Physiology Blood (obj. 1)

Cardio Vascular system

• The cardiovascular system is a system of rapid

transport

• Blood is the transporter

• Of things like cells, gases, nutrients/wastes, heat, and

hormones

• The heart • Blood vessels provides locomotion for blood by pumping

provide the pathways for blood

PLASMA (LIQUID)

• 55% of whole blood

• 92% of plasma is water

• Various solutes and proteins dissolved in that water

FORMED ELEMENTS (CELLS)

• 45% of whole blood

• 99.9% of formed elements are red blood cells

• The rest are white blood cells and platelets

RED BLOOD CELLS

• Main property is to carry/transport oxygen

• Q: what do we like oxygen for again?

• Shaped to load/unload effectively

• Ejects all organelles during development, to make as much

as possible

room for hemoglobin • Lives only around 120 days

HEMOGLOBIN

• Protein that makes up 95% of a red blood cell

• Two significant components:

• Heme – a red pigment

• Iron – attachment site for oxygen

ANEMIA

• Many types/causes, but characterized by a lack of healthy RBC’s

• Less RBC’s means less oxygen, which means less energy

or vitamin deficiency

stems from a genetic condition which results in an

abnormal shape for hemoglobin, and thus the RBC

• Often due to iron • Sickle Cell Anemia • Main symptoms include fatigue, weakness, pale skin, cold

hands/feet, and more

WHITE BLOOD CELLS

• Main function is for defense

Five major varieties:

1. Neutrophils

• Most abundant (numerous)

• First responders

• Phagocytic (meaning they engulf pathogens)

• Targets bacteria and fungi

• Die after little activity (eventually forming pus) 2. Eosinophils

• Secretes chemicals that destroy parasitic infections

• Can reach membranes outside of the bloodstream

• Has a presence in allergic reactions

3. Basophils

• Secretes a variety of chemicals, most notably histamine

• Histamine’s main function is to dilates blood vessels, but has a strong

presence in allergy-related inflammation

4. Monocytes

• Large in size, and phagocytic

• Helps with “immune memory”

• Can migrate into tissues to remove debris or fight pathogens

5. Lymphocytes

• Wide variety of different types that have specific uses

• The immune

BLOOD CELL PRODUCTION

• Hematopoiesis is the production of new blood cells

• Specific stem cells reside in our bone marrow

• Copies of the stem cells are made, and the copies will either:

• Remain as stem cells to maintain supply

• Become one of the different blood cells and sent to the bloodstream • Production rate for RBC’s specifically is controlled by a hormone called

EPO, which is produced by the kidneys

• The more EPO, the more blood cells are produced

LEUKEMIA(S)

• A family of cancers that revolve around stem cells in the bone marrow

making the wrong types of cells and/or the wrong amount of cells

• Having the wrong blood cells can lead to bone pain, fatigue, fever, and

bruising, among other things

• Newer treatments include stem cell transplants (PBSCT)

PLATELETS

The smallest formed elements in our blood, they play a large

role in hemostasis, or blood clotting

HEMOSTASIS

1. Vascular Phase

   • In response to injury, the injured vessel will constrict at the injury site, decreasing the amount of blood flow/blood loss

   • The cells of the blood vessel injury site become “sticky”

2. Platelet Phase

   • Platelets that happen to flow past the sticky areas get stuck

   • Those platelets themselves then become sticky

   • Platelets accumulate and plug up the hole (platelet plug)

3. Coagulation Phase

*Clotting factors are a group of chemicals involved in blood clotting

• Extrinsic Pathway – the damaged blood vessel cells release clotting factors into bloodstream

• Intrinsic Pathway – the stuck platelets release clotting factors into bloodstream

• Common Pathway – in this new setting, clotting factors create a chain reaction resulting in the formation of a fibrin mesh that seals the injury

  • Aka a blood clot Coagulation Phase

  *Clotting factors are a group of chemicals involved in blood clotting

  • Extrinsic Pathway – the damaged blood vessel cells release clotting factors into bloodstream

  • Intrinsic Pathway – the stuck platelets release clotting factors into bloodstream

  • Common Pathway – in this new setting, clotting factors create a chain reaction resulting in the formation of a fibrin mesh that seals the injury

    • Aka a blood clot

BLOOD TYPE

• Based on 2 components:

  • The antigen present on the outside of RBC’s (think identification)

  • The antibody present in blood plasma (think roaming security)

• Blood type doesn’t mean anything as far as function, but does play a massive role in blood donation