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Example Questions
Example Question #51 : Endocrine System
Which of the following hormones is not synthesized in the pituitary gland?
Growth hormone
Prolactin
Oxytocin
Adrenocorticotropic hormone
Oxytocin
Oxytocin is the only hormone mentioned that is synthesized in the hypothalamus, but secreted by the posterior pituitary.
Example Question #655 : Systems Biology And Tissue Types
There are a large variety of over-the-counter pregnancy tests, although all of them share a set of common principles.
These home pregnancy tests are immunoassays which detect the presence of the peptide hormone human chorionic gonadotropin (hCG). hCG is produced by the fertilized ovum and released into the mother's bloodstream, preventing the degradation of the corpus luteum and thereby preventing menstruation. By the time of the mother's first missed period, hCG levels in the urine are high enough to detect.
The home pregnancy test generally involves dipping a stick containing immobilized hCG monoclonal antibodies into a urine sample. If hCG is present in the urine, it will bind to the monoclonal antibodies on the dipstick. The dipstick is then placed in a solution containing a second monoclonal antibody which recognizes the bound hCG antibody complex on the surface of the dipstick. This second antibody is conjugated to colloidal gold particles which change color when they are immobilized, indicating a positive test result (i.e., pregnancy).
As described in the passage, the home pregnancy test __________.
is only effective after at least one month of pregnancy
is inaccurate because hCG is sometimes not produced by the fertilized zygote
accuracy improves when administered during early morning hours
lacks positive and negative controls
is inaccurate because hCG can be produced normally in the non-pregnant mother
lacks positive and negative controls
The test, as described in the passage, simply assays for the presence of hCG in the urine. The person using the test would either obtain a positive or negative result. Whether or not this result is valid remains in question because there are no experimental controls involved. In other words, there is nothing to test whether the test reagents are faulty or the procedure was done incorrectly. A positive control would involve using a sample liquid containing hCG and testing to see whether the pregnancy test could actually detect it. If it can't, then something is wrong. A negative control might involve using a urine sample with no hCG in it and seeing if the test gives a false positive result. Such controls are not included in the test as described in the passage. The other answer choices can be eliminated. The answer: 'is only effective after at least one month of pregnancy' is wrong because the passage states that hCG levels are high enough to be detected by the time of the first missed period (anywhere from 7-14 days from the time of fertilization.)
The answer: 'is inaccurate because hCG can be produced normally in the non-pregnant mother,' can be eliminated because the mother does not produce hCG. If she did, the test would be entirely useless. Only the embryo produces the hormone. The answer choice, 'is inaccurate because hCG is sometimes not produced by the fertilized zygote,' is also incorrect because the embryo must produce hCG in order to prevent menstruation and maintain the corpus luteum. If it doesn't, menstruation will occur and the embryo will be sloughed off with the uterine lining.
Example Question #656 : Systems Biology And Tissue Types
There are a large variety of over-the-counter pregnancy tests, although all of them share a set of common principles.
These home pregnancy tests are immunoassays which detect the presence of the peptide hormone human chorionic gonadotropin (hCG). hCG is produced by the fertilized ovum and released into the mother's bloodstream, preventing the degradation of the corpus luteum and thereby preventing menstruation. By the time of the mother's first missed period, hCG levels in the urine are high enough to detect.
The home pregnancy test generally involves dipping a stick containing immobilized hCG monoclonal antibodies into a urine sample. If hCG is present in the urine, it will bind to the monoclonal antibodies on the dipstick. The dipstick is then placed in a solution containing a second monoclonal antibody which recognizes the bound hCG antibody complex on the surface of the dipstick. This second antibody is conjugated to colloidal gold particles which change color when they are immobilized, indicating a positive test result (i.e., pregnancy).
The mechanism by which hCG acts on its target cells is most similar to that of __________.
aldosterone
glucagon
testosterone
progesterone
estradiol
glucagon
From the passage we learn that hCG is a peptide hormone. Peptide hormones act by binding to receptors on the plasma membranes of their target cells. This binding then triggers a signaling cascade which results in the transcription of specific genes. Peptide hormones can't cross the plasma membrane directly because they are not lipid soluble. Glucagon is a peptide hormone secreted by the alpha cells of the pancreas; it therefore uses a similar mechanism to that of hCG.The other answer choices can be eliminated because they are steroid hormones. These act by directly crossing the plasma membrane and binding to receptors either in the cytoplasm or in the nucleus.
Example Question #657 : Systems Biology And Tissue Types
There are a large variety of over-the-counter pregnancy tests, although all of them share a set of common principles.
These home pregnancy tests are immunoassays which detect the presence of the peptide hormone human chorionic gonadotropin (hCG). hCG is produced by the fertilized ovum and released into the mother's bloodstream, preventing the degradation of the corpus luteum and thereby preventing menstruation. By the time of the mother's first missed period, hCG levels in the urine are high enough to detect.
