Unit 2 Quizzes
Activation of a (alpha)-adrenergic receptors normally increases blood flow to the skin ventricular contraction vasoconstriction all of the above none of the above
vasoconstriction
Action potentials are normally conducted from your Purkinje fibers directly to your atrioventricular (AV) node sinoatrial (SA) node bundle of His right atrium ventricles
ventricles
During each cardiac cycle, action potentials occur in the bundle of His before they occur in the ventricles atria sinoatrial (SA) node all of the above none of the above
ventricles
On each cycle of heart contraction, an action potential normally occurs in the Purkinje fibers before it occurs in the atria ventricles bundle of His all of the above none of the above
ventricles
Alveolar pressure increases above atmospheric pressure when the internal intercostal muscles contract only at high altitudes as a result of a collapsed lung (pneumothorax) all of the above none of the above
when the internal intercostal muscles contract
Increased secretion of alveolar surfactant would increase surface tension would increase lung compliance is typically caused by Type I alveolar cells all of the above none of the above
would increase lung compliance
The baroreceptor reflex is initiated by a decreased rate of action potentials in baroreceptors causes increased sympathetic nervous system activity involves negative feedback control all of the above none of the above
all of the above
Thin and thick myofilaments slide over one another, shortening the muscle fiber, during contraction of skeletal muscles smooth muscles cardiac muscles all of the above none of the above
all of the above
Which of the following normally causes an increase in ventricular stroke volume? increased acetylcholine secretion increased end-diastolic volume increased peripheral resistance all of the above none of the above
increased end-diastolic volume
Compared to a skeletal muscle fiber action potential, a cardiac muscle cell action potential is briefer has a shorter refractory period involves more sodium ion (Na+) influx all of the above none of the above
none of the above
Cardiac action potentials are normally conducted from Purkinje fibers to the atrioventricular node sinoatrial node bundle of His all of the above none of the above
none of the above
Circulatory shock can be life threatening because blood pressure gets too high the ventricles fill with too much blood the brain receives too much blood all of the above none of the above
none of the above
Compared to fast-glycolytic muscle fibers, slow-oxidative muscle fibers produce more force fatigue faster have more glycolytic enzymes all of the above none of the above
none of the above
Contraction of the diaphragm increases alveolar air pressure (Palv) occurs during expiration (exhalation) occurs due to pacemaker cells in the diaphragm all of the above none of the above
none of the above
Contraction of the diaphragm normally occurs during expiration decreases thoracic volume increases alveolar pressure all of the above none of the above
none of the above
Epinephrine, acting on a (alpha)-adrenergic receptors, causes increased vasodilation heart rate ventricular contractility all of the above none of the above
none of the above
Exchange of oxygen and carbon dioxide between blood capillaries and the airways occurs in the trachea bronchi conducting zone all of the above none of the above
none of the above
When blood pressure is greater in your aorta than your left ventricle, your left semilunar valve opens your left semilunar valve closes your mitral (bicuspid) valve opens your mitral (bicuspid) valve closes
your left semilunar valve closes
Whenever the blood pressure in your aorta becomes higher than the blood pressure in your left ventricle, blood flows from your left ventricle to your left atrium blood flows from your left ventricle to your right ventricle your left semilunar valve closes your mitral valve opens your tricuspid valve opens
your left semilunar valve closes
As a result of your left ventricle filling with more blood on this heart cycle than the last, your tricuspid valve would open sooner your left ventricle would contract more forcefully you would secrete more epinephrine onto your heart all of the above none of the above
your left ventricle would contract more forcefully
You turn the corner on a hiking trail and a bear rises up in front of you. Which of the following is likely to happen? acetylcholine is released onto your heart cells your skeletal muscles receive more blood via activation of b (beta)-adrenergic receptors your parasympathetic activity increases all of the above none of the above
your skeletal muscles receive more blood via activation of b (beta)-adrenergic receptors
Alveolar surfactant is secreted by which cell type? Type I Type II Type III all of the above none of the above
type II
Action potentials occur in autonomic preganglionic neurons cardiac muscle cells skeletal muscle transverse tubules all of the above none of the above
all of the above
Which of the following typically binds to myosin in a skeletal muscle fiber? adenosine triphosphate (ATP) Ca2+ (calcium ions) tropomyosin all of the above none of the above
ATP
If you were exposed to a certain type of bacteria 3 months ago, you probably now have an increased number of a certain type of B cells macrophages erythrocytes all of the above none of the above
B cells
Pollen allergies typically involve delayed hypersensitivity attacks on our lymph nodes by pollen microbes IgE antibodies binding to mast cells all of the above none of the above
IgE antibodies binding to mast cells
Blood capillaries in the central nervous system have smooth muscle connective tissue fenestrations all of the above none of the above
None of the above
Which of the following occurs at the site of a cut during hemostasis? vasodilation nitric oxide is released a fibrin meshwork is formed all of the above none of the above
