BIO A&P 2 Exam 1 multiple choice study guide
Which cranial nerves decrease heart rate?
vagus nerves
During what phase does blood flow from the ventricles into the pulmonary trunk and aorta?
ventricular ejection phase
Which part of the electrocardiogram (ECG) would most be affected by abnormally slow depolarization of the ventricles?
QRS wave
Upon binding to a receptor to form a hormone-receptor complex, steroid hormones may cause:
an increase in protein synthesis
How do cardiac cells sustain a membrane potential of around 0 mV during the plateau phase?
calcium channels remain open
Autorhythmicity in the heart is the responsibility of:
cardiac pacemaker cells
How are the nervous system and endocrine system similar?
cells of both the nervous system and the endocrine system release chemicals to communicate with the cells
What first tier hormone stimulates cortisol production?
corticotropin-releasing hormone (CRH)
The right side of the heart recieves:
deoxygenated blood from the systemic circuit
A short-term effect of growth hormone is:
fat breakdown
The rapid influx of calcium ions into pacemaker cells creates a positive membrane potential inside the cells and is responsible for the?
full depolarization phase
High levels of testosterone inhibit the release of:
gonadotropin-releasing hormone (GnRH)
All target cells:
have receptors to which hormones bind
Endocrine cells that increase hormone secretion in response to other hormones are controlled by:
hormonal stimuli
Increasing levels of blood glucose stimulate the release of insulin. This type of stimulation is known as:
humoral stimulation
What type of hormone can cross the plasma membrane to bind to a receptor in the cytosol or nucleus?
hydrophobic hormones
Edna complains of weight gain, cold intolerance, and low blood pressure. What disorder do her symptoms match?
hypothyroidism
When blood glucose levels increase, a hormone called insulin is released from endocrine cells in the pancreas. The role of insulin is to return blood glucose levels to normal. Which part of this negative feedback loop is the stimulus?
increasing blood glucose levels
What hormone is the primary antagonist of glucagon?
insulin
What hormone is produced by adipocytes to regulate satiety, a feeling of fullness after eating?
leptin
If the thyroid gland is unable to produce iodinated thyroglobulin, what is the effect on hormone production?
less triiodothyronine (T3) and thyroxine (T4) hormones are made
Which of the following is NOT a population of pacemaker cells in the heart?
papillary muscles
Melatonin is produced by the:
pineal gland
What do pacemaker cells action potentials lack?
plateau phase
A damaged right bundle branch will prevent the passage of the action potential to the:
purkinje fibers in the right ventricle
What is the target tissue of erythropoietin (EPO)?
red bone marrow
What normally serves as the pacemaker of the entire heart?
sinoatrial (SA) node
The volume of blood pumped by each ventricle in one heartbeat is known as
stroke volume (SV)
What two values are needed in order to calculate cardiac output (CO) for a ventricle?
stroke volume (SV) and heart rate (HR)
The effects of norepinephrine and epinephrine have nearly the same effects as the neurotransmitters of the:
sympathetic nervous system
Archie has a resting heart rate of 125 beats per minute. Classify his cardiac dysrhythmia
tachycardia
Predict the position of the valves during the ventricular ejection phase
the AV valves are shut while both semilunar valves are forced open
Determine the impact if the connection between the sinoatrial (SA) node and the atrioventricular (AV) node becomes blocked
the ventricles will contract more slowly
