Summary of "Biology | first term | transport in human 3 | blood | دكتور مصطفى خضر"

Key Concepts:

Blood Composition:
- Blood consists of plasma (54%), Red Blood Cells, White Blood Cells, and Platelets.
- Plasma is primarily composed of:
  - 90% water
  - 7% proteins (albumin, globulin, fibrinogen)
  - 1% organic salts
  - 2% other substances including enzymes and hormones.
Blood Characteristics:
- Normal pH of blood: 7.4
- Normal temperature of blood: 37°C
- Volume of blood in the human body: approximately 5 to 6 liters.
- Blood color varies based on oxygen content:
  - Bright red when oxygenated.
  - Dark red when deoxygenated.
Types of Blood Cells:
- Red Blood Cells (RBCs):
  - Produced in the bone marrow.
  - Approximately 4.5 million cells per cubic millimeter in males and slightly less in females.
  - Lifespan of about 120 days; die in the spleen, liver, or bone marrow.
  - Function: Transport oxygen (via hemoglobin) and carbon dioxide.
- White Blood Cells (WBCs):
  - Approximately 7,000 cells per cubic millimeter.
  - Lifespan of 13 to 20 days; also die in the spleen.
  - Function: Immune defense against pathogens.
- Platelets:
  - Approximately 250,000 cells per cubic millimeter.
  - Lifespan of about 10 days.
  - Function: Blood clotting.

Blood clotting is crucial for preventing blood loss from injuries. The process involves several factors:

Thromboplastin: Activates clotting factors.
Prothrombin: Converts to thrombin in the presence of calcium.
Fibrinogen: Converts to fibrin, forming a mesh that traps blood cells to create a clot.

Key factors influencing clotting include calcium levels and the presence of certain proteins.

Blood plays a role in maintaining homeostasis, regulating body temperature, pH, and nutrient levels.

Blood pressure is measured using a sphygmomanometer, indicating systolic (120) and diastolic (80) pressures.

This summary encapsulates the essential scientific information regarding blood transport and its functions as presented in the video.