Midterm #2 (Units 4,5,6) Flashcards
(213 cards)
1
Q
What is the series of tubes (blood vessels) connected to a pump (the heart)?
A
Vascular system
2
Q
T or F: Blood is constantly moved through the system to all regions of the body, supplying blood cells with nutrients and gases
A
True
3
Q
T or F: The vascular system not only delivers oxygenated blood to the organs but it also plays an important role in removing waste from our organs as well
A
True
4
Q
What are the three parts of the circulatory system?
A
- A pump
- Carrying Vessels
- Small Vessel Networks and Capillary beds
5
Q
T or F: Some exchanges happen in the capillary beds
A
False: ALL exchange happens in the capillary beds
6
Q
What is the pump of the circulatory system?
A
The heart
7
Q
What are the carrying vessels of the circulatory system?
A
- Arteries
- Arterioles
- Venules
- Veins
8
Q
What does the term ‘atrium’ refer to?
A
refers to the cavity of the auricle
9
Q
The fusion of 2 muscular pumps, the left and right side, each with an upper chamber (auricle) and lower chamber (ventricle): what am I?
A
The heart
10
Q
The ____ have relatively thin walls compared with the ventricle walls.
A
Atria
11
Q
T or F: The right ventricle is much thicker than that of the left ventricle
A
FALSE: The wall of the LEFT ventricle is much thicker than that of the right ventricle
12
Q
T or F: Contraction of the ventricular muscle forces blood into the major arteries that lead away from the heart
A
true
13
Q
Blood moves from major ____ leading into the atria.
A
veins
14
Q
Contraction of the atrial muscles forces the blood through to the ______
A
ventricle
15
Q
Define: Diastole
A
the period when cardiac muscles are relaxing to allow for filling of the atria and ventricles
16
Q
Define: Systole
A
The period of atrial or ventricular muscle contraction (higher pressure)
17
Q
What is our resting blood pressure?
A
120/80mmHg (systolic/diastolic)
18
Q
What are the two types of flap-valves in the heart that prevent backflow of blood during contraction (systole) of ventricular muscles?
A
- Atrioventricular valve (AV)
2. Semilunar Valve (SL)
19
Q
What are the two pacemakers in the body?
A
- Sinoatrial node (SAN)
- Atrioventricular node (AVN)
20
Q
Cells of the _______ node spontaneously initiate action potentials that spread over the atria, this stimulates the ________ node to produce action potentials that pass along the Purkinje fibres and stimulate contraction of ventricles.
A
sinoatrial; atrioventricular
21
Q
Direct delivers of the APs to the ventricles by the Purkinje fibres ensures that the chambers contract from the _______ ____
A
bottom up
22
Q
Why do we need two pacemakers?
A
BC we need contraction to start at the bottom of the ventricle up
23
Q
T or F: The heart does not need nerves to stimulate an action potential, its spontaneous
A
true
24
Q
The rates of SAN excitation are governed by the _______ nervous system
A
autonomic
25
_______ from parasympathetic neurons slows the heart rate
Acetycholine
26
_______ from the sympathetic neurons speeds up the heart rate
Epinephrine
27
What is an ECG (electric cardio gram)
- waves of electric current measured on the surface of the skin
- surface recording- measure of all the electrical changes happening in the heart during one cardio cycle "Lub-Dub"
28
What is a "P wave"?
- the very first electrical change in heart
- initiated by the pacemaker
- depolarizes atria
29
What is the job of the "T wave"?
Ventricle relaxation/ ventricular repolarization
30
______ repolarization happens somewhere between Q and S- it is masked by the massive ventricular depolarization
Atrial
31
What is the main purpose of the heart?
Maintaining homeostasis- cares about blood pressure (how much volume you put into the system)
32
T or F: Blood pressure differs between species
False: Blood pressure remains the same throughout all species
33
What are the resting heart rates for rats, humans and elephants?
Rats: 500 beats/min
Humans: 60 beats/min
Elephants: 15 beats/min
34
Define: Cardiac Output
the amount of blood ejected by the heart over one minute.
