Blood and Blood Vessels Flashcards
Transports everything that must be carried from one place to another
Blood
Only fluid tissue in the human body
Blood
Blood is also known as the?
“River of Life”
Components of blood
- Formed elements (living cells) 45%
- Plasma (nonliving fluid matrix) 55%
Thin, whitish layer between the erythrocytes and plasma
Buffy coat
Contains leukocytes and platelets (less than 1 percent of blood)
Buffy coat
What happens when blood is separated?
- Erythrocytes sink to the bottom
- Buffy coat in between, which is a thin, whitish layer
- Plasma rises to the top
Erythrocytes is 45 percent of blood, and this percentage is known as?
Hematocrit
- Sticky, opaque fluid
- Heavier and thicker than water
Blood
What color is oxygen-rich blood?
Scarlet red
What color is oxygen-poor blood?
Dull red or purple
________ is metallic and has a salty taste, often found in ________
Blood; children
Blood pH is slightly ________, between ____ and ____
Alkaline; 7.35 and 7.45
Blood temperature is slightly higher than body temperature because?
Cause of friction produced as blood flows through the vessels
Temperature of blood pH
38 degrees Celsius or 100.4 degrees Fahrenheit
Blood accounts for approximately ____% of body weight
8%
Blood volume in healthy adults is ___ to ____ liters, or about _____ quarts
5 to 6; 6
It is the liquid part of the blood, straw-colored fluid
Plasma
Plasma is approximately ____% water
90%
Over 100 different substances are dissolved in plasma; some examples are:
- Nutrients
- Salts (electrolytes)
- Respiratory gases
- Hormones
- Plasma proteins
- Various wastes and products of cell metabolism
Most abundant solutes in plasma
Plasma proteins
Except for antibodies and protein-based hormones, what makes the most plasma proteins?
Liver
Acts as a carrier to shuttle certain molecules through circulation, is an important blood buffer and contributes to osmotic pressure, helps keep water in bloodstream
Albumin
Help to stem blood loss when a blood vessel is injured
Clotting proteins
Help protect the body from pathogens
Antibodies
When blood drops to undesirable levels, the ____ is stimulated to make more proteins
Liver
When the blood becomes too acidic or too basic, both the ____ system and ____ system are called into action to restore it to its normal alkaline pH range of 7.35 to 7.45
Urinary and Respiratory
- Most abundant living cell in the blood
- Functions to carry oxygen
- Differs from other blood cells
Erythrocytes
What makes RBCs different from other blood cells?
- Anucleate
- Contain few organelles; lack mitochondira
- Essentially bags of hemoglobin
- Normal count is 5 million RBCs per cubic millimeter of blood
Homeostatic Imbalance of RBCs: Decrease in oxygen-carrying ability of blood
Anemia
Homeostatic Imbalance of RBCs: Disorder resulting from excessive or abnormal increase of RBCs
Polycythemia
- Crucial in body defense against diseases
- Complete cells, with nucleus and organelles
- Able to move into and out of blood vessels (diapedesis)
- Respond to chemicals released by damaged tissues
- Move by amoeboid motion
- 4800 to 10800 WBCs per mm³ of blood
Leukocytes
Homeostatic Imbalance of Leukocytes:
- WBC count above 11,000 cells per mm³ of blood
- Generally indicates an infection
Leukocytosis
Homeostatic Imbalance of Leukocytes:
- Abnormally low WBC count
- Commonly caused by certain drugs, such as corticosteroids and anticancer agents
Leukopenia
Homeostatic Imbalance of Leukocytes:
- Bone marrow becomes cancerous
- Numerous immature WBC are produced that tend to crowd: RBC that affects the supply of oxygen, platelets when there is damage, and normal WBC to fight infection
Leukemia
What are the types of Leukocytes?
- Granulocytes
- Agranulocytes
- Cytoplasmic granules can be stained
- Possess lobed nuclei
- Include neutrophils, eosinophils, and basophils
Granulocytes
- Lack of visible cytoplasmic granules
- Nuclei are spherical, oval, or kidney-shaped
- Include monocytes and lymphocytes
Agranulocytes
Name the WBCs from most to least abundant
Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils
Most numerous WBC
Neutrophils
- Multilobed nucleus
- Cytoplasm stains pink and contains fine granules
- Function as phagocytes at active sites of infection
- Numbers increase during infection
- 3,000 to 7,000 neutrophils per mm³ of blood.