a fibrin meshwork is formed
Which of the following slows heart rate? epinephrine norepinephrine acetylcholine all of the above none of the above
acetylcholine
Normally, gas exchange between our blood capillaries and our lungs occurs across type I alveolar cells throughout the conducting zone via secondary active transport all of the above none of the above
across type I alveolar cells
An increase in the concentration of hydrogen ions (H+) in your blood plasma would cause an increase in carbon dioxide (CO2) in the blood plasma activation of peripheral chemoreceptors breathing rate and depth all of the above none of the above
all of the above
An increase in the volume of blood filling your ventricles leads to stronger ventricular contraction increased stroke volume increased cardiac output all of the above none of the above
all of the above
An increase in which of the following typically leads to an increase in the amount of oxygen (O2) entering your lungs? the rate of action potentials in your central chemoreceptors the diameter of your bronchioles contraction of your external intercostal muscles all of the above none of the above
all of the above
Antibodies are immunoglobulins are secreted by plasma cells attach to microbes at their variable (Fab) end all of the above none of the above
all of the above
Antibodies are immunoglobulins bind to antigens can occur in as many different kinds as B cells do all of the above none of the above
all of the above
Bone marrow stem cells are capable of directly or indirectly differentiating into (turning into) megakaryocytes erythrocyctes natural killer (NK) cells all of the above none of the above
all of the above
Calcium pumps break down adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and phosphate are in the sarcoplasmic reticulum (SR) membrane move Ca2+ ions into the SR all of the above none of the above
all of the above
Cells in the brainstem medulla generate the rhythm of diaphragm contractions include chemoreceptors increase breathing rate and depth when blood pH decreases all of the above none of the above
all of the above
Compared to fast-glycolytic skeletal muscle fibers, slow-oxidative fibers have more myoglobin enzymes for the Krebs cycle and oxidative phosphorylation blood capillaries around them all of the above none of the above
all of the above
During your prenatal and/or early postnatal life, T lymphocytes (T cells) were generated in your bone marrow migrated to your thymus were killed or inactivated if they bound antigens on your own cells all of the above none of the above
all of the above
Epinephrine increases heart rate acts on b (beta)-adrenergic receptors to cause vasodilation acts on a (alpha)-adrenergic receptors to cause vasoconstriction all of the above none of the above
all of the above
Epinephrine binding to b (beta)-adrenergic receptors normally causes increased heart rate increased ventricular contractility vasodilation all of the above none of the above
all of the above
Epinephrine or norepinephrine, acting on b (beta)-adrenergic receptors, causes an increase in heart rate ventricular contractility skeletal muscle blood flow all of the above none of the above
all of the above
Erythrocytes are generated in bone marrow broken down in the spleen manufactured faster when more erythropoietin is in the blood all of the above none of the above
all of the above
Erythropoietin is secreted by kidney cells causes bone marrow cells to make more erythrocytes is secreted more when living at high altitude all of the above none of the above
all of the above
Fibrin is made from fibrinogen binds to other fibrin molecules is required for blood clotting all of the above none of the above
all of the above
Fibrin is made from fibrinogen mediates blood clotting is produced more when thrombin is secreted all of the above none of the above
all of the above
Gap junctions occur between single-unit smooth muscle cells some stomach muscle cells cardiac cells within an atrium all of the above none of the above
all of the above
Hemostasis normally involves vasoconstriction fibrin molecules binding to each other platelets attaching to each other all of the above none of the above
all of the above
If you vacation in the mountains for two weeks, you will secrete more erythropoietin make more erythrocytes be able to transport more oxygen (O2) in your blood all of the above none of the above
all of the above
Immediate hypersensitivity requires IgE antibodies requires mast cells underlies sneezing in the presence of pollen all of the above none of the above
all of the above
Immunoglobulilns are on the surface of B cells are secreted by plasma cells bind to foreign cells and molecules all of the above none of the above
all of the above
In a skeletal muscle fiber, adenosine triphosphate (ATP) binds to the myosin head provides the energy to change the myosin conformation decreases myosin's affinity for actin all of the above none of the above
all of the above
Natural killer (NK) cells can bind to the Fc ("stem" ) region of immunoglobulins secrete chemicals that kill cells via lysis are part of the nonspecific immune system all of the above none of the above
all of the above
Norepinephrine acts on the heart via b (beta)- adrenergic receptors to increase heart rate to increase ventricular contractility all of the above none of the above
all of the above
Phagocytosis involves endocytosis involves lysosomes can be performed by dendritic cells all of the above none of the above
all of the above
Simultaneous dilation of all your blood vessels happens during a severe immediate hypersensitivity reaction decreases your blood pressure can cause circulatory shock all of the above none of the above
all of the above
Skeletal muscle fibers can use which of the following to synthesize adenosine triphosphate (ATP)? creatine phosphate glycolysis oxidative phosphorylation all of the above none of the above