- amount of blood expelled from the heart varies depending on the physiological need
- can be affected both by heart rate and by the volume of blood moved with each contraction
35
Define: Stroke Volume
- The volume of blood pumped by each ventricle in one contraction/ one heartbeat
- autoregulated
36
What are the short forms for heart rate and stroke volume?
HR= Heart Rate = beats/min
SV= Stroke Volume = L/contract (or beat) = L/min
CO (cardiac output) = HR x SV
37
What is Starling's Law?
- the more cardiac muscle is stretched, the stronger the contraction
38
Discuss Heart Output
- systolic volume is largely regulated by the amount of blood returning to the heart via the major veins
- all of the blood returning to a healthy heart is pumped out in each cycle
- changing heart rate is the most common way to change cardiac output
39
What is happening in the body when there is congestive heart failure?
- ventricular muscle is weakened (poor blood supply)
- blood pools and the heart enlarges
- ventricular muscle is stretched and becomes weaker and the subject may eventually die
40
What are the three processes of the vascular system?
1. carries blood away from the heart (arteries, arterioles)
2. Exchanges occur between tissues and blood (capillary beds)
3. Return blood toward the heart (venules, veins)
41
______ have a thick smooth muscle wall encased in a thick connective tissue sheath
arteries
42
As blood moves away from the heart it passes through successively smaller artery-like vessels, called __________.
arterioles
43
True or false: Arteries contain valves
False: arteries contain NO valves
44
True or False: Arteries carry oxygenated blood towards the heart.
False: Arteries carry oxygenated blood AWAY from the heart
45
_____ receive the blood that drains from the capillary beds
venules
46
_____ have thinner walls and less smooth muscle than arteries
veins
47
_____ carry deoxygenated blood towards the heart
Veins
48
What is the purpose of vascular valves?
- ensures blood moves towards the heart (prevents back flow)
| - Contraction of skeletal muscle pressing on veins causes the displacement of the blood
49
What are the differences between blood vessels?
- arteries have thicker smooth muscle layer than veins
- capillaries are only one cell layer to allow for exchanges between blood and tissue
- veins have a thinner smooth muscle layer than arteries
50
What are capillary beds/exchange vessels?
- networks of thin-walled vessels in body tissues responsible for transfer of nutrients and waste products
51
What are the advantages of the small size of capillary beds?
- increased surface area
| - makes for ideal diffusion conditions (moving from high to low concentrations)
52
What is a vascular shunt?
- directly connects venule without going through the capillary bed (bypass)
53
What is a true capillary?
-exchange vessel (oxygen, nutrients, carbon dioxide)
54
The flow through capillary beds is regulated by series of smooth muscle bands called _______ _______.
precapillary sphincters (PS)
55
What do precapillary sphincters do?
- encircle the root of each capillary; when they contract blood flow through that capillary is reduced or stopped
56
What are the two functions of the vascular shunt?
1. normal exchange- blood passes through the capillary bed (Relaxed)
2. Contracted- blood bypasses the capillary bed capillary vessels
57
The _______ circuit pumps blood from the right side of the heart to the lungs then returns blood to the left side of the heart.
pulmonary
58
The _______ circuit pumps blood from the left side of the heart to all parts of the body then returns blood to the right side of the heart.
systemic
59
What are the advantages of the double pulmonary/systemic circuit?
- two in-line pumps are needed in order to maintain sufficient and optimal blood pressure to push blood through the networks of the capillary beds
- the small diameter of the capillary beds imposes a high resistance to blood flow and this leads to a steep fall in blood pressure as blood flows through multiple capillary beds
60
______ carry oxygenated blood.
Arteries
61
_______ carry deoxygenated blood.
Veins
62
What is blood pressure?
- the force that moves blood through the closed circulatory system
63
What is vasoconstriction?
"closing" of vessels (increase in blood pressure)
| - temperature induced response
64
What is vasodilation?
"opening" of vessels (decrease in blood pressure)
| - regulated by the sympathetic division of ANS
65
What are the 4 ways small substances pass into and out of capillaries?
1. Through the capillary cells (direct diffusion)
2. Through clefts between capillary cells
3. Through fenestrations (windows/pores) in the wall of the capillary (for larger and insoluble substances)
4. Transferred in vesicles, by exocytosis and endocytosis
66
What two forces work against each other in the capillary exchange of fluids?
