Past Exam Questions Flashcards

(140 cards)

1
Q

The nervous system can be divided into the central nervous system (CNS), comprised of the:

A

Brain and the spinal cord

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2
Q

The peripheral nervous system is subdivided into sensory or __________ and motor or efferent system

A

afferent

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3
Q

The autonomic nervous system (ANS) is comprised of the parasympathetic (“rest or restore”) and the sympathetic
systems (“fight or flight”)

A

TRUE

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4
Q

These are considered neuroglia cells and provides support to the peripheral and central nervous
system

A
  • schwann cells
  • satellite cells
  • astrocytes
  • ependymal cells
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5
Q

Action potentials only move in one direction along a neuron

A

true

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6
Q

Reflex arcs involve conscious processing in the brain before a response is generated

A

False

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7
Q

Match the neurotransmitter with its primary function:

A
  • muscle contraction: acetylcholine
  • mood regulation: serotonin
  • fight or flight neurotransmitter: adrenalin
  • pleasure transmitter / memory and learning: dopamine
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8
Q

Different than electrical synapses, chemical synapses are sensible to the amount of neurotransmitters present in the synaptic cleft

A

true

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9
Q

Many poisons (such as insecticides, rodenticides, plants, chemicals etc.) can disrupt the function of the nerve
synapse by binding to neurotransmitter receptors on the postsynaptic membranes.
this can lead to:

A
  • blocking information transfer to the postsynaptic cell
  • depolarizing and activating the postsynaptic cell
  • hyperpolarizing and inhibiting the postsynaptic cell

(ALL OF THE ABOVE)

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10
Q

Many poisons (such as insecticides, rodenticides, plants, chemicals etc.) can disrupt the function of the nerve
synapse by deactivating the enzyme that break down the neurotransmitters
this can lead to:

A
  • continuously depolarizing and activating the postsynaptic cell
  • continuously hyperpolarizing and inhibiting the postsynaptic cell

(BOTH B AND C)

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11
Q

Many poisons (such as insecticides, rodenticides, plants, chemicals etc.) can disrupt the function of the nerve
synapse by binding to the neurotransmitter
this can lead to:

A
  • blocking information transer to the postsynaptic cell
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12
Q

Most organs receives instructions from both sympathetic and parasympathetic divisions

A

TRUE

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13
Q

Which is the correct order of the visual pathway?

A
  1. optic nerves
  2. optic chiasma
  3. optic tracts
  4. optic radiations
  5. visual cortex
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14
Q

What is the correct pathway for smell?

A
  1. receptor cells
  2. olfactory nerves (1st pair of cranial nerves)
  3. olfactory bulb
  4. thalamus
  5. olfactory center (CNS)
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15
Q

Classify the general sense receptors:

A
  • pain: nociceptors
  • temperature: thermoreceptors
  • touch/pressure/vibration: tactile receptors
  • blood pressure: baroreceptors
  • chemical concentration: chemoreceptors
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16
Q

What is proprioception primarily related to?

A

awareness of body position and movement

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17
Q

The ____________ triggers the flehmen response in some mammals, which helps direct liquid organic chemicals to the
organ

A

vomeronasal organ

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18
Q

In the context of sensory receptors, what does adaptation refer to?

A

the adjustment of receptors to continuous stimuli

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19
Q

(mark all that apply) The major layers of the eyeball are:

A
  • fibrous layer
  • nervous layer
  • vascular layer
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20
Q

The equilibrium is a mechanical sense that helps the animal maintain its balance by keeping track of the position and
movements of the head

A

TRUE

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21
Q

Local anesthetics can help desensitizing nociceptors by blocking the voltage‐gated potassium channels, therefore
preventing potassium to enter the cell and depolarize

A

FALSE

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22
Q

Match the visual receptors of the eye with the correspondent function

A
  • are light sensitive: rods
  • provides color vision: cones
  • blind spot: optic disc
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23
Q

The vestibular and cochlear branches form the vestibulocochlear nerve, responsible for the equilibrium, and the
information is processed in the cerebellum

A

TRUE

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24
Q

Nystagmus is related to a problem involving the vestibular system in the inner ear or the brain, vertigo, dizziness or
loss of balance are almost always present. This is because the information is distributed to the motor nuclei for
cranial nerves involved with eye, head, and neck movements and to the spinal cord to adjust peripheral muscle tone.
What is the most important cranial nerve related to these clinical signs?

