body Systems
Human Body Systems — Homi Bhabha Class 6 Biology MCQs with Solutions
Free Homi Bhabha Class 6 Biology Human Body Systems MCQs with step-by-step solutions covering Digestive System, Respiratory System, Circulatory System, Skeletal & Nervous Systems. Practise online on Prepizo — no login needed.
▶ Practise Human Body Systems online (free)
Subtopics
Sample questions with solutions
Q1 — Digestive System · easy · theory
Digestion of food begins in which part of the body?
A. The liver
B. The small intestine
C. The stomach
D. The mouth ✓ Correct
Solution: In the mouth the teeth chew the food and saliva starts breaking it down, so digestion begins here.
Q2 — Digestive System · easy · theory
After we swallow food, it is stored and churned in the muscular bag called the:
A. kidney
B. lungs
C. stomach ✓ Correct
D. heart
Solution: The stomach churns the food and mixes it with digestive juices.
Q3 — Digestive System · easy · theory
The watery liquid made in the mouth that helps soften food and start its digestion is:
A. blood
B. urine
C. saliva ✓ Correct
D. sweat
Solution: Saliva wets the food and begins breaking it down as we chew.
Q4 — Digestive System · easy · theory
The sharp front teeth used for biting and cutting food are called:
A. incisors ✓ Correct
B. canines
C. molars
D. wisdom teeth
Solution: Incisors are the flat, sharp front teeth used to cut and bite food.
Q5 — Respiratory System · easy · theory
Which gas from the air do we mainly take IN when we breathe?
A. Oxygen (O₂) ✓ Correct
B. Hydrogen
C. Nitrogen
D. Carbon dioxide (CO₂)
Solution: Our body needs oxygen (O₂), so we breathe it in from the air.
Q6 — Respiratory System · easy · theory
Which gas do we mainly give OUT when we breathe out?
A. Nitrogen
B. Carbon dioxide (CO₂) ✓ Correct
C. Oxygen (O₂)
D. Helium
Solution: Carbon dioxide (CO₂) is the body’s waste gas, and we breathe it out.
Q7 — Respiratory System · easy · theory
The pair of spongy organs in our chest that we use for breathing are the:
A. lungs ✓ Correct
B. ears
C. liver
D. kidneys
Solution: The two lungs take in air and pass oxygen into the blood.
Q8 — Respiratory System · easy · theory
We normally breathe in air through our:
A. nose ✓ Correct
B. eyes
C. skin
D. ears
Solution: Air enters the body through the nose, which cleans and warms it.
Q9 — Circulatory System · easy · theory
Which organ pumps blood to all parts of the body?
A. The lungs
B. The heart ✓ Correct
C. The stomach
D. The brain
Solution: The heart is a muscular pump that pushes blood around the whole body.
Q10 — Circulatory System · easy · theory
The red liquid that flows in our body, carrying food and oxygen, is:
A. urine
B. blood ✓ Correct
C. water
D. saliva
Solution: Blood carries oxygen and digested food to all parts of the body.
Q11 — Circulatory System · easy · theory
Blood flows all over the body inside tubes called:
A. food pipes
B. nerves
C. blood vessels ✓ Correct
D. bones
Solution: Blood vessels are the tubes that carry blood throughout the body.
Q12 — Circulatory System · easy · theory
Blood looks red because of the tiny:
A. red blood cells ✓ Correct
B. bones
C. air sacs
D. water drops
Solution: Red blood cells give blood its red colour and carry oxygen.
Q13 — Skeletal & Nervous Systems · easy · theory
The framework of all the bones that supports our body and gives it shape is called the:
A. skeleton ✓ Correct
B. muscle
C. blood
D. skin
Solution: The skeleton is the frame of bones that holds up and shapes the body.
Q14 — Skeletal & Nervous Systems · easy · theory
The set of bones that protects our brain is the:
A. rib cage
B. skull ✓ Correct
C. hip bone
D. backbone
Solution: The skull is a hard case of bone that protects the soft brain.
Q15 — Skeletal & Nervous Systems · easy · theory
The main organ that controls the whole body and helps us think is the:
A. lung
B. liver
C. heart
D. brain ✓ Correct
Solution: The brain is the control centre that lets us think, feel and move.
