Understanding Blood: Functions, Composition, and Importance

Overview

Blood, a red fluid circulating in blood vessels, is essential for life.
Discussion includes what gives blood its color, its functions, and how it's made.
Connection between blood and fitness/athletic performance.

Liquid Connective Tissue: Blood is composed of cells suspended in an extracellular matrix (plasma).
Related Fluids: Lymphatic fluid, cerebrospinal fluid, and interstitial fluid are all derived from blood.

Oxygen and Carbon Dioxide: Transports oxygen from lungs to cells and CO2 back to lungs for exhalation.
Nutrients: Carries nutrients from the GI tract to cells.
Hormones and Waste: Delivers hormones and transports waste products to the lungs, kidneys, and skin for elimination.

Homeostasis: Maintains pH, thermal regulation (sweating), and osmotic pressure influencing water content in cells and blood vessels.

Clotting: Prevents excessive blood loss after injury.
Immune Defense: White blood cells and proteins protect against disease through phagocytosis and antibodies.

Viscosity: Denser and more viscous than water.
Temperature: Around 38°C (100.4°F).
pH: Slightly alkaline (7.35 to 7.45).
Color: Bright red when oxygenated, dark red/purplish when deoxygenated.
Volume: 5-6 liters in adults (males), 4-5 liters (females).
Impact of Exercise: Increased blood volume through plasma and additional red blood cells with cardiovascular exercise.

Impact: Poor oral health (gum disease) can lead to cardiovascular conditions such as endocarditis and other cardiovascular diseases.
Example: Bacteria from the mouth entering the bloodstream.

Plasma
- Straw-colored liquid making up 55% of blood.
- Composed of 91.5% water, 7% proteins, and 1.5% solutes.
- Proteins: Albumin (transports substances, influences viscosity), Globulins (attack viruses/bacteria), Fibrinogen (clotting).
- Solutes: Electrolytes, nutrients, gases, hormones, waste products.
Formed Elements
- 45% of blood: Red blood cells (erythrocytes), White blood cells (leukocytes), Platelets (thrombocytes).
- Production: Made in red bone marrow (hematopoiesis).

Production: 2-3 million produced per second, 200 billion per day.
Function: Carry oxygen to tissues using hemoglobin (280 million molecules per cell, each carrying 4 oxygen molecules).
Structure: Strong, flexible membrane; no nucleus; bioconcave shape for efficient gas exchange.

Types: Iron deficiency, Vitamin B12/Folate deficiency, Hemorrhagic (due to menstrual bleeding).
Impact: Reduced oxygen-carrying capacity of blood.

Function: Protect against infections and foreign invaders. Different types with specific functions (e.g., fighting bacteria, viruses, allergies).

Role in Clotting: Form platelet plugs and blood clots to prevent blood loss and aid wound repair.

Blood is critical for transportation, regulation, and protection within the body.
Importance of maintaining healthy blood volume and quality through diet, exercise, and oral hygiene.
Stay tuned for further discussions on related topics such as the effect of elevation on red blood cell count.