Hydrostatic pressure (BP) and osmotic pressure (proteins attract water from outside the capillary beds) work against each other.
67
Which system keeps water in homeostatic ranges?
Lymphatic system
68
Define: Edema
Fluid accumulation
69
List four biologically important substances that blood transports:
1. Nutrients
2. Nitrogenous waste products of metabolism
3. Respiratory gases
4. Many hormones
70
List three types of formed elements:
1. Erythrocytes
2. Leukocytes
3. Platelets
71
What are erythrocytes?
- Red blood cells
- regulated by kidney
- most abundant group of cells
- for transport and delivery of respiratory gases
- regulated by metabolic rate of the individual
72
What are leukocytes?
- White blood cells
- regulated by colony stimulating factor and interleukins
- fundamental defence system
- located in lymphatic system, lymph nodes
73
What are platelets?
cell fragments
| - important factors in the process of clot formation in wound repair
74
What are red blood cells?
- small disc-shaped cells
- major contributor to the viscosity of blood
- contain hemoglobin which gives blood its bright red colour
- do not contain a nucleus
75
What are the two types of leukocytes?
- Granulocytes
| - Agranulocytes
76
What are the three types of granulocytes?
- Neutrophils
- Eosinophils
- Basophils
77
What do basophils do?
produce and release histamine as part of the inflammatory response
78
What do eosinophils do?
attack parasitic worms, fight infections
79
What are the two types of Agranulocytes?
- Lymphocytes
| - Monocytes
80
What is hematopoiesis?
- blood cell formation
- come from common blood stem cell
- formed and reside in bone marrow
81
True or false: Erythrocytes wear out in 100 to 120 days
True
82
Define Hemostasis:
Stoppage of bleeding resulting from a break in a blood vessel
83
What are the three phases of homeostasis?
1. Vascular Spasms
2. Platelet Plug Formation (temporary blockage of blood flow in the injured area)
3. Coagulation (blood clotting)
84
Role of platelets in hemostasis:
Undamaged blood vessel: platelets do not interact with the lining of the blood vessel
Damaged blood vessel: platelets respond instantly to exposed connective tissue and release chemicals onto their surface that makes them stick to the inner wall of the blood vessel
85
Why do we need body defences?
- the body is constantly in contact with bacteria, fungi, and viruses
86
What are the two defence systems for foreign materials?
- Innate (non-specific)
| - Adaptive (specific)
87
What does the innate defence system target?
- ALL pathogens
88
What does the Adaptive defence system target?
- Specific pathogens
| - fight it at earlier stages of invasion
89
What are the 3 lines of defence?
1st line- physical barriers
2nd line- results in general body response
3rd line- selective attack
90
Unbroken skin is an _______ barrier to invasion by surface microorganisms
effective
91
Mucus producing cells that line the lungs, the large bowel and the female reproductive tract provide protection from invasion by:
microorganisms
92
Macrophage cells "patrol" the lungs, intestinal tract and _______ tract and attack foreign agents before they become a problem
reproductive
93
List some body defences that destroy infectious agents (2nd and 3rd):
- antibodies (immunoglobulins)
- natural killer cells
- interferon
- inflammation
- fever
- the development of immunity to disease/specific pathogens
94
What are some other body defences?
- Pain
- Reflex responses
- Fear
- Cognition
95
Epidermis of the skin is made up of dead cells that are filled with ______, a tough fibrous protein
keratin
96
The skin as a whole organ system provides protection from which various kinds of damage?
- mechanical damage
- bacterial infection
- chemical damage
- loss of tissue water
- ultraviolet radiation
- heat damage to internal tissues
97
______ (sweat) glands secrete an acidic solution that slows down bacterial growth
Eccrine
98
_______ (oil) glands associated with hair follicles secrete sebum which contains anti-bacterial compounds that kill bacteria before they invade the skin surface
Sebacceous
99
_______ membranes line all body cavities that are open to the exterior
Mucous
100
What is the goal of Lymph?
