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.
Topic position
Section 7 of 16
Practice
18 questions
Recall
24 flashcards
Key Facts About Blood
- 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)