ScienceAges 13-15

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 13-15

Human body systems & organs

Take your time. Show your thinking.

1. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Heart · Lungs · Digestive Tract
2. 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
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Heart · Lungs · Digestive Tract
4. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Heart · Lungs · Digestive Tract
5. 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
6. Which component of blood defends the body against pathogens by engulfing microbes or producing antibodies: white blood cells or red blood cells?
Heart · Lungs · Digestive Tract
7. Which digestive enzyme breaks down fats and oils (lipids) into fatty acids and glycerol: lipase or amylase?
Heart · Lungs · Digestive Tract
8. Which nutrient group is primarily needed for building and repairing body cells and muscle tissue (found in fish, eggs, beans and lentils): proteins or water?
Heart · Lungs · Digestive Tract
9. 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
10. 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
11. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract
12. 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

12 questions · Seed 104729 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 13-15

Human body systems & organs

Answers and reasoning. Review before teaching.

1. 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.
2. 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.
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Capillaries
Thin capillary walls provide a short diffusion pathway between blood and cells.
4. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Small intestine
Villi and microvilli in the small intestine provide a huge surface area for nutrient absorption.
5. 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.
6. Which component of blood defends the body against pathogens by engulfing microbes or producing antibodies: white blood cells or red blood cells?
White blood cells
White blood cells (leukocytes) are key cells of the immune system.
7. Which digestive enzyme breaks down fats and oils (lipids) into fatty acids and glycerol: lipase or amylase?
Lipase
Lipase enzymes digest lipids into fatty acids and glycerol.
8. Which nutrient group is primarily needed for building and repairing body cells and muscle tissue (found in fish, eggs, beans and lentils): proteins or water?
Proteins
Proteins supply amino acids for growth and tissue repair.
9. 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.
10. 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.
11. 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.
12. 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.

12 questions · Seed 104729 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Human body systems & organs

Take your time. Show your thinking.

1. Which digestive enzyme breaks down large starch molecules into simple sugars: amylase or lipase?
Heart · Lungs · Digestive Tract
2. 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
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Heart · Lungs · Digestive Tract
4. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Heart · Lungs · Digestive Tract
5. 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
6. Which component of blood defends the body against pathogens by engulfing microbes or producing antibodies: white blood cells or red blood cells?
Heart · Lungs · Digestive Tract
7. Which digestive enzyme breaks down fats and oils (lipids) into fatty acids and glycerol: lipase or amylase?
Heart · Lungs · Digestive Tract
8. Which nutrient group is primarily needed for building and repairing body cells and muscle tissue (found in fish, eggs, beans and lentils): proteins or water?
Heart · Lungs · Digestive Tract
9. 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
10. 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
11. Which blood vessels carry blood BACK toward the heart and contain valves to prevent backflow: veins or arteries?
Heart · Lungs · Digestive Tract
12. 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

12 questions · Seed 104729 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Human body systems & organs

Answers and reasoning. Review before teaching.

1. 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.
2. 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.
3. Which microscopic blood vessels have walls only one cell thick to allow rapid exchange of oxygen, nutrients and waste with body tissues: capillaries or arteries?
Capillaries
Thin capillary walls provide a short diffusion pathway between blood and cells.
4. In which long, folded organ of the digestive system are most digested nutrients absorbed into the bloodstream through tiny finger-like villi: the small intestine or the oesophagus?
Small intestine
Villi and microvilli in the small intestine provide a huge surface area for nutrient absorption.
5. 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.
6. Which component of blood defends the body against pathogens by engulfing microbes or producing antibodies: white blood cells or red blood cells?
White blood cells
White blood cells (leukocytes) are key cells of the immune system.
7. Which digestive enzyme breaks down fats and oils (lipids) into fatty acids and glycerol: lipase or amylase?
Lipase
Lipase enzymes digest lipids into fatty acids and glycerol.
8. Which nutrient group is primarily needed for building and repairing body cells and muscle tissue (found in fish, eggs, beans and lentils): proteins or water?
Proteins
Proteins supply amino acids for growth and tissue repair.
9. 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.
10. 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.
11. 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.
12. 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.

12 questions · Seed 104729 · Age guidance, not curriculum certification