To pick up fluid at capillaries and return to circulation
101
______, along with antimicrobial proteins, natural killer cells, and the inflammatory response, are part of the second line defences
phagocytes
102
What happens during phagocytosis?
- phagocyte engulfs particles (phagosome)
- Lysosome fuses with vesicle (phagolysosome)
- enzymes digest pathogen
- debris is exocytosed
103
______ circulate in blood and exit blood vessels at the sites of infection
Neutrophils
104
How do neutrophils know where to go?
- they detect inflammatory chemicals that are released at the site of tissue damage/infection
- respond to these chemicals by developing a sticky membrane that anchors them on the wall of the blood vessel in the proximity of cytokine production
105
Where are natural killer cells found?
found in blood and lymph; they destroy virus-infected cells and some cancerous cells
106
What protein do NKCs release when they attach to the target cell?
Perforin
107
What are interferons?
- antimicrobial proteins
- chemicals produced by cells that haven't been infected by viruses yet
- bind to cells that have been infected by viruses and help provide some level of protection from infection
108
_______ is the sign of disease.
Inflammation
109
The chemical _______ is released from mast cells that are scattered throughout the body and basophils
histamine
110
What happens during an inflammatory response?
- neutrophils migrate to the affected area
- they squeeze through capillary wall (diapedesis)
- neutrophils accumulate at the site of injury and consume foreign material
111
What does histamine cause?
- causes arterioles in the affected area to dilate therefore blood is brought to the area (redness)
- causes the capillaries in the affected area to become leaky and edema occurs on purpose to increase the 'washing out' of the infected area
112
What are fevers caused by?
- caused by pyrogens, chemicals secreted by leukocytes, that act on the hypothalamus and 'reset' the body's thermostat
113
What are the three features of adaptive defence? (3rd line of defence)
1. Antigen Specific- recognizes and acts against particular foreign substances
2. Systemic- not restricted to the initial infection site
3. Memory- recognizes and mounts a stronger attack on previously encountered pathogens
114
Define: antigen
the term antigen is used to describe the foreign substance/pathogen that elicits an immune response
115
Examples of common antigens:
- foreign proteins
- foreign nucleic acids
- large carbohydrates
- some lipids
- pollen grains
- microorganisms
116
List two types of immunity:
1. Humoral Immunity- antibody mediated immunity
| 2. Cellular Immunity- cell mediated immunity
117
B-Type Lymphocytes are involved in:
antibody-mediated immunity
118
T-Type lymphocytes are involved in:
cell-mediated immunity
119
Where do lymphocytes originate?
from hemocytoblasts in the red bone marrow
120
B-Lymphocytes become activated in the ____ _____
bone marrow (remember B for Bone marrow)
121
T-lymphocytes become activated in the _____
thymus (remember T for thymus)
122
What is the structure of an antibody?
- two identical amino acid chains are linked to form a heavy chain
- the other two identical chains are light chains
- light chains = stability
- Heavy chains = binding properties
123
What is the primary response of humoral response?
- initial encounter with antigen
- B cells activated
- plasma cells secrete antibody
124
What is the secondary response of humoral response?
- memory cells are long-lived
- a second exposure causes a rapid response
- the secondary response is stronger and longer lasting
125
How is immunity acquired?