Neutrophils
- Bilobed nucleus
- Nucleus stains blue-red
- Brick-red cytoplasmic granules
- Function is to kill parasitic worms and play a role in allergy attacks
- 100 to 400 eosinophils per mm³ of blood
Eosinophils
Rarest WBC
Basophils
- Multilobed nucleus that contains round, prominent granules
- Large histamine-containing granules that stain dark blue
- Presence can be an indication of severe allergic reaction
- Contain heparin
- 20 to 50 basophils per mm³ of blood
Basophils
- Strictly larger than RBCs
- Large, dark purple nucleus
- Reside in lymphatic tissues
- Plays a role in immune response
Lymphocytes
Produces antibodies
B-cells
Fight foreign invaders
T-cells
- Largest of the WBCs
- Distinctive U or kidney-shaped nucleus
- Function as macrophages when they migrate into tissues
- Important in fighting chronic infection
- 100-700 monocytes per mm³ of blood
Monocytes
- Fragments of megakaryocytes
- Needed for the clotting process
- Normal platelet count is 300,000 platelets per mm³ of blood
Thrombocytes
Homeostatic Imbalance of Thrombocytes:
- Sudden decrease in the platelet count in the blood
- Caused by too much consumption of alcohol, bone marrow disease, drugs used for cancer therapy
Thrombocytopenia
Homeostatic Imbalance of Thrombocytes:
- Increase in the number of platelets that an infection can cause
Thrombocytosis
The increase in number of platelets is unknown
Thrombocytosis
- Occurs in red bone marrow or myeloid tissue
- All the formed elements arise from a common stem cells, a hemocytoblast
Hematopoiesis
RBCs wear out in?
100 to 120 days
When worn out, what happens to RBCs?
Eliminated by phagocytes in the spleen or liver
What happens to the Hb of worn out RBCs?
Recycled
The formation of new RBCs depends on?
Division of hemocytoblast
Formation of new RBCs depends on division of hemocytoblast, usually controlled by what hormone produced by the kidney?
Erythropoietin
Formation of WBC and Platelets is controlled by?
Hormones
Prompt bone marrow to generate leukocytes
Colony stimulating factors (CSFs) and interleukins
Stimulates production of platelets from megakaryocytes
Thrombopoietin
Process of stopping the bleeding that results from a break in a blood vessel
Hemostasis
3 phases of hemostasis
- Vascular spasms
- Platelet plug formation
- Coagulation
Immediate response to blood vessel injury is vasoconstriction, causing blood vessel spasms
Vascular spasms
- Collagen fibers are exposed; platelets adhere
- Fibrinogen fibers cause the platelets to become sticky
- Platelets release chemicals that attract more platelets
- Platelet plug forms due to stickiness
Platelet plug formation
- Blood usually clots within 3 to 6 minutes
- The clot remains as endothelium regenerates
- The clot is broken down after tissue repair
- Injured tissues release TS, which interacts with PF3; a phospholipid that coats the surface of platelets
- Combination with other clotting factors and calcium ions, form an activator that leads to the formation of thrombin which joins soluble fibrinogen proteins into long, hairlike molecules of insoluble fibrinogen which forms a meshwork that traps RBCs and forms the basis of the clot
- Within the hour, clot begins to retract, squeezing serum from mass and pulling ruptures edges of blood vessel together
Coagulation
Disorders of Hemostasis (Undesirable Clotting):
- A clot in a n unbroken blood vessel (blocking passage)
- Can be deadly in areas such as the lungs
Thrombus
Disorders of Hemostasis (Undesirable Clotting):
- Thrombus that breaks away and floats freely in the body
- Can later clog vessels in critical areas such as the brain
Embolus
Disorders of Hemostasis (Bleeding Disorders):
- Insufficient number of circulating platelets
- Arises from any condition that suppresses the bone marrow
- Even normal movement can cause bleeding from small blood vessels that required platelets for clotting
- Evidenced by petechiae
Thrombocytopenia
- Hereditary bleeding disorder
- Normal clotting factors are missing
- Minor tissue damage can cause life-threatening prolonged bleeding
Hemophilia
Blood contains genetically determined proteins known as?