A

vestibulocochlear nerve

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25
The refractory period ensures that action potentials can only travel in one direction along the axon
TRUE
26
The absolute refractory period is the time during which a second action potential can be initiated, but only with a stronger stimulus
FALSE
27
The sodium‐potassium pump is directly responsible for generating the action potential.
false
28
What is the primary characteristic of graded potentials?
they vary in size and duration
29
Which ion is primarily responsible for generating graded potentials in neurons?
Sodium (Na+)
30
What is the role of graded potentials in the initiation of action potentials?
Graded potentials can depolarize the membrane to the threshold and trigger action potentials
31
Which part of a neuron is primarily affected by local anesthetics to block nerve impulses?
Axon terminals
32
What is the primary mechanism of action of local anesthetics?
inhibition of sodium channels
33
Match the correct order of neuroglia cells
- maintenance of the blood-brain barrier: astrocytes - insulation: schwann cells - perform endocytosis: microglia - secrete cerebrospinal fluid: ependymal cells
34
(mark all that apply): The neuroglia cells found in the peripheral nervous system (PNS) are known as:
- schwann cells - satellite cells
35
Match the cell transport function with its correspondent type :
- osmosis: passive transport - facilitated diffusion: passive transport - phagocytosis: active transport - pinocytosis: active transport - receptor-mediated endocytosis: active transport
36
What is the term for the point in the retina where the optic nerve exits, creating a "blind spot" with no photoreceptor cells?
optic disc
37
Dogs possess two types of color‐sensing receptors, called ______________, in their retinas. This makes them similar to most mammals—including cats, cattle and pigs
cones
38
Dogs will perceive some sounds to be louder than humans. Sound vibrations then travel through the inner ear, to a spiral bony chamber called the__________________________, and sound vibrations are converted into electrical signals that the brain can interpret.
cochlea
39
Regarding the homeostatic regulation, a negative feedback occurs when a corrective mechanism opposes or negates a variation from normal limits
true
40
_______(1)___________ conduction is the propagation of action potential along myelinated axons while _________(2)__________ conduction is the propagation of action potential along unmyelinated axons
1. saltatory 2. continuous
41
Which of the following best describes the classification of hormones based on their chemical structure?
peptide, steroid, and amino-acid derived
42
Which of the following hormone classifications is characterized by hormones that are derived from cholesterol?
steroid hormones
43
Amine hormones are freely transported in the bloodstream (hydrophilic) but are unable to penetrate the target cell
true
44
Match the components of the Hypothalamic‐Pituitary‐Adrenal (HPA) axis with their respective functions:
- releases corticotropin-releasing hormone: hypothalamus - secretes adrenocorticotropic hormone (ACTH): anterior pituitary gland (Adenohypophysis) - produces catecholamines such as adrenaline and noraadrenaline: adrenal medulla - releases oxytocin and ADH: posterior pituitary gland (neurohypophysis)
45
Which hormone stimulates the release of thyroid‐stimulating hormone (TSH) from the anterior pituitary gland in response to low levels of thyroid hormones in the bloodstream?
Thyrothropin‐ releasing hormone (TRH)
46
Match the correct order of the oxytocin (OXT) releasing cascade
1. Udder mechanorreceptors (suckling stimuli) 2. OXT release in hypothalamus 3. OXT release in neurohypohysis 4. Myoepithelial cell contraction 5. Teat canal
47
Decreased levels of T3 and T4 in blood, associated to a homeostasis disturbance can be classified as:
hypothyroidism
48
Regarding the thyroid endocrine system, match the following organ with its correspondent function
- synthesis and secretion of TRH: hypothalamus - synthesis and secretion of TSH: adenohypophysis - synthesis and secretion of T3/T4: thyroid gland - thyroxin: mitochondria cell receptor
49
Rusty, a soft‐coated Wheaten Terrier, has a broken talus. In order to heal, his bone cells are starting to reshape the fracture by the action of which hormone and organ?
Parathyroid, which secretes parathormone
50
Which hormone is typically elevated in individuals with Cushing's disease?
