Blood facts

Approximately 8% of an adult’s body weight is made up of blood.

Females have around 4-5 litres, while males have around 5-6 litres. This difference is mainly due to the differences in body size between men and women.

Its mean temperature is 100.4 degrees Fahrenheit.

It has a pH of 7.35-7.45, making it slightly basic (less than 7 is considered acidic).

Whole blood is about 4.5-5.5 times as viscous as water, indicating that it is more resistant to flow than water. This viscosity is vital to the function of blood because if blood flows too easily or with too much resistance, it can strain the heart and lead to severe cardiovascular problems.

Blood in the arteries is a brighter red than blood in the veins because of the higher levels of oxygen found in the arteries.