LAB6 Flashcards
what is the function of blood?
- transports various substances
- regulates several life processes by maintaining homeostasis of bodily fluids
- protection against disease, injury, and infection
what is blood?
a liquid connective tissue that consists of cells surrounded by a liquid extracellular matrix (blood plasma)
how does blood carry out transportation?
- transports O2 from the lungs to the cells of the body and CO2 from the body cells to the lungs
- It carries nutrients and hormones
- transports heat and waste products to various organs for elimination from the body
how does blood carry out regulation?
- circulating blood throughout body
- helps regulate pH by buffers
- adjusts body temp through varying rate of flow through skin where excess heat can be lost from blood
- blood osmotic pressure influences water content of cells
how does blood carry out protection?
- WBCs can phagocytize microbes
- antibodies
- blood can clot, protecting against excessive loss from body after injury
where does hemopoiesis occur in embryo?
yolk sac
where does hemopoiesis occur in the fetus?
lymph nodes, thymus, spleen, liver
where does hemopoiesis occur after birth?
in red bone marrow
what are the three types of formed elements?
- erythrocytes
- leukocytes
- thrombocytes
what are erythrocytes?
small, biconcave, anucleate cells
- contain hemoglobin
what is hemoglobin?
protein with 4 iron atoms, which reversibly bind to oxygen or carbon dioxide molecules
what are thrombocytes?
fragments of megakaryocytes enclosed in a plasma membrane
- form platelet plug to stop blood loss from ruptured blood vessels
- secrete chemicals from their granules that promote blood clotting
what are leukocytes?
have a nucleus and can travel to all parts of the body in the blood and lymph
- can move out of blood vessels by emigration
what are the types of leukocytes?
- eosinophils
- basophils
- neutrophils
- lymphocytes
- monocytes
what is the function of erythrocytes?
Hemoglobin within RBCs transports most oxygen and part of carbon dioxide in blood
what is the characteristics of erythrocytes?
- 7–8 μm diameter
- biconcave discs
- without nuclei
- live for about 120 days
what are some characteristics of neutrophils?
- 10–12 μm diameter, larger than RBC
- nucleus has 2–7 lobes connected by thin strands of chromatin
- cytoplasm has very fine, pale lilac granules, barely stained granules
- 60-70% of WBCs
what are some functions of neutrophils?
- Phagocytosis
- Destruction of bacteria with lysozyme, defensins, and strong oxidants, such as superoxide anion, hydrogen peroxide, and hypochlorite anion
what are some characteristics of eosinophils?
- 10–12 μm diameter
- nucleus often bilobed connected by thick strand of chromatin
- large, red-orange granules fill cytoplasm
- 2-4% of WBCs
what are the functions of eosinophils?
- combat effects of histamine in allergic reactions
- phagocytize antigen–antibody complexes
- destroy certain parasitic worms
what are some characteristics of basophils?
- 8–10 μm diameter
- nucleus has 2 lobes, cannot be distinguished from granules
- large cytoplasmic granules appear deep blue-purple
- 0.5 - 1% of WBCs
what are some functions of basophils?
- Liberate heparin, histamine, and serotonin in allergic reactions that intensify overall inflammatory response
what are some characteristics of lymphocytes?
- small lymphocytes are 6–9 μm
- large lymphocytes are 10–14 μm - nucleus is round or slightly indented
- cytoplasm forms rim around nucleus that looks sky blue
- 20-25% of WBCs
what are the functions of lymphocytes?
- Mediate immune responses, including antigen–antibody reactions
- B cells develop into plasmocytes, which secrete antibodies
- T cells attack invading viruses, cancer cells, and transplanted tissue cells
- Natural killer cells attack microbes and certain spontaneously arising tumor cells
what are some characteristics of monocytes?
- 12–20 μm diameter
- nucleus is kidney- or horseshoe-shaped
- cytoplasm is blue-gray and appears foamy
- 3-8% of WBCs
what are some functions of monocytes?
phagocytosis (after transforming into fixed or wandering macrophages)
what are some characteristics of platelets?
- 2–4 μm diameter cell fragments that live for 5–9 days
- contain many vesicles but no nucleus
why can we not use real blood in labs?
would require gloves, sterile materials, and appropriate sterile and infection control protocols
what is the hematocrit?
measure of % of RBCs in a blood sample
describe how to read a hematocrit card
- bottom of RBCs placed at 0 mark
- slide tube until meniscus of plasma at 100 mark
- line at top of RBCs is hematocrit/packed RBC volume %
what is a hematocrit used for?