cortisol
51
How does blood pressure typically affect the levels of aldosterone in the body?
Lower blood pressure leads to an increase in aldosterone levels
52
In which situation insulin secretion is expected to increase?
after a meal rich in carbohydrates
53
Which of the following is responsible for the storage and release of calcium ions during muscle contraction?
sarcoplasmic reticulum
54
Which molecule blocks the myosin‐binding sites on actin molecules in relaxed muscle?
Tropomyosin
55
What is the process called by which a muscle returns to its original length after contraction?
Relaxation
56
Which structure directly connects the sarcolemma to the sarcoplasmic reticulum in skeletal muscle fibers?
t-tubules
57
Which of the following best describes the role of ATP in muscle contraction?
it hydrolyzes to provide energy for the power stroke of myosin heads
58
A graded potential is responsible for the exocytosis of Ach into the synaptic cleft at the motor end plate, allowing the release of calcium ions at the triads
false
59
Rigor mortis is the stiffening of muscles that occurs after death due to the depletion of ATP, which is needed to release the cross‐bridges between actin and myosin filaments in muscle cells
true
60
_______________ is a polysaccharide composed of glucose molecules and serves as a storage form of glucose in animals, particularly in liver and muscle cells
Glycogen
61
Match the following muscle physiology terms with their descriptions:
- sarcomere: the functional unit of a muscle fiber, consisting of overlapping actin and myosin filaments - motor unit: a single motor neuron and all the muscle fibers it innervates - neuromuscular junction: the point of contact between a motor neuron and a muscle fiber - twitch: a brief contraction of a muscle fiber in response to a single action potential - tetanus: a sustained contraction of a muscle fiber resulting from rapid stimulation of motor neurons
62
Which type of muscle fiber is characterized by a high resistance to fatigue and is rich in mitochondria and myoglobin?
type I (red fibers)
63
The anaerobic metabolism results in the production of ____(1)____ and pyruvate. Despite its fast energy rate, it generates _____(2)____ as a consequence, leading to muscle fatigue
1. ATP 2. lactic acid
64
Aerobic metabolism occurs in the presence of oxygen and primarily takes place in the mitochondria. During aerobic metabolism, pyruvate from glycolysis enters the krebs cycle, where it is converted into acetyl‐coA.
true
65
Which of the following factors influences the force of muscle contraction?
frequency of action potentials from motor neurons
66
Which of the following describes the sliding filament theory of muscle contraction?
myosin filaments slide over each other, shortening the sarcomere
67
Which of the following metabolic pathway primarily provides energy for muscle contraction in resting muscle?
beta-oxidation (fatty acids)
68
Match the following thin filament proteins with its correspondent function
- actin: Contains an active site that can bind to a thick filament - nebulin: Spirals along the actin and hold it together - tropomyosin: Cover the active sites and prevent actinmyosin interaction - troponin: Has a receptor that binds a calcium ion
69
As a whole, a muscle fiber is either contracted or relaxed
true
70
_______(1)________ metabolism is characterized by its efficiency in producing ATP and is primarily utilized during prolonged, low to moderate intensity activities, achieving a total of ___________(2)_______ ATPs regenerated.
1. aerobic 2. 38
71
(check all that apply) These are causes of muscle fatigue are:
- exhaustion of ATP and creatinine-phosphate - drop in pH that accompanies the buildup of lactic acid - physical damage
72
Lactic acid diffuses out of the muscle fibers into the bloodstream and is converted to glucose by the liver
true
73
Order the following steps related to the muscle contraction:
1. exposure of active sites 2. attachment of cross-bridges 3. pivoting 4. detachment of cross-bridges 5. reactivation of myosin
74
What role does acetylcholine play in muscle contraction?
it binds to receptors on the muscle cell membrane, initiating an action potential
75
Match the muscle type fiber with its correspondent property
red fibers (slow-type I) - Small diameter - Small diameter - Small diameter white fiber (fast-type IIb) - High tension -Low myoglobin content - Few mitochondria
76
Match the skeletal, cardiac or smooth muscle with its correspondent property
