L3.1: Plasma

• PLASMA

  ● 90% water; straw-colored fluid

  ● Includes dissolved substances

  ○ Nutrients

  ○ Salts (electrolytes)

  ○ Respiratory gases

  ○ Hormones

  ○ Plasma proteins

  ○ Waste products
• PLASMA

  ● Helps distribute heat

  ● Its composition varies continuously as cells exchange substances with the blood

  ○ Liver makes more proteins when levels drop

  ○ Respiratory and urinary systems restore blood pH to normal when blood becomes too acidic (acidosis) or alkaline (alkalosis)
• PLASMA PROTEINS

  ● Most abundant solutes in plasma

  ● Most are made by the liver (except for antibodies and protein-based hormones)
• PLASMA PROTEINS

  ● Examples:

  ○ ALBUMIN — an important blood buffer and contributes to osmotic pressure

  ○ CLOTTING PROTEINS — help to stem blood loss when a blood vessel is injured

  ○ ANTIBODIES — help protect the body from pathogens