all of the above
What events happen in normal skeletal muscle contraction before an action potential occurs in a transverse (T) tubule? an endplate potential secretion of acetylcholine a motor neuron action potential all of the above none of the above
all of the above
When metabolism increases in a particular body tissue, that tissue typically produces more heat CO2 (carbon dioxide) H+ (hydrogen ions) all of the above none of the above
all of the above
When you are on the starting line of a track, about to start running a race, your cardiac output increases your blood flow to skeletal muscles increases you use feedforward control all of the above none of the above
all of the above
Which of the following cell types can be produced from bone marrow stem cells? erythrocytes lymphocytes monocytes all of the above none of the above
all of the above
Which of the following is an autoimmune disorder? type I (insulin-dependent) diabetes rheumatoid arthritis multiple sclerosis all of the above none of the above
all of the above
Which of the following is derived from bone marrow stem cells? erythrocytes natural killer cells cytotoxic T cells all of the above none of the above
all of the above
Which of the following is formed directly or indirectly from bone marrow stem cells? erythrocytes leukocytes platelets all of the above none of the above
all of the above
Which of the following is in a thin filament? actin troponin tropomyosin all of the above none of the above
all of the above
Which of the following is true of cardiac pacemaker cells? they can be found in the sinoatrial (SA) node they have channels that allow calcium (Ca2+) through and are opened by depolarization they have channels that allow sodium (Na+) through and are opened by repolarization all of the above none of the above
all of the above
Which of the following is true of immunogloblulins? they are secreted by plasma cells they bind to a particular foreign protein they label foreign cells so complement proteins will attack all of the above none of the above
all of the above
Which of the following is typically part of your nonspecific immune system's response to a viral infection? increased production of neutrophils increased secretion of interferon fever all of the above none of the above
all of the above
Which of the following molecules is typically found in blood? carbon dioxide (CO2) fibrinogen glucose all of the above none of the above
all of the above
Which of the following normally occurs in fever caused by a bacterial infection? interleukin-6 secretion increases the temperature set point in the hypothalamus is increased bacteria secrete endotoxins all of the above none of the above
all of the above
Which of the following typically leads to an increase in cardiac output? standing up after lying down an increase in end-diastolic volume epinephrine all of the above none of the above
all of the above
Which of the following would increase the amount of blood ejected from your ventricles on each cycle? an increase in end-diastolic volume an increase in ventricular contractility activation of b (beta)-adrenergic receptors in the heart all of the above none of the above
all of the above
Which of the following would normally cause increased blood flow to a tissue? opening of precapillary sphincters in the tissue increased arteriolar radius in the tissue increased mean arterial pressure all of the above none of the above
all of the above
Which of the following would normally increase cardiac output? increased contractility increased end-diastolic volume epinephrine all of the above none of the above
all of the above
Which type(s) of muscle fibers are found in your biceps muscle? slow-oxidative fast-oxidative fast-glycolytic all of the above none of the above
all of the above
During skeletal muscle contractions, calcium ions (Ca2+) are moved from the sarcoplasmic reticulum (SR) to the cytosol by calcium pumps allow myosin-binding sites on actin to be exposed bind to myosin and stop contractions all of the above none of the above
allow myosin-binding sites on actin to be exposed
Which of the following would normally cause increased blood flow to a tissue? contraction of vascular smooth muscles in the tissue an increase in blood vessel radius an increase in blood vessel resistance all of the above none of the above
an increase in blood vessel radius
An increase in bicarbonate ions (HCO3-) in your blood plasma would cause your blood plasma to have an increase in carbon dioxide (CO2) a decrease in carbonic acid a decrease in pH all of the above none of the above
an increase in carbon dioxide (CO2)
Which of the following would typically increase the hydrogen ion (H+) concentration (i.e., decrease the pH) of blood plasma? an increase in carbon dioxide production an increase in the rate and/or depth of breathing an increase in synthesis and/or reabsorption of bicarbonate ions (HCO3-) all of the above none of the above
an increase in carbon dioxide production
Which of the following normally causes an increase in cardiac output? vasoconstriction of coronary arteries an increase in end-diastolic volume an increase in peripheral resistance all of the above none of the above
an increase in end-diastolic volume
Which of the following would cause an increase in ventricular stroke volume? an increase in end-diastolic volume an increase in heart rate an increase in peripheral resistance all of the above none of the above
an increase in end-diastolic volume
Which of the following would cause an increase in cardiac output? acetylcholine released onto pacemaker cells an increase in ventricular end-diastolic volume an increase in peripheral resistance all of the above none of the above
an increase in ventricular end-diastolic volume
Which of the following would cause an increase in cardiac output? an increase in ventricular end-diastolic volume decreased cyclic adenosine monophosphate (cAMP) in all cardiac cells acetylcholine binding to muscarinic receptors in the heart all of the above none of the above
