ScienceAges 10-12

Human body systems & organs

Connect major human organs and systems to digestion, circulation, respiration and coordination. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 10-12

Human body systems & organs

Take your time. Show your thinking.

1. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Heart · Lungs · Digestive Tract
2. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract
3. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
Heart · Lungs · Digestive Tract
4. In the human circulatory system, which blood vessels carry blood AWAY from the heart under high pressure with thick muscular walls: arteries or veins?
Heart · Lungs · Digestive Tract
5. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
Heart · Lungs · Digestive Tract
6. Which organ produces bile (stored in the gallbladder) to neutralise stomach acid and emulsify fats into tiny droplets: the liver or the lungs?
Heart · Lungs · Digestive Tract
7. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Heart · Lungs · Digestive Tract
8. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Heart · Lungs · Digestive Tract
9. Which tiny cell fragments in blood help form clots at a wound to stop bleeding: platelets or red blood cells?
Heart · Lungs · Digestive Tract
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Heart · Lungs · Digestive Tract
11. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Heart · Lungs · Digestive Tract
12. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Heart · Lungs · Digestive Tract

12 questions · Seed 104731 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 10-12

Human body systems & organs

Answers and reasoning. Review before teaching.

1. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Alveoli
Millions of alveoli in the lungs provide a large moist surface area surrounded by capillaries for gas exchange.
2. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Veins
Veins operate at lower pressure and use one-way valves to keep blood flowing toward the heart.
3. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
It keeps food moving smoothly through the intestines
Fibre adds bulk to aid peristalsis and prevent constipation.
4. In the human circulatory system, which blood vessels carry blood AWAY from the heart under high pressure with thick muscular walls: arteries or veins?
Arteries
Arteries have thick elastic and muscular walls to withstand high-pressure blood pumped from the heart.
5. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
To absorb remaining water from undigested food waste
The large intestine reabsorbs water and electrolytes, leaving semi-solid faeces.
6. Which organ produces bile (stored in the gallbladder) to neutralise stomach acid and emulsify fats into tiny droplets: the liver or the lungs?
Liver
The liver secretes alkaline bile, which emulsifies lipids to increase surface area for lipase enzymes.
7. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Oesophagus (gullet)
Peristalsis in the oesophagus pushes the food bolus into the stomach.
8. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Carbohydrates
Carbohydrates are broken down into glucose, the main fuel for cellular respiration.
9. Which tiny cell fragments in blood help form clots at a wound to stop bleeding: platelets or red blood cells?
Platelets
Platelets trigger blood clotting to seal damaged vessels.
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Proteases
Proteases (such as pepsin and trypsin) hydrolyse proteins into amino acids.
11. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Diaphragm
Contraction of the diaphragm and intercostal muscles expands the thorax, lowering pressure so air flows into the lungs.
12. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Amylase
Carbohydrases such as amylase catalyse the breakdown of starch into sugars.

12 questions · Seed 104731 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 10-12

Human body systems & organs

Take your time. Show your thinking.

1. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Heart · Lungs · Digestive Tract
2. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract
3. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
Heart · Lungs · Digestive Tract
4. In the human circulatory system, which blood vessels carry blood AWAY from the heart under high pressure with thick muscular walls: arteries or veins?
Heart · Lungs · Digestive Tract
5. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
Heart · Lungs · Digestive Tract
6. Which organ produces bile (stored in the gallbladder) to neutralise stomach acid and emulsify fats into tiny droplets: the liver or the lungs?
Heart · Lungs · Digestive Tract
7. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Heart · Lungs · Digestive Tract
8. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Heart · Lungs · Digestive Tract
9. Which tiny cell fragments in blood help form clots at a wound to stop bleeding: platelets or red blood cells?
Heart · Lungs · Digestive Tract
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Heart · Lungs · Digestive Tract
11. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Heart · Lungs · Digestive Tract
12. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Heart · Lungs · Digestive Tract

12 questions · Seed 104731 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 10-12

Human body systems & organs

Answers and reasoning. Review before teaching.

1. What are the tiny air sacs in the lungs where oxygen diffuses into the blood and carbon dioxide diffuses out: alveoli or villi?
Alveoli
Millions of alveoli in the lungs provide a large moist surface area surrounded by capillaries for gas exchange.
2. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Veins
Veins operate at lower pressure and use one-way valves to keep blood flowing toward the heart.
3. Why is dietary fibre (roughage from vegetables, fruits and whole grains) important even though humans cannot digest it: it keeps food moving smoothly through the intestines, or it turns into bone?
It keeps food moving smoothly through the intestines
Fibre adds bulk to aid peristalsis and prevent constipation.
4. In the human circulatory system, which blood vessels carry blood AWAY from the heart under high pressure with thick muscular walls: arteries or veins?
Arteries
Arteries have thick elastic and muscular walls to withstand high-pressure blood pumped from the heart.
5. What is the main function of the large intestine (colon): to absorb remaining water from undigested food waste, or to pump blood?
To absorb remaining water from undigested food waste
The large intestine reabsorbs water and electrolytes, leaving semi-solid faeces.
6. Which organ produces bile (stored in the gallbladder) to neutralise stomach acid and emulsify fats into tiny droplets: the liver or the lungs?
Liver
The liver secretes alkaline bile, which emulsifies lipids to increase surface area for lipase enzymes.
7. Which muscular tube carries swallowed food from the mouth down to the stomach by wave-like contractions (peristalsis): the oesophagus (gullet) or the trachea (windpipe)?
Oesophagus (gullet)
Peristalsis in the oesophagus pushes the food bolus into the stomach.
8. Which nutrient group serves as the body’s primary fuel for cellular respiration (found in rice, bread, pasta and fruit): carbohydrates or minerals?
Carbohydrates
Carbohydrates are broken down into glucose, the main fuel for cellular respiration.
9. Which tiny cell fragments in blood help form clots at a wound to stop bleeding: platelets or red blood cells?
Platelets
Platelets trigger blood clotting to seal damaged vessels.
10. Which class of digestive enzymes breaks down proteins into amino acids: proteases or amylases?
Proteases
Proteases (such as pepsin and trypsin) hydrolyse proteins into amino acids.
11. Which dome-shaped muscle beneath the lungs contracts and flattens when you inhale, increasing chest volume and drawing air in: the diaphragm or the bicep?
Diaphragm
Contraction of the diaphragm and intercostal muscles expands the thorax, lowering pressure so air flows into the lungs.
12. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Amylase
Carbohydrases such as amylase catalyse the breakdown of starch into sugars.

12 questions · Seed 104731 · Age guidance, not curriculum certification