skeletal muscle: - Multiple nuclei - Filaments are organized in sarcomeres cardiac muscle: - Resistant to fatigue - Contraction without neural stimulation smooth muscle: - Dispersed fibers through sarcoplasm - Have thin filaments attached to dense bodies
77
_____(1)________ muscle fibers have fewer mitochondria and myoglobin, relying more on anaerobic metabolism for short bursts of intense activity, such as sprinting or weightlifting
1. white
78
Match the correct mechanisms of intercellular communication
- Transmitted through the synapses, via neurotransmitters: synaptic communication - Transmitted through the bloodstream, via hormones: endocrine communication - Transmitted through the extracellular fluid, via paracrine factors: paracrine communication - Transmitted through gap junctions, via ions, smalls solutes and lipid soluble materials: direct communication
79
Hormones act in concert, such as epinephrine & norepinephrine. This is known as
synergism
80
(check all that apply) These are considered property of steroid hormones:
- they are hydrophobic - they can bind to mitochondria or nucleus (DNA) - they can increase metabolic activity - are structurally related to cholesterol (ALL THE OPTIONS)
81
The ______(1)_________ pituitary (neurohypophysis) is an extension of the neural tissue, storing and releasing hormones produced in the hypothalamus, while the _________(2)________ pituitary (adenohypophysis) synthesizes and secretes its own hormones under the control of releasing hormones from the hypothalamus
1. posterior 2. anterior
82
ADH (antidiuretic hormone) primarily acts to increase water reabsorption in the kidneys, thereby reducing urine volume
true
83
How does the endocrine system influence cardiac contraction?
by regulating heart rate and contractility through hormones
84
Hormones such as epinephrine and norepinephrine from the adrenal glands, as well as thyroid hormones, can affect cardiac function by altering the rate and force of heart contractions
true
85
Match the following endocrine system cascades with their correct descriptions:
hypothalamic-pituitary thyroid axis - Hypothalamus secretes TRH - Homeostasis of thyroxine hypothalamic-pituitary adrenal axis - Hypothalamus secretes CRH - Anterior hypophysis secretes ACTH
86
In mares, increased melatonin levels during the shorter days of winter signal the onset of the non‐breeding season. How does melatonin influence estrus in these species?
Melatonin inhibits the release of gonadotropins, delaying the onset of estrus
87
The primary target for glucagon action is the liver, promoting gluconeogenesis, and inhibiting glycolisis, to maintain stable glucose levels during fasting
true
88
Order the correct pathway of the HPA‐axis for the releasing of cortisol:
1. Circadian cycle, stress or illness 2. Corticotropin (CRH) releasing hormone 3. Adrenocorticotropic (ACTH) hormone 4. Cortisol and androgens
89
This can be considered an action of the aldosterone hormone
Promotes water retention by Na+ reabsorption
90
(check all that apply) These are considered hormones of the adrenal gland:
- mineralocorticoids - glucocorticoids - androgens
91
Match the valves of the heart with its correspondent location
- right AV valve: tricuspid valve - left AV valve: bicuspid valve - at entrance of pulmonary artery: Pulmonary valve - at entrance of the aorta: aortic valve
92
During ventricular contraction, the atrioventricular valve:
Close to prevent blood flow back into the atria
93
Put the heart impulse conduction in the correct order
1. An action potential is initiated in the SA node 2. Action potentials are conducted from the SA node to the atrial muscle 3. Action travel rapidly through the conduction system to the apex 4. Action potentials spread upward through the ventricular muscle 5. resting state
94
Put the steps of the cardiac cycle in the correct order
1. Atria systole 2. Atrial systole ends 3. Ventricular systole 4. Ventricular ejection 5. Ventricular diastole
95
“Great Duke of Wakanda”, a 10 y.o. Great Dane, has been showing signs of heart problems, and upon clinical examination and inspection, his ECG came out as:
Arrythmia due to ventricular insufficiency
96
Which of the following best describes the normal heart sounds heard in dogs using a stethoscope?
S1 ‐ Lub, S2 ‐ Dub
97
