A&P Module 1

Characteristics of Blood

Viscosity, Temperature, PH, and Volume.

What causes blood to change color

Hemoglobin

• Bright red - Oxygenated

• Darker red - Released Oxygen

Viscosity

Thickness

• Great influence on blood flow and pressure.

  • More viscous = Greater resistance to flow.

  • 5x higher viscosity than water.

  • Sticky

Temperature

Slightly higher than normal body temperature.

• 100.4 F vs 98.6 F

• Due to the friction as it moves through vessels.

PH

A measure of contraction of hydrogen ions in a solution.

• 7 = Neutral

• 1 = Very Acidic

• 14 = Very Basic

• Blood ph = 7.35 - 7.45 of the average person

  • Slight basic

Volume

• About 8% of adult body weight

  • Adult males = 5 - 6L

  • Adult females = 4 - 5L

Functions of Blood

• Bring Nutrients from the digestive tract to the liver → Into bloodstream, deliver to cells.

• Bring Oxygen from lungs into bloodstream → Deliver to cells.

• Deliver Hormones to cellular targets throughout the body.

• Homeostasis:

  • Body temperature - Negative feedback loop

  • Heat - Blood circulates to skin surface

  • Cold - Blood diverted away from skin surface

    • Maintains warmer core.

    • Reduction of heat loss.

Blood Defense

There are specialized proteins that stop loss of blood.

• Leukocytes also help.

Components of Blood

Made up of Formed Elements and a fluid extracellular matrix.

Formed Elements

Cellular elements, including: Erythrocytes, Leukocytes, Thrombocytes, and Plasma.

Blood

A fluid connective tissue.

Erythocytes

Red blood cells

• Essential for the transport of oxygen in the blood.

Leukocytes

White blood cells

• They attack pathogens and diseased cells.

Thrombocytes

Platelets

• They contain enzymes and other substances important for clotting.

Plasma

Extracellular matrix

• Makes blood unique among connective tissues because it is fluid

  • It is mostly water.

  • Suspends the Formed Elements and enables them to circulate throughout the body within the cardiovascular system.