Blood composition LO8

Question 1

Blood

Answer 1

Fluid connective tissue composed of
- plasma
- Leukocytes (WBC)
- Erythrocytes (RBC)
- Platelets

Question 2

Erythrocytes (RBC)

Answer 2

Structural characteristics
- Biconcave shape
- Huge SA:V (fill up with oxygen)
- Ability to bend and flex
Function
- respiratory gas transport
- Hb binds reversibly with oxygen and carbon dioxide

Question 3

Haemoglobin (Hb)

Answer 3

• binds 4 oxygens
• facilitate effective gas transport

Question 3

Regulation of erythropoiesis

Answer 3

Blood cell numbers are under strict homeostatic regulation:
- RBC are produced within the bone marrow (erythropoiesis)
- Too few RBC –> tissue hypoxia (insufficient O2)

Question 4

Leukocytes (WBC)

Answer 4

• Formed in the bone marrow
• Primary function is defence
• Neutrophils & monocytes: Able to leave the blood vessels and move into the tissues to sites of tissue damage or infection
• Phagocytes: cells able to engulf
  and destroy damaged and dead cells, and invaders
• Lymphocytes: Crucial for specific immunity e.g.
  antibody production

Question 5

Functions of blood

Answer 5

Distribution - oxygen, nutrients, metabolic waste, hormones
Regulation - pH, fluid volume, temp, composition of ICF
Protection - infection, (WBC, Lymphocytes), preventing blood loss (platelets)