Understanding Why Blood is Red

The video explains why blood is red, focusing on the role of red blood cells. These cells transport oxygen using a molecule containing iron, which gives blood its color. When oxygen is picked up, the molecule changes shape, turning the blood bright red. As blood circulates and delivers oxygen, it becomes dull again. This process highlights the dynamic nature of blood color and its essential role in the human body.

What is one of the main functions of red blood cells?

• To produce hormones

• To digest food

• To fight infections

• To transport oxygen

What special molecule do red blood cells use to carry oxygen?

• Insulin

• Hemoglobin

• Chlorophyll

• Glucose

What element in the molecule gives blood its dark red color?

• Calcium

• Copper

• Iron

• Zinc

How does the color of blood change when it is full of oxygen?

• It turns blue

• It becomes bright red

• It turns green

• It becomes yellow

What happens to the color of blood as it delivers oxygen throughout the body?

• It becomes dull again

• It becomes brighter

• It turns white

• It turns black