an increase in ventricular end-diastolic volume
Blood normally flows from the left ventricle directly to the left atrium right ventricle pulmonary trunk aorta vena cava
aorta
Central chemoreceptors are in the lungs are activated by a decrease in pH (an increase in H+ concentration) in blood or cerebrospinal fluid activate the breathing rhythm generator in the cerebrum all of the above none of the above
are activated by a decrease in pH (an increase in H+ concentration) in blood or cerebrospinal fluid
Central chemoreceptors are activated by an increase in O2 (oxygen) concentration are activated by an increase in H+ (hydrogen ion) concentration are found in the aortic bodies all of the above none of the above
are activated by an increase in H+ (hydrogen ion) concentration
Central chemoreceptors are found on the aorta and carotid artery are activated by low pH are activated by a high partial pressure of oxygen (PO2) all of the above none of the above
are activated by low pH
Major histocompatibility complex (MHC) proteins are required for activation of B lymphocytes (B cells) are made by our own cells are required for antibody secretion all of the above none of the above
are made by our own cells
Cardiac pacemaker cells, but not other cardiac cells, contain ion channels that are opened by depolarization and allow sodium ions (Na+) to pass are opened by repolarization and allow sodium ions (Na+) to pass are opened by depolarization and allow calcium ions (Ca2+) to pass all of the above none of the above
are opened by repolarization and allow sodium ions (Na+) to pass
Platelets are fragments of erythrocytes contain iron atoms attach to each other during hemostasis all of the above none of the above
attach to each other during hemostasis
Most of the oxygen (O2) in your blood is dissolved in blood plasma dissolved in erythrocyte intracellular fluid in erythrocyte mitochondria attached to hemoglobin none of the above
attached to hemoglobin
Without immune tolerance, you would be unable to fight off viruses be unable to fight off bacteria attack your own cells all of the above none of the above
attack your own cells
Adding carbon dioxide (CO2) to the blood within a tissue causes an increase in the local blood concentration of bicarbonate (HCO3-) carbonic anhydrase carbon monoxide (CO) all of the above none of the above
bicarbonate (HCO3-)
In a skeletal muscle, aerobic (endurance) exercise typically increases the number of muscle fibers (muscle cells) glycolytic enzymes blood capillaries all of the above none of the above
blood capillaries
An increase in which of the following would cause a decrease in blood pH? blood carbon dioxide (CO2) blood oxygen (O2) breathing rate and depth all of the above none of the above
blood carbon dioxide (CO2)
Which of the following happens during circulatory shock? blood pressure gets too high peripheral resistance gets too high blood flow to the heart gets too low all of the above none of the above
blood flow to the heart gets too low
What directly causes heart valves to open or close? action potentials in valve muscle cells hormones activating valve muscle cells blood pressure differences on the 2 sides of the valve all of the above none of the above
blood pressure differences on the 2 sides of the valve
Skeletal muscle calcium (Ca2+) pumps bring Ca2+ into the cell from the outside move Ca2+ ions out of the sarcoplasmic reticulum (SR) break down adenosine triphosphate (ATP) all of the above none of the above
break down ATP
Cardiac action potentials involve a net movement of calcium (Ca2+) into the cell sodium (Na+) out of the cell potassium (K+) into the cell all of the above none of the above
calcium into the cell
Antibodies each have two constant regions and one variable region can attach to a foreign cell and mark it for destruction cause allergic reactions to poison ivy all of the above none of the above
can attach to a foreign cell and mark it for destruction
Circulatory shock leads to vasoconstriction throughout your body increases blood pressure to dangerous levels can be caused by a severe allergic reaction all of the above none of the above
can be caused by a severe allergic reaction
Muscle fibers are typically connected via gap junctions within a
cardiac muscle
Muscle fibers are typically connected via gap junctions within a skeletal muscle cardiac muscle multi-unit smooth muscle all of the above none of the above
cardiac muscle
Action potentials have the longest refractory period in which of the following types of cells? neurons skeletal muscle cells cardiac muscle cells
cardiac muscle cells
Ion channels that allow sodium (Na+) to pass through and that open in response to repolarization occur in skeletal muscle cells cardiac contractile cells cardiac pacemaker cells all of the above none of the above
cardiac pacemaker cells
The resistance provided by your blood vessels can be increased by increasing the radius of the blood vessels causes an increase in blood flow rate causes veins to have lower blood pressure than arteries all of the above none of the above
causes veins to have lower blood pressure than arteries
Which of the following is a component of your nonspecific immune system? plasma cells T cells complement proteins all of the above none of the above
complement proteins
Which of the following typically make holes in foreign cells? cytokines complement proteins interleukins all of the above none of the above
complement proteins
Compared to a fast-glycolytic muscle fiber, a slow-oxidative muscle fiber typically produces more force contains more mitochondria has a larger diameter all of the above none of the above
contains more mitochondria
Compared to a fast-glycolytic fiber, each of your slow-oxidative skeletal muscle fibers typically produces more force contains more myoglobin has a larger diameter all of the above none of the above
