Canada Grade 8 Science Human body systems

Which system in the human body is responsible for transporting blood, nutrients, and waste products?

• Respiratory system

• Circulatory system

• Digestive system

• Nervous system

Answer explanation

The circulatory system is responsible for transporting blood, nutrients, and waste products throughout the body, making it the correct choice. The other systems listed have different primary functions.

What is the primary function of the respiratory system?

• To break down food

• To circulate blood

• To exchange gases

• To protect the body

Answer explanation

The primary function of the respiratory system is to exchange gases, specifically oxygen and carbon dioxide, between the body and the environment. This process is essential for cellular respiration and overall metabolic function.

Which organ is primarily responsible for the absorption of nutrients in the digestive system?

• Stomach

• Large intestine

• Small intestine

• Liver

Answer explanation

The small intestine is the primary organ for nutrient absorption in the digestive system, as it has a large surface area and specialized structures that facilitate the uptake of nutrients from digested food.

What is the main component of blood that carries oxygen to the body's cells?

• White blood cells

• Platelets

• Plasma

• Red blood cells

Answer explanation

Red blood cells are the main component of blood responsible for carrying oxygen to the body's cells. They contain hemoglobin, which binds to oxygen, allowing efficient transport throughout the body.

Which part of the respiratory system is also known as the windpipe?

• Bronchi

• Trachea

• Larynx

• Alveoli

Answer explanation

The trachea, commonly known as the windpipe, is the tube that connects the larynx to the bronchi, allowing air to pass to and from the lungs. It is distinct from the bronchi, larynx, and alveoli.

What is the role of the diaphragm in the respiratory system?

• To filter air

• To produce sound

• To aid in breathing

• To protect the lungs

Answer explanation

The diaphragm is a muscle that contracts and relaxes to help expand and compress the lungs, facilitating breathing. Therefore, its primary role in the respiratory system is to aid in breathing.

Which organ in the circulatory system is responsible for pumping blood throughout the body?

• Lungs

• Heart

• Liver

• Kidneys

Answer explanation

The heart is the organ responsible for pumping blood throughout the body, supplying oxygen and nutrients to tissues while removing waste products. The other options, like lungs and liver, have different functions.

What is the primary function of the digestive system?

• To protect the body from infection

• To break down food and absorb nutrients

• To circulate blood

• To exchange gases

Answer explanation

The primary function of the digestive system is to break down food and absorb nutrients, which is essential for providing energy and maintaining bodily functions.

Which blood vessels carry blood away from the heart?

• Veins

• Arteries

• Capillaries

• Lymph vessels

Answer explanation

Arteries are the blood vessels that carry blood away from the heart to the rest of the body. In contrast, veins carry blood back to the heart, and capillaries are small vessels where gas exchange occurs.

What is the function of the alveoli in the respiratory system?

• To filter air

• To exchange oxygen and carbon dioxide

• To produce mucus

• To support the trachea

Answer explanation

The alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide occurs. This process is essential for respiration, making 'to exchange oxygen and carbon dioxide' the correct function of the alveoli.

Tags

NGSS.MS-LS1-3