The diaphragm relaxes when you inhale.

The foetus develops inside the oviduct

White blood cells help fight infections

Gas exchange takes place in the alveoli.

What is the main function of plateles

Smoking improves the efficiency of gas exchange

Fertilisation usually occurs in the oviduct

Plasma Is the liquid part of blood

The trachea has cartilage rings to keep it open

Which gas is required for aerobic respiration

After fertilisation, the zygote instantly becomes a fetus.

Ovaries produce eggs

The placenta supplies nutrients and oxygen to the fetus

The pulmonary artery carries oxygen-rich blood.

Capillaries have thin walls for diffusion

What carries oxygen in red blood cells?

The pulmonary vein carries oxygen-poor blood.

Exercise increases heart rate because muscles need more oxygen.

The uterus is where the fetus develops.

What structure produces sperm in males?

Hormones help control changes during puberty.

The cervix is the site where fertilisation happens.

Carbon dioxide moves from the blood into the alveoli during exhalation.

Aerobic respiration releases carbon dioxide and water.

The left side of the heart pumps oxygenated blood to the body.

Capillaries have thick walls to handle high pressure.

Which blood vessel carries oxygen-poor blood from the heart to the lungs

The pulmonary vein carries oxygen-poor blood.

Damaged alveoli reduce gas exchange efficiency.

Which structure helps remove waste products from the fetus?

Breathing out is called exhalation.

The alveoli have a large surface area to speed up gas exchange

Valves prevent blood from flowing backward.

The trachea carries food to the stomach.

Hormones help control changes during puberty.

Bronchi are air tubes that branch from the trachea.

Veins always carry oxygen-rich blood.

Blood is pumped through the body only by veins.

The diaphragm relaxes during exhalation.