contains more myoglobin
Which of the following happens latest when a motor neuron activates a skeletal muscle to contract? cross bridges form Ca2+ (calcium) is released from the sarcoplasmic reticulum a transverse tubule action potential a sarcolemma action potential an endplate potential
cross bridges form
You have millions of different receptor types on the surface of your macrophages cytotoxic T cells microglia natural killer (NK) cells basophils
cytotoxic T cells
In your skeletal muscles, adenosine triphosphate (ATP) acts as an allosteric modulator to increase tropomyosin's affinity for actin increase actin's affinity for calcium ions (Ca2+) decrease troponin's affinity for calcium ions (Ca2+) decrease myosin's affinity for actin none of the above
decrease myosin's affinity for actin
Alveolar surfactant is secreted by type I alveolar cells decreases surface tension in alveoli increases hydrogen bonding all of the above none of the above
decreases surface tension in alveoli
Unlike skeletal muscle fibers, smooth muscle fibers have thin and thick filaments do not have troponin do not require calcium ions (Ca2+) for contraction all of the above none of the above
do not have troponin
Ventricular stroke volume is normally increased via a (alpha)-adrenergic receptors by increased total peripheral resistance during exercise all of the above none of the above
during exercise
Blood capillaries normally contain a layer of smooth muscle connective tissue endothelial cells all of the above none of the above
endothelial cells
Which of the following would increase airflow through your airways? histamine epinephrine bronchoconstriction all of the above none of the above
epinephrine
Which of the following would increase the movement of air into your lungs? epinephrine acetylcholine histamine all of the above none of the above
epinephrine
Which of the following typically causes an increase in the diameter of our airways? epinephrine acting on a- (alpha-) adrenergic receptors epinephrine acting on b- (beta-) adrenergic receptors inflammation all of the above none of the above
epinephrine acting on b- (beta-) adrenergic receptors
An increase in erythropoietin secretion causes increased production of
erythrocytes
Which of the following causes increased production of red blood cells? thrombin fibrinogen erythropoietin all of the above none of the above
erythropoietin
During hemostasis, fibrin binds to
fibrin
Which of the following is a protein involved in blood clotting? fibrin hemoglobin platelets all of the above none of the above
fibrin
Which of the following is involved in forming a blood clot? albumin fibrin hemoglobin all of the above none of the above
fibrin
Which of the following occurs in cardiac muscle but not in skeletal muscle? gap junctions filaments sliding over each other calcium binding to troponin all of the above none of the above
gap junctions
Presentation of a foreign antigen combined with a type II major histocompatibility complex (MHC) protein is required to activate natural killer cells cytotoxic T cells helper T cells all of the above none of the above
helper T cells
Which of the following is a component of your specific immune system? interferons helper T cells macrophages all of the above none of the above
helper T cells
Intrapleural fluid normally is inside the lungs has a pressure that is greater than alveolar pressure helps keep the lungs from collapsing all of the above none of the above
helps keep the lungs from collapsing
Fever helps kill bacteria involves short-term damage to your hypothalamus is a failure of temperature regulation all of the above none of the above
helps kill bacteria
Mature human erythrocytes contain hemoglobin mitochondria a nucleus all of the above none of the above
hemoglobin
The left semilunar valve closes whenever the blood pressure is higher in the left ventricle than in the left atrium higher in the left atrium than in the left ventricle higher in the aorta than in the left ventricle higher in the left ventricle than in the aorta none of the above
higher in the aorta than in the left ventricle
The mitral (bicuspid) valve closes when blood pressure is higher in the aorta than in the left ventricle higher in the left ventricle than in the aorta higher in the left atrium than in the left ventricle higher in the left ventricle than in the left atrium none of the above
higher in the left ventricle than in the left atrium
The right semilunar valve opens when blood pressure is higher in the right atrium than the right ventricle higher in the right ventricle than the right atrium higher in the right ventricle than the pulmonary trunk higher in the pulmonary trunk than the right ventricle none of the above
higher in the right ventricle than the pulmonary trunk
The major histocompatibility complex (MHC) proteins that our T cells bind to (when attached to foreign antigen fragments) are made by viruses bacteria human cells all of the above none of the above
human cells
Interferons are typically secreted by bacteria human cells that have been attacked by bacteria human cells that have been attacked by viruses all of the above none of the above
human cells that have been attacked by viruses
Your immune system normally doesn't attack your own cells because your genome only codes for immune receptors that target foreign antigens your own cells secrete a chemical that inhibits attack by immune cells immune cells that bind to your own proteins were eliminated or inactivated in early development all of the above none of the above
immune cells that bind to your own proteins were eliminated or inactivated in early development
An increase in oxygen delivery to all your tissues typically can be caused by increased production of 2,3-bisphosphoglycerate (2,3-BPG or 2,3-DPG) in erythrocytes increased activation of the diaphragm muscle pacemaker cells increased acetylcholine binding to muscarinic receptors on bronchiolar circular muscles all of the above none of the above
