test one Flashcards
function of blood
- Transport: O2, CO2, nutrients, hormones, wastes
- Regulates: pH and ion compositions by absorbing and neutralizing acids
3, Restricts: Fluid loss at injury sites with clotting process - Defends: against toxins and pathogens with WBC and antibodies
- Stabilizes: temp by absorbing heart and distributing blood flow to different areas
Red blood cells/Erythrocytes function
- Transport of respiratory gasses (O2 & CO2)
- RBCs play an important role in homeostasis of acids — Base balance `
Red blood cell sizes
Normocytes: normal cell size
Microcytic: small cell size
Macrocytic: large cell size
Hemoglobin content
Normochromic: normal Hb content
Hypochromic: low Hb content
HyperchromicL high Hb content
What blood cells/leukocytes (WBC)
- Less than 1% of all blood cells
- Larger than RBCs
- Helps the body defend against pathogens
- Removes toxins, wastes, and abnormal or damaged cells
- Contains a nucleus unlike a RBC
- Lacks hemoglobin
- Circulates for a short portion of lifespan (about 20 days)
- some WBCs leave the bloodstream and migrate through other tissues of the body
- Some remain in the tissues outside the bloodstream
Types of WBCs
Neutrophils, Eosinophils, Basophils, Monocytes: These are apart of the bodies nonspecific defences, responds to ant threat, without having to identify specific pathogens.
Lymphocytes: Respond to any threat, without having to identify specific pathogens .
To remember the size from largest to smallest of WBCa remember..
Never Let Monkeys Eat Bananas
Palates thrombocytes/megakaryocytes
One of the formed elected officials the blood
Specialized cell fragments in the body that pay a major role in blood clotting
Has no nucleus and is about half the size of RBCs
Lifespan: of about 9-12 days, and is removed by phagocytosis primarily in the spleen
Blood plasma
Liquids protein of whole blood
contains no formed elements
Transports organic and inorganic molecules
3% of total O2 transported in blood
5% of total CO2 transported in blood
composition
Water (92%) containing many dissolved substances including:
plasma proteins (7%)
other solutes (1% nutrients, Electrolytes, organic wastes)
3 major types of plasma proteins
- Albumins: Most abundant (about 60% of all plasma proteins)
- globulins: About 35% of plasma proteins, acts as transport proteins and antibodies or immunoglobulins. Globulins involved liopid transport called lipoprotein.
- Fibrinogen: About 4% of plasma proteins, function in blood clotting as insoluble strands of fibrin.
Blood is divided into two fractions (assuming 5.0L total)
- Plasma: extracellular part of blood: Liquide component 2.75 L (55%)
- Formed elements: Contains the cellular components (RBC, WBC, Platelets) 2.25L (45%)
Blood volumes in the body
Adult males average about 5-6 L of blood
Adult females average about 4-5 L of blood
Varies by average body size
Blood pH
Blood is alkaline — pH 7.35 to pH 7.45
If blood moves towards neutral you can become very sick “acidosis**
Blood lifespan
The average RBC lifespan is 120 days
Storage of donated blood is limited to 6 weeks
RBC formation
- Also called erythropoiesis
- In adults, it occurs in red bone marrow or myeloid tissue
- Requires amino acids =, iron, vitamins, vitamin B12 absorption requires intrinsic factor
- In adults, red bone marrow is found in vertebrae, sternum, ribs, scapulae, pelvis, proximal limb bones
Stem cells
Formed elements develop in red bone marrow
Process is hematopoiesis
Multi potent stem cell is a hemocytoblast
Division of a hemocytoblast produces 2 types of stem sells
1. lymphoid stem cell
2. Myeloid stem cell
Stem cell paths
Lymphoid stem cells develop into lymphocytes. some stem cells remain in red bone marrow; others migrate to lymphoid tissues
myeloid stem cells develop into all other formed elements
Hormones released by activated lymphocytes and other cells in immune response
Mechanisms of blood disease
Most blood diseases result from failure of myeloid and lymphatic tissues, where the formed elements are made.
Possible causes:
Toxic chemicals
radiation
inherited defects
nutritional deficiencies
cancer, including leukaemia
Jaundice
Yellowish skin and eyes
- Sgin of excessive level of bilirubin in blood
- Bilirubin level rise in peripheral tissues
Result of blocked bile ducts, due to: gallstones, failure of liver to absorb or excrete bilirubin. Hemolytic anemia, which involves excess RBC breakdown
Polycthemia
Increased RBCs
Anemia
Results in decreased tissue O2 levels
Decreased RBC
Deceased hemoglobin
Majority of clinical signs of anemia related to low tissue oxygen levels, Fatigue; skin pallor, Weakness; faintness; headache
Compensation by increasing heart and respiratory rates
How blood clotting works
- Blood vessel is damage causes platelets to become sticky and forms a “platelet plug” at the site of injury
- Accumulated platelets resales clotting factors that enter into the clotting mechanism
- Platelets ultimately become part of the blood clot itself
Homeostasis
the stopping of bleeding
- Halts the loaf of blood through damaged vessels
- Establishes framework for tissue repair
3 steps
1. Vascular phase — Vessel soak
2. Platelet phase — form platelet plug
3. coagulation phase — complex cascade
Requirements for blood clotting
- Calcium ions, vitamin K, and 11 different plasma proteins
- Liver synthesizes most of these clotting proteins
blood clot disorders
Thrombocytopenia = reduced platelet cont that is characterized by bleeding from small blood vessels
Thrombocytosis = High platelet count
Hemophilia = Bleeding disease