Antigens
Are the “recognizers” that bind foreign antigens
Antibodies
Are substance that the body recognizes as foreign and that the immune system may attack
Antigens
Blood is typed by using ________ that will cause blood with certain proteins to cump and lysed
antibodies
Loses of blood: 15 to 30%
Causes weakness
Loses of blood: Over 30%
Causes shock
Blood types are based on the presence or absence of 2 antigens:
- Type A
- Type B
Presence of both antigens
Blood type AB
Presence of antigen A
Blood type A
Presence of antigen B
Blood type B
Absence of both
Blood type O
What blood type is the universal donor?
O
- Originally identified in Rhesus monkeys
- Named for the eight Rh antigens
Rh blood group
Blood samples are mixed with Anti-A and Anti-B serums, ________ or ________ leads to the identification of blood type
Agglutination; lack of agglutination
Testing for agglutination of donor RBCs by recipients serum
Cross-matching
Expect agglutination will occur for both anti-A and anti-B serum
Blood type AB
Expect agglutination upon addition of anti-B serum
Blood type B
Expect agglutination upon addition of anti-A serum
Blood type A
Expect no coagulation to be observed as there are no surface antigens present
Blood type O
Addition of anti-B serum causes coagulation
Rh+
Are early sites of blood cells formation
Fetal liver and spleen
Takes over hematopoiesis by seventh month
Bone marrow
Form a closed vascular system that transports blood to the tissue and back to the heart
Blood vessel
Vessels that carry blood away from the heart
Arteries and arterioles
Vessels that play a role in exchanges/connection between tissue and blood
Capillary beds
Vessels that return blood back to the heart
Venules and veins
What are the layers in blood vessels?
- Tunica intima
- Tunica media
- Tunica externa
Forms a friction-reducing lining known as the endothelium
Tunica intima
Smooth muscle and elastic tissue, controlled by sympathetic NS
Tunica media
- Forms protective outermost covering
- Mostly fibrous connective tissue
- upports and protects the vessel
Tunica externa
Capillaries are only composed of what layer?
Tunica intima
Thickest layer of the blood vessel
Tunica media
Tunica media: Smooth muscle allows ________ to ensure continuous blood flow
Micro contraction
Tunica media: Elastic tissue allow ________ and extend depending on the blood contraction
Blood vessels to expand
Capillaries only contain 1 layer to allow?
Allow exchange of materials between vessels and organs
How many layers does arteries and veins contain?
3 layers
- Have a heavier, stronger, stretcher tunica media than veins to withstand changes in pressure
- Able to accommodate the pressure change
Arteries
- Thinner tunica media than arteries and operate under low pressure
- Have valves to prevent backflow of blood
- Lumen of veins is larger than of arteries
Veins
________ “milks” blood in veins toward heart; aids to open valve because smooth muscle cannot
Skeletal muscle
- Only one cell layer thick; allows diffusion
- Allow for exchanges between blood and tissue
Capillaries
Blood flow through a capillary bed
Microcirculation
Capillaries form networks called?
Capillary beds
Capillary beds consists of?
- A vascular shunt
- True capillaries
- Branch off a terminal arteriole
- Empty directly into a postcapillary venule
- Entrances to capillary beds are guarded by precapillary sphincters
True capillaries
Ensures no backflow and proper transportation
Precapillary sphincters
Internal carotid arteries divide into
- Anterior cerebral arteries
- Middle/posterior cerebral arteries
Internal carotid arteries supply most of the?
Cerebrum
Join once within the skull to form basilar artery
Vertebral arteries
Serves the brainstem and cerebellum
Vertebral arteries
United by small communicating arterial branches
Anterior and posterior blood supplies
Anterior and posterior blood supplies are united by small communicating arterial branches, resulting to a complete circle of connecting blood vessels called?
Cerebral arterial circle or Circle of Willis
Formed by veins draining the digestive organs, which empty into the hepatic portal vein
Hepatic portal circulation
Carries blood to the liver, where it is processed before returning to systemic circulation
Hepatic portal vein