The cardiac output is represented by the following formula: CO (ml/min) = SV (ml/beat) x HR (beats/min), where CO = Cardiac output SV = Stroke volume HR = Heart rate We need to find out what is going on with Mr. Benson, a 5 year‐old American Short‐hair. Calculate the heart rate (HR) (beats/min) for "Mr. Benson", with a cardiac output (CO) of 1500 ml/min and a stroke volume (SV) of 10 ml/beat. With Mr. Benson cardiac output value, we can assume that
Mr. Benson is probably stressed because he is going to the Veterinarian
98
(check all that apply) What are the neural mechanisms for the cardiovascular center?
- cardioacceleratory center - cardioinhibitory center - vasomotor centers
99
Short reflexes are important for
Coordinating local responses to changes in the luminal environment
100
Match the stomach cell with its correspondent function
- Production of mucus: gastric pits - Production and secretion of hydrochloric acid: parietal cells - Production and secretion of pepsinogen: chief cells - Production and secretion of gastrin: G cells
101
When food enters the stomach, the acidic environment triggers the conversion of ____(1)____ into its active form, ____(2)____.
1. pepsinogen 2. pepsin
102
Match the regulation of gastric activity with its correspondent characteristics
the cephalic phase: - Prepare stomach for arrival of food -Neural via preganglionic fibers in vagus nerve the gastric phase: - Homogenize and acidify chyme - Stimulation of gastrin release from G cells the intestinal phase: - Control rate of chyme entry into duodenum - Control rate of chyme entry into duodenum, carbohydrates, and lipids
103
Match the ruminant anatomy parts with its correspondent functions
Rumen: Symbiotic microorganisms, including bacteria, protozoa, and fungi, break down the cellulose and other complex carbohydrates present in the plant material through fermentation reticulum: the larger particles remain in the rumen for further digestion omasum: Absorbs water and nutrients from feed that passes through after its second round of chewing abomasum: Digestive enzymes and hydrochloric acid break down proteins, carbohydrates, and fats into smaller molecules that can be absorbed in the small intestine
104
Enzymes such as pancreatic amylase, lipase, and proteases break down ___(1)____, _______(2)_____ , and ______(3)_____, respectively
1. carbohydrates 2. lipids 3. proteins
105
What is the primary role of cholecystokinin (CCK) in digestion?
Stimulating the release of bile from the gallbladder
106
Match the digestive hormones with its correspondent effects
Cholecystokinin (CCK): Stimulates production of pancreatic enzymes Gastric inhibitory peptide (GIP): Stimulates release of insulin by pancreatic isles Gastrin: Stimulates production of acids and enzymes and increases motility secretin: Inhibits gastric secretion and stimulates production of alkaline buffers
107
Which type of blood cell is primarily responsible for defending the body against infections?
neutrophils
108
Match the correspondent characteristics of the hemoglobin conformation
Oxyhemoglobin: - Bright red - Gases from lungs to peripheral tissues - It is usually transported in high pressure Deoxyhemoglobin: - Dark red - Gases from tissues to lungs - It is found in venules
109
Match the white blood cell type with its correspondent function:
Neutrophil: Phagocytizes microorganisms and other substances Basophil: Releases histamine, promoting inflammation and heparin, which prevents clotting formation Eosinophil: It shows higher cell counts in certain parasitic infections Lymphocyte: Produces antibodies and other chemicals and regulates the immune system Monocyte: Phagocytizes bacteria, dead cells fragments and other debris within tissues
110
Put in the hemostasis event in the correct order
1. A cut triggers vascular spasm, smooth muscles contract, and endothelial cell membranes become "sticky" 2. Attachment of platelets to exposed surfaces, to perform aggregation to form a plug 3. Converts circulating fibrinogen into insoluble fibrin, trapping the blood cells to form a blood clot
111
____(1)______ immunity is _____(2)_____ and provides immediate defense against pathogens upon the first exposure
1. innate 2. nonspecific
112
Which cells are responsible for the production of antibodies in specific immunity?
B cells
113
The constant regions of antibodies determine their class (e.g., IgG, IgM) and effector functions
true
114
Which are the five cardinal signs of inflammation?
1. redness 2. swelling 3. pain 4. warmth 5. some loss of function
115
Pepsinogen is the inactive precursor of the enzyme pepsin, which is secreted by the brush border in the small intestine
false
116
(check all that apply) These are considered major functions of the large intestine