increased production of 2,3-bisphosphoglycerate (2,3-BPG or 2,3-DPG) in erythrocytes
An increase in blood vessel diameter increases blood flow through that vessel increases resistance through that vessel can be caused by vasopressin (antidiuretic hormone or ADH) all of the above none of the above
increases blood flow through that vessel
Which of the following is a molecule that inhibits reproduction of viruses? megakaryocyte factor XIII interferon all of the above none of the above
interferon
Which of the following is a protein that slows viral reproduction? antigen interferon antibiotic neutrophil lymphocyte
interferon
Pollen allergies involve production of IgE antibodies protect us from toxic flowers are caused by histamine inside the pollen granules all of the above none of the above
involve production of IgE antibodies
Phagocytosis can be performed by interferons involves binding of immune cell receptors to foreign nucleic acids involves lysosomes digesting foreign proteins all of the above none of the above
involves lysosomes digesting foreign proteins
Alveolar surfactant is amphipathic increases bonding of water molecules to each other is secreted by type I alveolar cells all of the above none of the above
is amphipathic
An increase in thoracic volume typically is caused by contraction of the diaphragm causes an increase in lung alveolar pressure occurs during expiration all of the above none of the above
is caused by contraction of the diaphragm
Actin can hydrolyze adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and phosphate is part of a thin filament has a head and a tail all of the above
is part of a thin filament
Antigen presentation is required to activate T lymphocytes (T cells) involves an attack on foreign major histocompatibility (MHC) proteins requires antibodies all of the above none of the above
is required to activate T lymphocytes (T cells)
During skeletal muscle contractions, adenosine triphosphate (ATP) is required to change the conformation (shape) of myosin increases the affinity of myosin for actin binds to troponin all of the above none of the above
is required to change the conformation (shape) of myosin
Erythropoietin increases leukocyte production increases heart rate is secreted by the kidneys all of the above none of the above
is secreted by the kidneys
An increase in the volume of our lungs is typically caused by contraction of the diaphragm occurs during exhalation (expiration) typically causes alveolar pressure to become less than intrapleural pressure all of the above none of the above
is typically caused by contraction of the diaphragm
Compared to slow-oxidative muscle fibers, fast-glycolytic fibers have larger diameters more blood capillaries around them more myoglobin in them all of the above none of the above
large diameters
Which of the following might cause circulatory shock? large systemic vasodilation a sudden increase in cardiac output a sudden increase in blood pressure all of the above none of the above
large systemic vasodilation
Blood flows from the left atrium directly into the
left ventricle
The left semilunar valve normally opens whenever blood pressure is higher in the left atrium than the left ventricle left ventricle than the left atrium left ventricle than the right ventricle left atrium than the pulmonary artery left ventricle than the aorta
left ventricle than the aorta
Flow of blood back to your heart is increased by opening of pre-capillary sphincter muscles one-way valves in your arteries leg skeletal muscle contractions all of the above none of the above
leg skeletal muscle contractions
The pressure of your intrapleural fluid is normally greater than alveolar pressure less than alveolar pressure the same as alveolar pressure
less than alveolar pressure
If we doubled the concentration of calcium ions (Ca2+) in the sarcoplasmic reticulum of your skeletal muscles, this would cause rigor mortis absence of muscle contractions smaller muscle contractions briefer muscle contractions longer-lasting muscle contractions
longer-lasting muscle contractions
Which of the following is greater during expiration (exhalation) than during inspiration (inhalation)? lung volume lung air pressure (Palv) contraction of the diaphragm all of the above none of the above
lung air pressure (Palv)
Which of the following is a type of cell? platelet immunoglobulin lymphocyte all of the above none of the above
lymphocyte
Which of the following is a component of the nonspecific immune system? macrophages B lymphocytes (B cells) T lymphocytes (T cells) all of the above none of the above
macrophages
A decrease in the diameter of an arteriole is called vasodilation may be caused by contraction of smooth muscles increases blood flow through that arteriole all of the above none of the above
may be caused by contraction of smooth muscles
Central chemoreceptors are found in your bronchi carotid arteries medulla all of the above none of the above
medulla
The rate of diaphragm contractions during breathing is determined by cells in your cerebral cortex cerebellum medulla autonomic ganglia diaphragm
medulla
The timing of breathing is determined by the cerebrum cerebellum medulla diaphragm interstitial cells of Cajal
medulla
If you have previously had a particular bacterial disease or had a vaccine for that disease, you will typically have new types of antigen receptors on your B cells more B cells with receptors that bind to that kind of bacteria more cytokines that bind to that kind of bacteria all of the above none of the above
more B cells with receptors that bind to that kind of bacteria
Adenosine triphosphate (ATP) is required in skeletal muscle fibers to move the myosin head to its high-energy conformation unblock the myosin binding site on the thin filaments increase the affinity of myosin for actin, so cross-bridges can form all of the above none of the above