- Immunity can be acquired naturally and artificially and both forms can be acquires actively or passively
126
Active Immunity:
B cells encounter antigens and produce antibodies contracted naturally or administered
127
Passive Immunity:
antibodies are obtained from someone else or from external source (eg. mother's milk)
128
Actively acquired natural immunity:
involved infection by a pathogen and the development of antibodies and cytotoxic T cells
129
Passively acquired natural immunity:
takes the form of antibodies that are passed from the mother to fetus via the placenta, or mother to infant via milk
130
Actively acquired artificial immunity:
involves infection by dead or weakened pathogens and the development of antibodies and cytotoxic T cells (vaccination)
131
The body defence system is divided into:
Non-specific defences: do not target specific pathogens or antigens
Specific Defences: target specific antigens and provide immunity against further invasion by the same antigen
132
First line of defence summary:
- Physiological: Homeostasis
- Anatomical: skull and vertebral column, meninges and fluid buffers to protect the nervous system, ribs to protect the lungs
- Barrier defences: skin and mucus membranes
- Sensory systems and reflexes: pain receptors and withdrawal reflexes
133
Second line of defence summary:
- Phagocytes: macrophages (patrolling specific organs), neutrophils (circulating in blood- leave blood and move to infected sites)
- Natural killer cells: produce perforin to lyse virus-infected cells and cancer cells
- Chemical agents: interferon, pyrogens, histamine
134
Third line of defence summary:
- B cells:
* activated by specific antigens to produce specific antibodies
* memory cells can be activated by the same antigen later
* antibodies on the surface of target cells allow complement fixation and lyse the cells
- T Cells:
* helper T-Lymphocytes are presented with antigens by macrophages and release chemicals that stimulate cytotoxic killer t-lymphocytes (CKTs)
* the activated CKTs lyse target virus-infected cells, cancer cells and foreign cells
* Memory cells can be activated by the same antigen later
135
What is respiration?
A complex exchange of chemicals between multiple systems
136
Living cells use _____ to power their cellular function.
energy (ATP)
137
How is ATP produced?
ATP is produced in mitochondria by oxidizing nutrients and incorporating the released energy into high-energy phosphate bonds of ATP
138
What is the act of oxidizing?
The stealing of electrons from a substance
139
What is the equation of respiration?
O2 + glucose --> H2O + CO2 + energy --> ATP
140
Where is CO2 produced in the cell?
The mitochondria and the cytoplasm
141
Where is H2O produced in the cell?
the mitochondria
142
True or False: Anaerobic respiration uses a respiratory electron transport chain but does NOT use oxygen as the electron acceptors
True
143
The _____ cavity is the route for transfer of air and food.
oral
144
The _____ cavity moistens air and traps incoming foreign particles.
nasal
145
What is the more common name for the Pharynx?
Throat
146
What is the more common name for the Larynx?
Voice Box
147
Trachea and bronchi are kept open by:
cartilage rings
148
What are alveoli?
This walled connective tissue.
149
What level does gas exchange occur on?
Occurs at the level of alveoli
150
Gas crosses the respiratory membrane by:
Diffusion (high to low concentration)
151
What is surfactant?
- a lipid molecule
- coats gas-exposed alveolar surfaces
- produced by epithelia cells
- covers alveoli and alveoli sacs from the inside
152
What are alveolar macrophages?
- (dust cells)
- add protection by picking up bacteria, carbon particles and other debris
- first line of defence
153
What are the two defence mechanisms that protect the lungs against pathogens?
- Movement (by cilia) of mucous away from the alveoli restricts the accumulation of bacteria, viruses and particulate matter
- Pulmonary macrophages patrol the alveolus epithelium and remove bacteria and various debris/pathogens from the alveoli
154
What are the two phases of breathing?
1. Inspiration = Inhalation (flow of air into lungs)
| 2. Expiration = Exhalation (air leaving lungs)
155
What happens during inspiration?
- Diaphragm moves downwards and external intercostal muscles contract (stretching)
156
What is the tidal volume of lungs?
- normal quiet breathing which moves about 500mL of air with each breath
157
What is the residual volume of lungs?
- 1200mL of air
| - No matter how hard you try, you will not be able to completely empty your lungs.
158
Define: Eupnea
normal respiratory rate
159
Define: Hyperpnea
Increased respiratory rate often due to extra oxygen needs
160
Define: Apnea
A period where ventilation stops usually ending in a sharp inspiration
161
Define: Hyperventilation
- results from increased CO2 in the blood
- breathing becomes deeper and more rapid
- Blows off more CO2 to restore normal blood pH
162
Define: Hypoventilation
- results when blood becomes alkaline, diminished CO2 circulation
- extremely slow or shallow breathing
- allows CO2 to accumulate in the blood
163
What are the four events of respiration?
1. Pulmonary Ventilation
2. External Respiration
3. Respiratory Gas Transport
4. Internal Respiration
164
What is pulmonary ventilation?
-moving air in and out of the lungs (breathing)
165
What is External Respiration?
