Study Guide - Lecture Test 5 Flashcards
Role of normal microbiotic flora in the body
Help establish the immune system
Train immune system to respond only to pathogens
Prevent growth of pathogens
Produce folic acid, niacin, and vitamin K
Destroy some ingested toxins
May cause disease under some circumstances
Characteristics of bacteria
Does not have a nucleus
Usually one circular, double-stranded DNA molecule
Characteristics of viruses
Not alive
Possess either RNA or DNA
Do not reproduce by binary fission, mitosis or miosis
Innate body defenses
First line
-Skin
-Mucous membrane
-Secretions
Second line
-Phagocytic cells
-Natural killer cells
-Antimicrobial proteins
-Inflammatory response
-Fever
Adaptive body defenses
Third line
-Antigens
-antibodies
Lymph node function
Filter and clean lymph before it is returned to blood
Pulmonary circulation function and pump
Function - sends blood to lungs to pick up O2 and remove CO2
Pump - pulmonary pump
Systemic circulation function and pump
Function - Supplies oxygen and nutrient-rich blood to all body organs
Pump - systemic pump
Layers of the heart and the function of each
Epicardium - thin outer layer that covers the outer surface of the heart
Myocardium - thick middle layer that consists of cardiac muscle
Endocardium - thin inner layer the covers surfaces of the heart chamber and valves
Coronary arteries/cardiac veins
Coronary arteries - supply the heart muscle with oxygenated blood
Cardiac veins - drain the myocardium of blood
When do AV valves open and close?
Open - atrial pressure is greater than ventricular pressure
Close - ventricular pressuer is greater than atrial
When do semilunar valves open and close
Open - ventricular pressure is greater than blood pressure in pulmonary trunk or aorta
Close - blood pressure in pulmonary trunk or aorta is greater than ventricular pressure
Artery pathway to lower arm
Left ventricle - ascending aorta - aortic arch - brachiocephalic trunk - subclavian artery - axillary artery - brachial artery - radial/ulnar arteries
Pathway to femoral artery
Left ventricle - ascending aorta - aortic arch - descending aorta - external iliac artery - femoral artery
Branches off aorta
Ascending aorta
-right and left coronary arteries
Aortic arch
-Brachiocephalic trunk
-Left common carotid artery
-Left subclavian artery
Pathways of aorta arch
Left ventricle - ascending aorta - aortic arch - brachiocephalic trunk - right common carotid artery/right subclavian artery
Do arteries carry blood towards the heart or away?
Away from the heart
Are arteries high or low in O2?
High
Layers of blood vesses
Tunica intima
-endothelium
-forms a friction-reducing lining
Tunica media
-smooth muscle and elastic tissue
-controlled by sympathetic nervous system
Tunica externa
-forms protective outermost covering
-mostly fiberous connective tissue
Structural differences between arteries and veins
Arteries have a thicker tunica media to withstand high pressures. Veins have a thinner tunica media and operate under low pressure.
Vein pathway from femoral vein
Femoral vein - external iliac veins - common iliac vein - IVC - right atrium
Vein pathway from lower arm
Radial/ulnar veins - brachial vein - axillary vein - subclavian vein - SVC - right atrium
Do veins carry blood towards the heart or away?
Towards the heart
Are veins high or low in O2?
Low
Do veins have valves?
Yes
Does arteries have valves?
Only the pulmonary trunk and aorta
Pathway of blood through the heart
IVC/SVC-RA-tricuspid valve-RV-pulmonary valve-pulmonary trunk-pulmonary arteries-pulmonary capillaries-pulmonary veins-LA-bicuspid valve-LV-aortic valve-ascending aorta
Where are plasma proteins formed?
In the liver
What is the function of albumin?
Regulates osmotic pressure
Where are erythrocytes formed?
Red bone marrow. Rate of RBC is controlled by the the hormone EPO. Kidneys secrete EPO in response to reduced O2 levels in the blood.
What is hematocrit?
the percentage of whole blood consisiting of erythrocytes - appox 45% of blood
What stem cell produces erythrocytes?
Hemocytoblast - myeloid stem cells
How are old erythrocytes removed?
By phagocytes in the spleen or liver
What is hematopoiesis?
Process of blood cell formation. All blood cells are derived from hemocytoblast
What is the pH of blood?
7.35 - 7.45
What is the temperatue of blood?
100.4 F
What is the most abundant formed element?
Erythrocytes
Classification of white blood cells
Granulocytes - neutrophils, eosinophils, and basophils
Agranulocytes - lymphocytes and monocytes
White blood cells from most to least abundant
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
Count of white blood cells
4800 to 10800 WBCs per mm cubed of blood
Functions of white blood cells
Neutrophils - phagocytes at active sites of acute infection.