move the myosin head to its high-energy conformation
Which of the following represents a failure of immune self-tolerance? multiple sclerosis acquired immune deficiency syndrome (AIDS) allergies all of the above none of the above
multiple sclerosis
Which of the following typically happens as a result of weight lifting? muscles get more muscle fibers muscle fibers get thicker muscle fibers get more enzymes for oxidative phosphorylation all of the above none of the above
muscle fibers get thicker
Which of the following is a component of your nonspecific immune system? T lymphocytes (T cells) natural killer (NK) cells immunoglobulins all of the above none of the above
natural killer (NK) cells
Which of the following kills invading microbes by secreting toxic chemicals directly onto them? megakaryocytes B cells natural killer cells all of the above none of the above
natural killer cells
Which of the following types of cells typically engages in phagocytosis? erythrocytes neutrophils megakaryocytes all of the above none of the above
neutrophils
Which of the following typically engages in phagocytosis? neutrophils interleukins megakaryocytes all of the above none of the above
neutrophils
The neurotransmitter released by motor neurons onto skeletal muscle fibers acts on a (alpha)-adrenergic receptors b (beta)-adrenergic receptors nicotinic aceylcholine receptors muscarinic aceylcholine receptors none of the above
nicotinic aceylcholine receptors
Which of the following typically causes vasodilation? norepinephrine acting on a (alpha)-adrenergic receptors nitric oxide angiotensin II all of the above none of the above
nitric oxide
An increase in the air pressure in your lungs (alveolar pressure) above atmospheric pressure normally occurs when the volume of your lungs increases during inspiration (inhalation) when the diaphragm contracts all of the above none of the above
none of the above
Antibodies are secreted by antigens T lymphocytes (T cells) macrophages all of the above none of the above
none of the above
As a result of adenosine triphosphate (ATP) binding to a myosin head in a skeletal muscle fiber myosin's affinity for actin increases tropomyosin is pulled off of actin calcium is released from the sarcoplasmic reticulum all of the above none of the above
none of the above
In your skeletal muscles, adenosine triphosphate (ATP) acts as an allosteric modulator to increase tropomyosin's affinity for actin actin's affinity for calcium (Ca2+) myosin's affinity for actin all of the above none of the above
none of the above
Which of the following is a part of the thick filaments in your skeletal muscle fibers? actin troponin tropomyosin all of the above none of the above
none of the above
Which of the following occurs during blood clotting? vasodilation at the site of injury fibrinogen is formed from fibrin erythrocytes are broken to form platelets all of the above none of the above
none of the above
Which of the following normally causes an increase in heart rate? acetylcholine binding to muscarinic receptors on heart cells epinephrine binding to a (alpha)-adrenergic receptors on heart cells norepinephrine binding to b (beta)-adrenergic receptors on heart cells all of the above none of the above
norepinephrine binding to b (beta)-adrenergic receptors on heart cells
In your skeletal muscles, adenosine triphosphate (ATP) acts as an allosteric modulator to increase
not myosin affinity to actin
Endurance (aerobic) exercise typically affects your skeletal muscles by increasing the number of mitochondria number of muscle fibers (cells) speed of the myosin ATPases all of the above none of the above
number of mitochondria
Phagocytosis requires immunoglobulins involves complement proteins occurs in your brain all of the above none of the above
occurs in your brain
Movement of substances from blood vessels into brain interstitial fluid normally occurs only from capillaries includes cells includes most blood proteins all of the above none of the above
occurs only from capillaries
You normally breathe in and out with a regular rhythm because of pacemaker potentials in cells of your diaphragm of neurons in your medulla that produce a rhythmic output you learned to breathe this way as a child all of the above none of the above
of neurons in your medulla that produce a rhythmic output
During a typical cycle of heart contraction, ventricular pressure decreases as a result of opening of the semilunar valves opening of the atrioventricular valves atrial contraction ventricular contraction none of the above
opening of semilunar valves
If you have pollen allergies, it is because your immune system doesn't respond quickly enough attacks your own cells (i.e., an autoimmunity) overproduces IgE antibodies all of the above none of the above
overproduces IgE antibodies
Natural killer (NK) cells secrete perforins antibodies leukocytes all of the above none of the above
perforins
Which of the following directly kills foreign cells? perforins thrombin cytokines helper T cells B cells
perforins
Which of the following makes antibodies? T cells neutrophils plasma cells all of the above none of the above
plasma cells
In response to an infection by a microbe that your body has never encountered before, which of the following typically happens before antibodies are secreted? B cells are activated by antigen presentation plasma cells are generated natural killer cells attach to the stem (Fc) end of the antibodies all of the above none of the above
plasma cells are generated
During an allergic reaction to pollen, pollen microbes attack your lungs T cells attack the pollen pollen binds to IgE antibodies all of the above none of the above
pollen binds to IgE antibodies
Which of the following is an autoimmune disorder? type I (insulin-dependent) diabetes mellitus Huntington's disease acquired immune deficiency syndrome (AIDS) all of the above none of the above