- gas exchange between pulmonary blood and alveoli
- oxygen is loaded into the blood
- carbon dioxide is unloaded from the blood
166
What is Respiratory Gas Transport?
- transport of oxygen and carbon dioxide via the bloodstream
167
Internal Respiration
- gas exchange between blood and tissue in systemic capillaries
168
Gas Exchange Summary:
- External respiration = acidity decreases (CO2 unloaded)
| - Internal Respiration = acidity decreases (O2 unloaded)
169
Adjacent cardiac muscle cells are joined together end-to-end in the cardiac muscle by:
a. intercalated discs
b. sarcomeres
c. purkinje fibres
d. sinoatrial nodes
e. axons
a. intercalated discs
170
which of the following is (are) true of arteries?
a. they are thin walled
b. they are thick walled
c. they carry blood away from the heart
d. they carry blood toward the heart
e. both b and c are correct
E. Both b and c are correct
171
Which of the following blood cells do not contain nuclei?
a. erythrocytes
b. platelets
c. leukocytes
d. plasma cells
e. both a and b are correct
e. both a and b are correct
172
Each is true about erythrocytes except that they:
a. are produced by bone marrow
b. form a cell called the reticulocyte
c. have a high surface-to-volume ratio
d. have plasma membrane proteins that are different among persons
e. lack a nucleus at maturity
B. form a cell called the reticulocyte
173
A normal white cell count reveals 4200 cells of one type per unit of blood. This white cell is the:
a. basophil
b. eosinophil
c. lymphocyte
d. monocyte
e. neutrophil
E. Neutrophil
174
Blood flowing from the lungs to the heart in the pulmonary veins enters:
a. left atrium
b. right atrium
c. aorta
d. left ventricle
e. right ventricle
A. left atrium
175
Which of the following will decrease the resistance to blood flow in a blood vessel?
a. an increase in blood viscosity
b. an increase in vessel diameter
c. an increase in vessel length
d. all of the above
e. none of the above
B. an increase in vessel diameter
176
Cardiac action potentials are transmitted from the pacemaker region throughout the rest of the heart by:
a. gap junctions between adjacent muscle cells
b. nerves from the pacemaker region that synapse on the individual cardiomyocytes
c. paracrine agents released from cardiac muscle cells
d. chemical synapses between adjacent cardiac muscle cells
e. none of the above
b. nerves from the pacemaker region that synapse on the individual cardiomyocytes
177
The region of the heart that normally has the highest rate of spontaneous action potential firing is:
a. AV bundle
b. atrioventricular node
c. sinoatrial node
d. purkinje fibres
e. all of these sites generate action potentials at the same rate
c. sinoatrial node
178
The path of blood flow within the systemic vascular system is:
a. arterioles, arteries, capillary beds, veins, venules
b. arterioles, arteries, venules, veins, capillary beds
c. arteries, arterioles, capillary beds, venules, veins
d. arteries, arterioles, capillary beds, veins, venules
e. arterioles, arteries, capillary beds, venules, veins
c. arteries, arterioles, capillary beds, venules, veins
179
An increase in parasympathetic activity causes:
a. a decrease in both heart rate and cardiac output
b. an increase in heart rate and a decrease in cardiac output
c. an increase in both heart rate and cardiac output
d. a decrease in heart rate and an increase in cardiac output
e. no change in both heart rate and cardiac output
A. a decrease in both heart rate and cardiac output
180
According to Starling's Law:
a. changing heart rate does not affect the cardiac output
b. when venous return decrease, stroke volume increases
c. the heart cannot compensate for changes in blood volume
d. the heart normally pumps out all of the blood returning to it
e. blood volume is kept constant throughout the body
D. the heart normally pumps out all of the blood returning to it
181
The layer of the heart wall synonymous with the visceral layer of the serous pericardium is:
a. epicardium
b. parietal layer of the serous pericardium
c. endocardium
d. myocardium
e. either endocardium or epicardium
A. epicardium
182
The friction blood encounters as it flows through the vessels is a reason for changes in:
a. diastolic pressure
b. stroke volume
c. osmotic pressure
d. cardiac output
e. peripheral resistance
E. peripheral resistance
183
In which of the following blood vessels is blood pressure the highest?