- part of complete blood count (CBC)
- can be used in combo with other tests for diagnosing anemia, and polycythemia
- to evaluate dehydration and recovery
- evaluate effectiveness of blood transfusions
what is a buffy coat?
layer of WBCs and platelets above the RBC layer on a centrifuged blood sample
- on top of RBCs b/c RBCs have Fe2+, very heavy ion and WBCs and platelets do not have it
what are some conditions that can result in an increased hematocrit?
- dehydration
- blood doping
- living at high altitudes long term
- excessive red blood cell production
what are some conditions that can result in a decreased hematocrit?
- anemia
- pregnancy
- Vitamin/mineral deficiency
- leukemia
- hemorrhage
- liver cirrhosis
- hormone deficiences
what are agglutinogens?
genetically determined antigens on the surface of RBCs that are recognized by own immune system but not by others
what are some examples of foreign antigens?
- pollen
- dust
- cells w/ membranes that contain foreign surface markers
what are agglutinins?
antibodies that begin to appear in plasma within a few months after birth and react to specific foreign antigens to inhibit or destroy them
what is the source of antibodies in the antibody-mediated immune response?
lymphocytes, specifically B cells
what blood type is the universal donor?
O-
what blood type is the universal recipient?
AB+
how does agglutination differ from clotting?
- agglutination is due to antibodies, an immune-system mediated response to foreign blood cells
- blood clotting is due to thrombocytes, occurs when there is blood or vessel trauma, not necessarily foreign
what is agglutination?
clumping of blood cells when antibodies in the plasma of the receiving blood will cross-link with the foreign antigens on the donated RBCs
what are antiserums?
solutions that contain an antibody, used to determine blood type by detecting presence or absence of an antigen
How is Rh blood group different from ABO blood group?
- only one antigen resulting in two different blood types
- a person does not get antibodies after birth, only gets antibodies after an initial exposure
what is RhoGAM?
an injection that can prevent maternal sensitization and hemolytic disease of the newborn
- immunoglobin binds to fetal RBCs with antigen before mom’s immune system can produce a response
- given at week 28 and within 72 hours of delivery
what is Hemolytic Disease of the Newborn (HDN) / Erythroblastosis fetalis?
Rh- mother and Rh+ fetus
- after an initial exposure, mother’s Rh antibodies cross placenta and cause Rh+ fetus’s RBCs to agglutinate and hemolyze, resulting in HDN
what is a finger pulse oximeter?
a device that measures blood oxygen saturation and pulse rate
- determines arterial oxygen saturation of functional hemoglobin as a %age
what is hypoxemia?
a reading of less than 90% on the finger pulse oximeter
what is a normal oxygen saturation value?
97-99%
what is the difference between hypoxemia and hypoxia?
hypoxemia is a reading of <90%
hypoxia is insufficient oxygen
where is the heart located in the body?
in the mediastinum within the thoracic cavity
what is the pericardial membrane?
membrane that surrounds and protects the heart
what does the pericardium consists of?
- a tough outer layer of fibrous pericardium that attaches to diaphragm and large blood vessels, anchoring heart to mediastinum
- an inner delicate layer of serous pericardium
what are the two layers of the serous pericardium?
- parietal pericardium (epicardium) that is fused to fibrous pericardium
- visceral pericardium that forms outer layer of heart
what is the pericardial cavity?
cavity between the parietal and visceral pericardium that is filled with serous fluid
what is the myocardium?
- middle layer of the heart composed of cardiac muscle tissue
what is the function of the myocardium?
the contraction of the myocardium supplies the force to circulate blood throughout the body
what is the endocardium?
thin layer of connective tissue underlying endothelium that lines the inner surface of the heart and its valves
What is the source of serous fluid? What is its function?
- secreted by serous pericardium
- reduces friction between the layers of the serous pericardium as the heart moves
How does the function of the four heart valves differ?
SL:
- allow ejection of blood from the heart into arteries but prevent backflow of blood into the ventricles
AV:
- allows blood to flow in one direction only, from an atrium into a ventricle
- blood cannot regurgitate into atria when ventricles contract as chordae tendinae prevent valve cusps from everting in response to high ventricular pressure
How does the structure of the four heart valves differ?
SL:
- made up of three crescent moon–shaped cusps
- located btwn vessels and ventricles
AV:
- located btwn atrium/pulmonary trunk and a ventricle
- have leaflets
- chordae tendinae and papillary muscles
what keeps the AV valves from everting when the ventricles contract?
- chordae tendinae
- papillary muscles
what is the structure and function of the intercalated discs?
- link cells together and define borders
- cardiac cell-cell communication
- coordinate muscle contraction and maintenance of circulation
- has gap junctions and desmosomes
what is an atrioventricular valve?
