Histology

• Parasympathetic


  Fluid extracellular Material - Plasma
• Plasma


  Propelled by rhythmic contraction of the heart
• Preganglionic neuron


  Neurotransmitter released: Acetylcholine
• Postganglionic neuron


  Neurotransmitter released: Acetylcholine
• Sympathetic


  Preganglionic neuron: Neurotransmitter released: Acetylcholine
• Sympathetic


  Postganglionic neuron: Neurotransmitter released: Norepinephrine
• Exceptions for Sympathetic


  • Acetylcholine for sweat glands
  • Epinephrine for adrenal medulla
• Functions of Blood


  • Transport nutrients, oxygen, wastes, and carbon dioxide to and from the tissues
  • To convey hormones, cytokine, chemokines, and other soluble regulatory molecules
  • To transport leukocytes and antibodies through the tissues
  • To maintain homeostasis
• Plasma


  • 92% by weight: Water
  • 7% by weight: Proteins
  • 1% by weight: Other solutes
• Plasma Proteins


  • Albumins 58%
  • Globulins 37%
  • Fibrinogen 4%
  • Regulatory proteins <1%
• Buffy coat


  Less than 1% of whole blood
• Platelets


  150-400 thousand per cubic mm
• Leukocytes


  4.5-11 thousand per cubic mm
• Sympathetic Division


  • Preganglionic sympathetic nerves: Neuronal cell bodies in the thoracic and lumbar segments of the spinal cord
  • Sympathetic postganglionic neurons: Located in small ganglia along the vertebral column
• Parasympathetic Division


  • Preganglionic parasympathetic nerves: Neuronal cell bodies in the medulla and midbrain and in the sacral portion of the spinal cord
  • Parasympathetic postganglionic neurons: Found in very small ganglia always located near or within the effector organs
• Sympathetic: "Fight or flight" response is activated
• Parasympathetic: "Rest and digest" response is activated
• The amount of O2 in blood (the O2 pressure) is highest in arteries and lung capillaries and decreases in tissue capillaries, where exchange of O2 and CO2 occurs between blood and tissues
• Major Plasma Proteins


  • Albumin
  • Globulins
  • Immunoglobulins (antibodies or y-globulins)
  • Complement Proteins
  • Clotting Factors
  • Plasma Lipoproteins
• Albumin serves to maintain the osmotic pressure of the blood; transport insoluble metabolites
• Globulins (a- and B-) transport metal ions; protein-bound lipids, lipid-soluble vitamins
• Immunoglobulins (antibodies or y-globulins) are secreted by plasma cells; antibodies for host defense
• Complement Proteins comprise a defensive system important in inflammation and destruction of microorganisms
• Clotting Factors are involved in the formation of blood clots
• Plasma Lipoproteins transport triglycerides and cholesterol to/from the liver
• Electrolytes help establish and maintain membrane potentials, maintain pH balance, and regulate osmosis
• Nutrients provide an energy source and are precursors for synthesizing other molecules
• Respiratory gases (oxygen and carbon dioxide) are transported in the blood
• Waste products are transported in the blood to be removed by the liver and kidneys