a. arteries
b. arterioles
c. capillaries
d. veins
e. vena cava
A. Arteries
184
Each is a non-specific defense mechanism except:
a. acid secretion in the stomach
b. blood coagulation
c. antigen-antibody reaction
d. epithelial cells secretion of mucus
e. skin protection
c. antigen-antibody reaction
185
Which leukocytes can be transformed into tissue macrophages?
a. basophils
b. lymphocytes
c. monocytes
d. neutrophils
e. none of the above
C. monocytes
186
Chemotaxis is:
a. cell damage resulting from the release of toxins by bacteria
b. destruction of microbes by chemical agents released or activated by lymphocytes
c. migrations of neutrophils from the blood to areas of injury
d. production of antibodies in response to invading antibodies
e. massive release of perforins by virus-infected cells
C. Migrations of neutrophils from the blood to areas of injury
187
The first step in phagocytosis is:
a. contact between phagocyte and microbe
b. endocytosis of phagosome
c. formation of phagosome
d. hydrolysis of foreign molecule
e. exocytosis of proteolytic enzymes
A. contact between phagocyte and microbe
188
Complement consists of a series of proteins, some of which:
a. are activated by antibodies
b. directly destroy microbes by damaging the microbial membrane
c. greatly increase the rate at which microbes are phagocytized by macrophages
d. all of the above
e. none of the above
D. all of the above
189
The large lymph vessels empty into the:
a. left atrium
b. hepatic portal veins
c. aorta
d. large veins in the neck
e. right atrium
D. large veins in the neck
190
T-lymphocytes are:
a. produced in the bone marrow and differentiate in the thymus
b. produced by the liver and spleen and differentiate in the lymph nodes
c. produced by lymph nodes and differentiate in the thymus
d. produced by the thymus and differentiate in the bone marrow
e. produced by the thymus and differentiate in the lymph nodes and spleen
A. produced in the bone marrow and differentiate in the thymus
191
T cells (helpers) may activate B cells by:
a. carrying out phagocytosis
b. enhancing B cell mobility
c. offering memory functions
d. producing specific antibodies
e. releasing cytokines
E. Releasing cytokines
192
Interferon:
a. increases the production of T cells
b. protects healthy, non-affected cells against viral infections
c. destroys antigens in the bloodstream
d. destroys viruses before they enter cells
e. none of the above
B. protects healthy, non-affected cells against viral infections
193
Which of the following is not true of natural killer cells?
a. they are found in blood and lymph
b. they produce antibodies
c. they cause cells to lyse
d. they secrete the protein perforin
e. they destroy virus-infected cells
B. they produce antibodies
194
Histamine is:
a. released from mast cells in response to tissue injury
b. secreted by B-cells
c. synthesized by the spleen
d. an important blood clotting factor
e. none of the above
A. Released from mast cells in response to tissue injury
195
Each is true about antigens except:
a. they are distinguished by lymphocytes
b. they are foreign substances
c. they trigger immune responses
d. lipid molecules are most antigenic
e. proteins are most antigenic
D. lipid molecules are most antigenic
196
During the process of antibody formation, macrophages present a processed bacterial antigen to:
a. helper T cells
b. B cells
c. NK cells
d. both a and b
e. both a and c
D. Both a and b
197
The cell type attacking virus infected cells is the:
a. effector macrophage
b. NK cell
c. T cell
d. All of the above
e. none of the above
d. all of the above
198
Vaccination is an example of:
a. natural active immunity
b. natural passive immunity
c. artificial active immunity
d. artificial passive immunity
e. none of the above
C. artificial active immunity
199
The lungs perform which of the following functions?
a. assist in regulation of body temperature
b. produce erythrocytes and hemoglobin
c. regulate blood acidity
d. synthesize and secrete hormones
e. absorb and store nutrients
C. regulate blood acidity
200
Select the correct sequence of respiratory compartments encountered by exhaled air.