The home pregnancy test generally involves dipping a stick containing immobilized hCG monoclonal antibodies into a urine sample. If hCG is present in the urine, it will bind to the monoclonal antibodies on the dipstick. The dipstick is then placed in a solution containing a second monoclonal antibody which recognizes the bound hCG antibody complex on the surface of the dipstick. This second antibody is conjugated to colloidal gold particles which change color when they are immobilized, indicating a positive test result (i.e., pregnancy).
Why isn't the presence of progesterone used as an indicator of pregnancy in the home pregnancy test?
Progesterone is continuously secreted by the adrenal gland and the levels are not subject to any alterations as a result of pregnancy
Progesterone is not made exclusively by the fertilized zygote
Progesterone is not present in the bloodstream
Progesterone is secreted too late in the pregnancy to be of any diagnostic value
All of these
Progesterone is not made exclusively by the fertilized zygote
In order to be indicative of pregnancy, a hormone must only be produced either by a mother who is pregnant or the fertilized embryo itself. Otherwise, false test results might be possible. Progesterone is normally produced by females who are not pregnant during the course of their monthly menstrual cycles. It is not purely a hormone associated with pregnancy. The other answer choices do not offer valid explanations why progesterone can't be used.
Example Question #21 : Hormones
Both the sympathetic and the parasympathetic nervous systems are essential for homeostasis and for survival. For example, when we are trying to run away from a threat, the sympathetic nervous system is in full effect to allow us to escape from danger. However, when there is no obvious threat, the parasympathetic nervous system tends to be more in control.
There are similarities and differences between the sympathetic and the parasympathetic nervous systems. In preganglionic nerve fibers, both the sympathetic and the parasympathetic nervous system utilize the neurotransmitter acetylcholine. Closer to the target organ, the parasympathetic nervous system remains dependent on acetylcholine whereas norepinephrine and epinephrine are the predominant neurotransmitters utilized by the sympathetic nervous system.
When norepinephrine and epinephrine bind to their receptors, different effects are carried out based on the type of receptor, affinity, and location of the receptor. For example, epinephrine has a higher affinity for the beta-2 receptor. When epinephrine binds to the beta-2 receptor, common effects include vasodilation and bronchodilation. Norepinephrine has a stronger affinity for the alpha-1, alpha-2 and beta-1 receptors. When norepinephrine binds to its receptor, common effects on the body include vasoconstriction (alpha-1), increased heart rate (beta-1) and uterine contraction (alpha-1).
Patient A has a genetic disorder which prevents him from producing sufficient amount of catecholamines. Which of the following events will be affected in this patient.
I. Digestion
II. Pupil dilation
III. Erection
I and II
II and III
II only
III only
I only
II only
Catecholamines consist of epinephrine and norepinephrine. Without these neurotransmitter, the nervous system cannot illicit a sympathetic response. Of the answer choices, only pupil dilation is an event mediated by the sympathetic nervous system.
Example Question #21 : Hormones
The brain is a very delicate structure with little room to move around. Surrounding the brain and the spinal cord are three protective layers in addition to the skull and the vertebral column. Directly surrounding the brain and spinal cord is the pia mater. Following the pia mater is the arachnoid mater. Between the pia mater and the arachnoid mater is the sub-arachnoid space where the cerebrospinal fluid circulates. Finally, the protective layer is the dura mater is loosely attached to the arachnoid mater but is strongly associated with the skull bone.
Depending on the type of injury, a certain type of vein and/or artery are more susceptible to injury. For example, the meningeal artery and vein run through the foramen spinosum and travel between the two layers making up the dura mater. As the artery and the vein are traveling in between the dura mater, there is a vulnerable region at the temple. A strike to the temple region could rupture these vessels and result in a epidural hematoma.
Traveling from the cerebral cortex to the venous dural sinus (located at certain regions between the two layers of the dura mater) is the cerebral vein. When an injury results in the dura mater shifting away from the arachnoid mater, the cerebral vein could rupture and lead to a subdural hematoma.
During a hematoma, the intercranial pressure could increase and push on certain regions of the brain. The compression of a certain region could either excite or inhibit the area. If patient A's laboratory results showed an increase blood concentration of antidiuretic hormone, which region of the brain is being compressed?
Adrenal gland
Posterior pituitary
Anterior pituitary
Optic chiasm
Cerebral cortex
Posterior pituitary
Antidiuretic hormone is produced by the hypothalamus and is released by the posterior pituitary. Therefore, compression either of these structures could provoke the release of antidiuretic hormone.
Example Question #22 : Hormones
The brain is a very delicate structure with little room to move around. Surrounding the brain and the spinal cord are three protective layers in addition to the skull and the vertebral column. Directly surrounding the brain and spinal cord is the pia mater. Following the pia mater is the arachnoid mater. Between the pia mater and the arachnoid mater is the sub-arachnoid space where the cerebrospinal fluid circulates. Finally, the protective layer is the dura mater is loosely attached to the arachnoid mater but is strongly associated with the skull bone.
