- Blood volume: Adults have about 5-6 liters of blood (8% of body weight)
- Blood composition: 55% plasma, 45% blood cells
- Red blood cell count: 4.5-5.5 million per microliter
- Blood cell lifespan: Red cells 120 days, white cells hours to years
- Blood production: 200 billion new red blood cells made daily
- pH regulation: Blood maintains pH 7.35-7.45 (slightly alkaline)
This key facts covers Key Facts About Blood within Blood Components and Vessels for GCSE Biology. Blood composition, red and white blood cells, platelets, plasma, blood vessel structure and function, adaptations for transport It is section 7 of 16 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Blood Components and Vessels
What is the main function of red blood cells?
Explain how red blood cells are adapted for their function of transporting oxygen.
Quick recall flashcards
What is hemoglobin?
A protein in red blood cells containing iron that binds reversibly with oxygen to transport it around the body.
What are platelets?
Small cell fragments with no nucleus that help blood clot by sticking to damaged vessels and releasing clotting factors.