a. bronchiole – nasal cavity – bronchus – trachea – larynx b. bronchiole – bronchus – larynx – trachea – nasal cavity
c. bronchiole – bronchus – trachea – larynx – nasal cavity
d. bronchiole – bronchus – nasal cavity − trachea – larynx
e. bronchiole – trachea – bronchus –larynx – nasal cavity
C. bronchiole- bronchus- trachea- larynx- nasal cavity
201
Accumulated mucus is moved up in the airways to the pharynx by:
a. peristaltic movements of the trachea
b. the movements of cilia on epithelial cells lining the airways
c. the pressure of air flow during normal expiration
d. the vacuum created by a negative pressure during breathing
e. none of the above
B. the movements of cilia on epithelial cells lining the airways
202
A normal inspiration is initiated by the contraction of:
a. abdominal muscles
b. pharyngeal muscles
c. diaphragm
d. intercostal muscles
e. both c and d
E. both c and d
203
Pulmonary surfactant:
a. decreases alveolar surface tension
b. inhibits the diffusion of gases due to partial pressure difference
c. Is produced in abundance during the prenatal period
d. provides an adhesive substance to which inhaled particles stick, preventing their entry into alveoli
e. provides strong adhesion of the alveoli to the partial pleura and chest wall
A. decreases alveolar surface tension
204
The anatomic dead space of the respiratory tract is:
a. the volume of air that cannot be expired from the lung after a maximal expiration
b. the volume of air that never enters the respiratory tract
c. the portion of the respiratory system that is ventilated but never exchanges gases with the blood
d. the portion of the respiratory system that is never ventilated but is perfused with blood
e. the air accumulated in the pleura due to chest wound
C. the portion of the respiratory system that is ventilated but never exchanges gas with the blood
205
An individual with a tidal volume of 600mL, a dead space of 200 mL, and a respiratory rate of 20 breaths per minute would have an alveolar ventilation of:
a. 16,000 mL/min
b. 12,000 mL/min
c. 8,000 mL/min
d. 4000 mL/min
e. 2000 mL/min
c. 8,000 mL/min
206
Oxygen is present in two forms in the blood.
a. bound to hemoglobin and bound to amino acids
b. dissolved in plasma and bound to hemoglobin molecules
c. dissolved in plasma and bound to hemoglobin molecules
d. dissolved in cytoplasm of erythrocytes
e. dissolved in cytoplasm of leukocytes
B. dissolved in plasma bound to hemoglobin molecules
207
The majority of carbon dioxide transported in the blood is in the form of:
a. bicarbonate ions dissolved in blood plasma
b. bicarbonate ions in erythrocytes
c. carbon dioxide bound to hemoglobin
d. carbon dioxide dissolved in blood plasma
e. none of the above
A. bicarbonate ions dissolved in blood plasma
208
Which anatomical structure separates the "entries" into the respiratory and digestive systems?
a. Larynx
b. Nasal cavity
c. Pharynx
d. Trachea
e. Palate
E. Palate
209
Which is the region that warms and moistens the incoming air?
a. Trachea
b. Nasal cavity
c. Pharynx
d. Oral Cavity
e. Larynx
B. Nasal cavity
210
Lung ventilation is different from respiration in that respiration is:
a. the exchange of gases at the level of the lungs
b. the exchange of nutrients at the level of the tissue capillaries
c. actually a synonym for ventilation
d. the process of O2 diffusion in the alveoli
e. complex utilization of O2 for metabolic processes
D. the process of O2 diffusion in the alveoli
211
During inspiration which of the following does not occur?
a. Diaphragm contracts
b. air flows out of the lungs
c. intercostal muscles contract
d. air flows into the bronchioles
e. not all of the air reaches the respiratory membrances
B. air flows out of the lungs
212
The amount of air remaining in the lungs even after the most strenuous expiration is the:
a. tidal volume
b. vital capacity
c. residual volume
d. dead space volume
e. inspiratory reserve volume
C. residual volume
213
The respiratory centres of the brain that control the ventilation of the lungs are located in the _________ and _______:
a. pons, medulla oblongata
b. pons, cerebellum
c. cerebellum, hypothalamus
d. pons, hypothalamus
e. pons, cerebral hemispheres
a. pons, medulla oblongata