type I (insulin-dependent) diabetes mellitus
Which of the following happens during both skeletal muscle fiber action potentials and cardiac action potentials? calcium (Ca2+) channels open in response to repolarization potassium (K+) channels open in response to depolarization there is a refractory period of about 250 msec all of the above none of the above
potassium (K+) channels open in response to depolarization
Immune self-tolerance is normally acquired at which stage of life? conception prenatal development puberty adulthood none of the above
prenatal development
Alveolar surfactant is secreted by type 1 alveolar cells increases surface tension prevents alveoli from collapsing all of the above none of the above
prevents alveoli from collapsing
The refractory period of cardiac cell action potentials is shorter than the refractory period of skeletal muscle cells is due to prolonged influx of sodium ions prevents the heart from beating faster than about 4 times/second all of the above none of the above
prevents the heart from beating faster than about 4 times/second
Antigen presentation requires major histocompatibility complex (MHC) proteins is required for activation of B lymphocytes (B cells) is required for antibody secretion all of the above none of the above
requires major histocompatibility complex (MHC) proteins
In which of the following locations do action potentials occur earliest within each heart cycle? right Purkinje fibers right ventricle right sinoatrial node left sinoatrial node left bundle of His
right SA node
The diaphragm separates the thorax from the abdomen is a smooth muscle contracts during expiration all of the above none of the above
separates the thorax from the abdomen
During exercise, there is increased blood flow to skeletal muscles the liver the stomach all of the above none of the above
skeletal muscles
Which of the following is normally activated to contract as a result of acetylcholine binding to nicotinic receptors? skeletal muscles smooth muscles cardiac muscles all of the above none of the above
skeletal muscles
Memory T cells are part of the nervous system produce new kinds of membrane receptors following an infection survive as a clone of identical cells following an infection all of the above none of the above
survive as a clone of identical cells following an infection
When you stand up suddenly, there is an increase in the rate of action potentials in arterial baroreceptors mean arterial blood pressure sympathetic outflow all of the above none of the above
sympathetic outflow
Which is a part of the respiratory zone? the trachea the bronchi the alveoli all of the above none of the above
the alveoli
On each cardiac cycle, in which of the following locations do action potentials occur earliest? the bundle of His the Purkinje fibers the ventricles the septum the atrioventricular (AV) node
the atrioventricular (AV) node
Fever often occurs during a bacterial infection because the body temperature set point is changed in the hypothalamus the large number of bacterial cells generate excess heat the large number of immune system cells generate excess heat all of the above none of the above
the body temperature set point is changed in the hypothalamus
During circulatory shock, blood pressure gets dangerously high there is massive vasoconstriction throughout the body the heart and brain do not receive enough blood all of the above none of the above
the heart and brain do not receive enough blood
Circulatory shock can be life threatening because blood pressure gets too high the heart does not receive enough oxygenated blood heart rate is too fast to allow sufficient ventricular filling all of the above none of the above
the heart does not receive enough oxygenated blood
Which normally has the lowest pressure? the trachea the bronchi the bronchioles the alveoli the intrapleural fluid
the intrapleural fluid
On each cardiac cycle, action potentials occur earliest in the bundle of His the right ventricle the Purkinje fibers the left atrium the aorta
the left atrium
An increase in secretion of erythropoietin would cause an increase in blood clotting blood pressure the number of erythrocytes all of the above none of the above
the number of erythrocytes
Regular strenuous exercise (e.g., weight lifting) leads to an increase in the number of muscle fibers the number of filaments within muscle fibers the amount of oxidative enzymes in muscle fibers all of the above none of the above
the number of filaments within muscle fibers
When you go from resting to doing strenuous exercise, the percentage of blood ejected from your ventricles goes from about 60% to about 90% your heart rate becomes about 6 times as fast your blood pressure becomes about 4 times as high all of the above none of the above
the percentage of blood ejected from your ventricles goes from about 60% to about 90%
During excitation of a skeletal muscle fiber, an action potential begins last in the transverse tubules the motor neuron axon the muscle fiber sarcolemma the thin filaments the thick filaments
the transverse tubules
When you voluntarily contract a muscle, an action potential occurs in a muscle fiber's sarcolemma before transverse (T) tubules have action potentials a motor neuron has an action potential the muscle fiber has an endplate potential all of the above none of the above
transverse (T) tubules have action potentials
When a muscle cell is relaxed, which of the following blocks binding sites necessary for muscle contraction? actin myosin tropomyosin troponin calcium
tropomyosin
When a skeletal muscle fiber is at rest, most of the myosin-binding sites on actin are blocked by
tropomyosin
Normally when a skeletal muscle fiber is relaxed, tropomyosin blocks the myosin-binding sites on actin calcium (Ca2+) is bound to myosin adenosine triphosphate (ATP) is bound to actin all of the above none of the above
tropomyosin blocks the myosin-binding sites on actin