Lymphocytes - part of the immune response, fights tumors and viruses
Monocytes - active phagocytes, increase in numbers during chronic infection
Eosinophils - kill parasitic worms, play role in alergy attacks
Basophils - release histamine at site of inflammation
Stem cell of WBCs
Lymphoid stem cell
Blood types by antigen or antibodies
Type A - A antigen, B antibodies, Receive A,O
Type B- B antigen, A antibodies, Receive B,O
Type AB - AB antigen, No antibodies - Universal recepient
Type O - No antigen, AB antibodies, Receive O -Universal donor
What are the three steps of hemostasis?
1.Vascular spasms
2.Platelet plug formation
3.Coagulation (blood clotting)
What is the ductus arteriosus and what does it become after birth?
Blood vessel in the developing fetus connecting the trunk of the pulmonary artery to the descending aorta. Becomes ligamentum arteriosum at birth.
What is the foramen ovale and what does it become after birth?
Allows blood to enter the left atrium from the right atrium. Becomes fossa ovalis at or after birth.
What is the pimary pacemaker of the heart and where is it located?
Sinoatrial node. Located in the right atrium near the SVC
What is the difference between P wave, QRS wave and T wave?
P wave - atrial depolarization
QRS wave - ventricular depolarization
T wave - ventricular repolarization
What is the difference between systolic and diastolic pressure?
Systolic - pressure at the peak of ventricular conraction
Diastolic - pressure when ventricles relax
What are the two heart sounds?
First heart sound - “lub” - closing of the AV valves
Second heart sound - “dub” - closing of semilunar valves
Actions of sympathetic and parasympathetic nervous system on the heart
Sympathetic - increases heart rate
Parasympathetic - decreased heart rate
What are the blood vessels in the umbilical cord?
One umbilical vein - carries blood and oxygen from placenta to the fetus
Two umbilical arteries - carries blood high in CO2 and wate products from the fetus to placenta
What are the receiving and discharging chambers?
Receiving - left and right atria
Discharging - left and right ventricles
What is an antigen?
Any substance capable of stimulating an immune response
What cell produces antibodies?
Plasma cells
What are the classes and functions of antibodies?
IgM - can fix complement
IgA - protects mucosal surfaces
IgD - important in activation of B cell
IgG - can cross the placental varrier and fix complement (most abundant)
IgE - involved in allergies
Function of slime layer of bacteria
Protects bacteria from environmental threats including antibodies and desiccation
What is the function of Interferon?
Prevents virus replication in health cells
What is inflammation and why is it beneficial?
Inflammation is aresponse that is triggered when the body tissues are injured. It’s a defense mechanism against injury and infection.
Process and functions of inflammatory response
Neutrophils squeeze through the capillary walls by diapedesis.
Helps leukocytes reach area of infection
Antibody functions
Neutralization - antibodies bind to specific sites on bacterial exotoxins or virsues to prevent their harmful effects
Agglutination - antibody-antigen binding causes clumping of cells
What is the function of Cytotoxic T cells?
Insert perforin molecules (granzymes) into membrane of abnormal or foreign cell
What is the function of APCs
Help activate lymphocytes, but do not respond to specific antigens.
Engulf antigens and then present antigen fragments on their membrane surface
What cells act as APCs?
Dendritic cells - macrophages and B lymphocytes
What is the function of Helper T cells?
Recruit other cells to fight invaders
Release cytokines
Attract other leukocytes into the area
What is T cell activation?
APC presents antigen to T cell
T cell is activated
Activated T cell undergoes clonal selection
A large number of T cells clones are producted
-Most T cells differentiate into effector T cells
-A few T cells become memory cells
Difference between B cells and T cells
B cells - provide humoral immunity (antibody-mediated immunity)
T cells - provide cellular immunity (cell-mediated immunity)
Difference between active and passive immunity
Active - occurs when B cells encounter antigens and produce antibodies
Passive - occurs when antibodies are obtained from someone else
What is a pathogen?
Microorganism that causes disease
Features of gram-negative bacteria
Appear red or pink with gram stain
Resistant to antibiotics
Most pathogenic bacteria belong to this group
Features of gram-positive bacteria
Appear dark blue or purple with gram stain
Sensitive to antibiotics
Few pathogenic bacteria belong to this group
What is the function of capillaries?
Exchange vessels. Substances are exchanged between blood and surrounding cells/tissues
Where does the right lymphatic duct collect lymph from?
Right upper extremities, right side of head, and thorax
What does the thoracic duct collect lymph from?
Rest of the body