A heart valve made up of membranous flaps or cusps that allows blood to flow in one direction only, from an atrium into a ventricle
What is a semilunar valve?
A valve between the aorta or the pulmonary trunk and a ventricle of the heart.
what is the ligamentum arteriosum?
connects the aortic arch and pulmonary trunk
- remnant of ductus arteriosus
what are trabeculae carneae?
Ridges and folds of the myocardium in the ventricles
- prevents backflow of blood into atria by preventing inversion of bicuspid and tricuspid valves
what are chordae tendinae?
Tendonlike, fibrous cords that connect atrioventricular valves of the heart with papillary muscles
- - prevents backflow of blood into atria by preventing inversion of bicuspid and tricuspid valves
what are papillary muscles?
cone-shaped trabeculae carneae that connect to chordae tendinae
- - prevents backflow of blood into atria by preventing inversion of bicuspid and tricuspid valves
what is the interventricular septum?
a partition that separates the right from the left ventricle
what is the pulmonary semilunar valve?
valve where blood from right ventricle passes through into the pulmonary trunk
what is the pulmonary trunk?
blood vessel that divides into left and right pulmonary arteries and carry blood into lungs
what is the right ventricle?
ventricle that forms most of anterior surface of heart
what is the left ventricle?
thickest chamber of the heart that forms the apex of the heart
what is the right atrium?
heart chamber that forms the right surface of the heart and receives blood from superior and inferior vena cava and coronary sinus
what is the left atrium?
heart chamber that forms most of the base of the heart, receives blood from the lungs through pulmonary veins
what is the interatrial septum?
a partition inside the heart that separates the right and the left atrium
what is the fossa ovalis?
an oval depression on the interatrial septum
- remnant of the foramen ovale in the fetal heart
- prevents blood exchange btwn right and left atria
what is the right atrioventricular valve?
valve in the heart where blood from right atrium passes into right ventricle
- consists of three cusps
what is the left atrioventricular valve?
valve in the heart where blood from left atrium passes into the left ventricle
- bicuspid, two cusps
what is the aortic semi-lunar valve?
valve in heart where blood passes from left ventricle into the ascending aorta
what are coronary arteries?
arteries that branch from ascending aorta and carry blood to the heart wall
what is the coronary sulcus?
a depression that encircles most of the heart and marks the external boundary between the superior atria and inferior ventricles
what is the anterior interventricular sulcus?
a shallow groove on the anterior surface of the heart that marks the external boundary between the right and left ventricles on the anterior aspect of the heart
what is the posterior interventricular sulcus?
a depression on the posterior surface of the heart which marks the external boundary between the ventricles on the posterior aspect of the heart
what is the right atrium’s auricle?
wrinkled pouchlike structure that increases capacity of the right atrium
what is the left atrium’s auricle?
wrinkled pouchlike structure that increases capacity of the left atrium
what is the superior vena cava?
vein carrying deoxygenated blood from superior portion of body towards the heart
what is the inferior vena cava?
vein carrying deoxygenated blood from inferior portion of body towards the heart
what is the opening of the coronary sinus?
opening in right atrium where deoxygenated blood from coronary sinus passes through and empties into right atrium
what are cardiac veins?
veins that are part of the coronary circuit, encircles the heart
- collects deoxygenated blood and wastes from myocardium and empties it into right atrium via coronary sinus
what are coronary arteries?
arteries which brance from ascending aorta and encircle the heart
- supplies oxygenated blood and nutrients to the myocardium
what is the aortic arch?
part of aorta between ascending and descending aorta
- gives rise to three branches of arteries
- brachiocephalic trunk
- left common carotid artery
- left subclavian artery
what is the ascending aorta?
first part of aorta
- pumps blood through aortic arch and into descending aorta
why does O2 saturation levels stay consistent during exercise?
- you increase amt of O2 you need during exercise
- you also increase amt of O2 you intake by breathing more
what is sickle cell anemia?
disease that leads to sickle-shaped RBCs
- substitution of amino acid in hemoglobin deforms RBC into sickle-shape
what is chronic lymphocytic leukemia?
cancer of lymphatic tissue where WBC:RBC ratio is 50:50
- WBCs do not differentiate fully and do not undergo apoptosis
what is hemolytic disease of the newborn?
erythroblastosis fetalis
- nucleated RBCS and erythroblasts in blood to compensate for RBC destruction
- Rh- mother has Rh+ baby after an initial exposure, mother’s anti-Rh antibodies seek to destroy RBCs of baby
what is African sleeping sickness?
disease where infected Tsetse fly introduces Trypanosoma gambiense into blood, toxic metabolites of the parasite produce necrotic damage to cells they come into contact with, including RBCs