- reabsorption of water - absorption of vitamins produced by bacteria - store fecal material
117
What is the primary function of lipase in digestion?
hydrolyzing triglycerides into fatty acids and glycerol
118
Starches are converted into disacharides into the lumen of the duodenum by the enzyme known as _____(1)____, produced by the pancreas
1. pancreatic amylase
119
(check all that apply) Which of the following statements regarding bile is correct?
- Bile emulsifies lipids, aiding in their digestion and absorption. - Given that horses do not have a gallbladder, bile secretion is continuous
120
No mammal is able to digest cellulose directly
true
121
Which of the following is NOT a product of carbohydrate digestion in the small intestine?
peptides
122
Which cells in the small intestine are responsible for the absorption of amino acids and dipeptides?
Enterocyte cells
123
Allergens are substances that can reset the body's thermostat and raise body temperature
False
124
Match the nonspecific immunity aspects with its correspondent function
Phagocytes: Neutrophils, eosinophils, and macrophages Interferons: Small proteins released by activated immune cells infected with viruses Inflammation: The first step in the healing process, characterized by five cardinal signs Physical barrier: Keep hazardous materials outside of the body Immunological surveillance: Performed by the Natural Killers cells secreting perforin Fever: Proteins, also known as pyrogens, that can raise body temperature complement system: Complements or supplements the action of antibodies
125
During the primary immune response, there is a lag phase before the production of significant amounts of antibodies, while in the secondary response, the response is faster and more robust due to memory B cells.
true
126
Thrombocytes or _____(1)______ play a crucial role in blood clotting by forming clots to prevent excessive bleeding when blood vessels are damaged
platelets
127
Monocytes that moved out of the bloodstream, by diapedesis, are known as ______(1)_____
1. macrophages
128
Match the immune system organ with its correspondent function
Lymph node: It removes debris, pathogens and 99% of antigens Spleen: Remove dead, dying and abnormal erythrocytes Thymus: Final site of T‐cell development Gut‐ associated lymphoid tissue (GALT): An innate apparatus comprised of specialized M cells
129
B cells play a crucial role in vaccine‐induced immunity, as vaccination stimulates the production of memory B cells that can confer protection against future infections
true
130
What role does histamine play in allergic reactions?
It causes vasodilation and increased permeability of blood vessels
131
Which statement accurately describes the bicuspid and tricuspid valves in the heart?
The bicuspid valve is located between the left atrium and left ventricle, while the tricuspid valve is located between the right atrium and right ventricle
132
When blood pressure drops, baroreceptors located in the carotid sinus and aortic arch:
Increase sympathetic activity
133
A heart block is a condition characterized by a delay or interruption in the transmission of electrical signals from the atria to the ventricles . This delay or blockage can occur at various levels of the AV node or the bundle of His, which are the specialized conducting tissues responsible for transmitting impulses between the atria and ventricles. An ECG showing a heart block can be pictured as
third option with blanks
134
The cardioacceleratory center controls the ________(1)______ system (or neurons), increasing heart rate and producing more powerful contractions
1. sympathetic
135
Cardiac output is calculated by multiplying:
stroke volume by heart rate
136
Which factor contributes to the variation in heart rate among different species?
body size and metabolic rate
137
What initiates the depolarization phase of the action potential in contractile cells of the heart?
sodium influx through voltage-gated channels
138
What role does the plateau phase of the action potential serve in cardiac muscle cells?
It allows for sustained contraction by prolonging depolarization
139
Which of the following best describes the action potential duration in cardiac contractile cells compared to skeletal muscle cells?
Longer duration in cardiac contractile cells
140
Blood distribution is a dynamic process that adapts to changing physiological conditions to maintain homeostasis and meet the body's metabolic demands
true