Q16 — Skeletal & Nervous Systems · easy · theory
The place where two bones meet and let us bend and move is called a:
A. vein
B. joint ✓ Correct
C. muscle
D. nerve
Solution: A joint is where bones meet, allowing movement such as bending the knee.
Q17 — Digestive System · hard · theory
Which shows the correct path that food follows through the body?
A. Stomach → mouth → small intestine → large intestine → food pipe
B. Mouth → stomach → food pipe → large intestine → small intestine
C. Mouth → windpipe → lungs → stomach → intestine
D. Mouth → food pipe → stomach → small intestine → large intestine ✓ Correct
Solution: Food travels mouth → food pipe → stomach → small intestine → large intestine.
Q18 — Digestive System · hard · theory
Bile made by the liver is stored in a small bag called the:
A. pancreas
B. appendix
C. gall bladder ✓ Correct
D. kidney
Solution: Bile is stored in the gall bladder until it is needed to digest fatty food.
Q19 — Respiratory System · hard · numerical
A boy breathes 20 times in one minute. How many times does he breathe in 3 minutes?
A. 200
B. 23
C. 60 ✓ Correct
D. 40
Solution: 20 breaths in each minute × 3 minutes = 60 breaths.
Q20 — Respiratory System · hard · theory
Why is it better to breathe in through the nose than through the mouth?
A. The nose adds germs to the air
B. The nose has no use in breathing
C. The nose makes the air colder
D. The nose cleans, warms and moistens the air ✓ Correct
Solution: The nose filters, warms and moistens the air before it reaches the lungs.
Q21 — Circulatory System · hard · theory
Blood carries oxygen and digested food to the body cells and carries away the waste gas:
A. nitrogen
B. carbon dioxide (CO₂) ✓ Correct
C. hydrogen
D. oxygen (O₂)
Solution: Body cells make carbon dioxide (CO₂) as waste, and blood carries it away.
Q22 — Circulatory System · hard · numerical
A girl’s heart beats 80 times in one minute. How many times will it beat in 2 minutes?
A. 160 ✓ Correct
B. 100
C. 82
D. 800
Solution: 80 beats in each minute × 2 minutes = 160 beats.
Q23 — Skeletal & Nervous Systems · hard · theory
Quickly pulling your hand away from a hot pan without thinking is an example of a:
A. reflex action ✓ Correct
B. dream
C. digestion
D. habit you learned
Solution: A reflex action is a fast, automatic response that protects the body.
Q24 — Skeletal & Nervous Systems · hard · theory
The shoulder joint lets your arm move round in almost all directions. This type of joint is a:
A. hinge joint
B. fixed joint
C. no joint at all
D. ball and socket joint ✓ Correct
Solution: A ball and socket joint, like the one at the shoulder, allows movement in all directions.
Q25 — Digestive System · medium · theory
Most of the digested food is absorbed into the blood through the walls of the:
A. mouth
B. small intestine ✓ Correct
C. stomach
D. food pipe
Solution: The small intestine has a very long inner wall through which digested food passes into the blood.
Q26 — Digestive System · medium · theory
The largest gland in the body, which makes bile to help digest fatty food, is the:
A. liver ✓ Correct
B. kidney
C. heart
D. lungs
Solution: The liver is the body’s largest gland, and its bile helps break down fats.
Q27 — Digestive System · medium · theory
Chewed food is pushed from the mouth down to the stomach through a tube called the:
A. windpipe
B. food pipe ✓ Correct
C. blood vessel
D. small intestine
Solution: The food pipe (oesophagus) carries swallowed food down to the stomach.
Q28 — Digestive System · medium · theory
What is the main job of the large intestine?
A. To make blood
B. To absorb water from the undigested food ✓ Correct
C. To breathe in air
D. To chew the food
Solution: The large intestine soaks up water from the leftover food, leaving solid waste behind.
Q29 — Respiratory System · medium · theory
Air travels from the nose down to the lungs through a tube called the:
A. blood vessel
B. food pipe
C. windpipe ✓ Correct
D. backbone
Solution: The windpipe (trachea) carries air from the nose down into the lungs.
Q30 — Respiratory System · medium · theory
The large dome-shaped muscle below the lungs that helps us breathe is the:
A. stomach
B. liver
C. heart
D. diaphragm ✓ Correct
Solution: The diaphragm moves down and up to pull air into the lungs and push it out.