Depending on the type of injury, a certain type of vein and/or artery are more susceptible to injury. For example, the meningeal artery and vein run through the foramen spinosum and travel between the two layers making up the dura mater. As the artery and the vein are traveling in between the dura mater, there is a vulnerable region at the temple. A strike to the temple region could rupture these vessels and result in a epidural hematoma.
Traveling from the cerebral cortex to the venous dural sinus (located at certain regions between the two layers of the dura mater) is the cerebral vein. When an injury results in the dura mater shifting away from the arachnoid mater, the cerebral vein could rupture and lead to a subdural hematoma.
During a hematoma, the intercranial pressure could increase and push on certain regions of the brain. The compression of a certain region could either excite or inhibit the area. If patient A's laboratory results showed an increase blood concentration of antidiuretic hormone, which region(s) of the brain could be compressed?
I. Posterior pituitary
II. Anterior pituitary
III. Hypothalamus
I only
I and III
III only
III only
II and III
I and III
Antidiuretic hormone is produced by the hypothalamus and is released by the posterior pituitary. Therefore, compression either of these structures could result in increased blood concentrations of antidiuretic hormone.
Example Question #23 : Hormones
The brain is a very delicate structure with little room to move around. Surrounding the brain and the spinal cord are three protective layers in addition to the skull and the vertebral column. Directly surrounding the brain and spinal cord is the pia mater. Following the pia mater is the arachnoid mater. Between the pia mater and the arachnoid mater is the sub-arachnoid space where the cerebrospinal fluid circulates. Finally, the protective layer is the dura mater is loosely attached to the arachnoid mater but is strongly associated with the skull bone.
Depending on the type of injury, a certain type of vein and/or artery are more susceptible to injury. For example, the meningeal artery and vein run through the foramen spinosum and travel between the two layers making up the dura mater. As the artery and the vein are traveling in between the dura mater, there is a vulnerable region at the temple. A strike to the temple region could rupture these vessels and result in a epidural hematoma.
Traveling from the cerebral cortex to the venous dural sinus (located at certain regions between the two layers of the dura mater) is the cerebral vein. When an injury results in the dura mater shifting away from the arachnoid mater, the cerebral vein could rupture and lead to a subdural hematoma.
During a hematoma, the intracranial pressure could increase and push on certain regions of the brain. The compression of a certain region could either excite or inhibit the area. If patient A has been diagnosed with Cushing's syndrome (excess cortisol), which region(s) could be compressed?
Posterior pituitary
Pineal gland
Adrenal medulla
Anterior pituitary
Adrenal cortex
Anterior pituitary
The anterior pituitary releases adrenocorticotropic hormone (ACTH). ACTH then binds receptors in the adrenal cortex and promotes the release of cortisol.
Example Question #24 : Hormones
The brain is a very delicate structure with little room to move around. Surrounding the brain and the spinal cord are three protective layers in addition to the skull and the vertebral column. Directly surrounding the brain and spinal cord is the pia mater. Following the pia mater is the arachnoid mater. Between the pia mater and the arachnoid mater is the sub-arachnoid space where the cerebrospinal fluid circulates. Finally, the protective layer is the dura mater is loosely attached to the arachnoid mater but is strongly associated with the skull bone.
Depending on the type of injury, a certain type of vein and/or artery are more susceptible to injury. For example, the meningeal artery and vein run through the foramen spinosum and travel between the two layers making up the dura mater. As the artery and the vein are traveling in between the dura mater, there is a vulnerable region at the temple. A strike to the temple region could rupture these vessels and result in a epidural hematoma.
Traveling from the cerebral cortex to the venous dural sinus (located at certain regions between the two layers of the dura mater) is the cerebral vein. When an injury results in the dura mater shifting away from the arachnoid mater, the cerebral vein could rupture and lead to a subdural hematoma.
During a hematoma, the intracranial pressure could increase and push on certain regions of the brain. The compression of a certain region could either excite or inhibit the area. If the hematoma is compressing on the anterior pituitary, which of the following hormone(s) could be found in excess in the blood?
I. Antidiuretic hormone (ADH)
II.Oxytocin
III. Follicle-stimulating hormone (FSH)
II and III
I only
I, II, and III
III only
III only
III only
Of the answer choices, only FSH is released by the anterior pituitary. To help remember the hormones released by the anterior pituitary, use the mnemonic FLAT PEG: Follicle-stimulating hormone, Luteinizing hormone, Adrenocorticotropic hormone, Thyroid-stimulating hormone, Prolactin, Endorphins, and Growth hormone. Both ADH and oxytocin are released by the posterior pituitary.
Example Question #52 : Endocrine System
Which of the following answer choices contains only hormones secreted by the anterior pituitary gland?
TSH and Estrogen
ADH and ACTH
Oxytocin and ADH
LH and Oxytocin
FSH and ACTH
FSH and ACTH
The correct answer choice is the one containing FSH and ACTH. FSH, or Follicle-stimulating hormone, and ACTH, or Adrenocorticotropic hormone, are each secreted by the anterior pituitary gland. The anterior pituitary hormones can be remembered by the mnemonic, FLATPEG (FSH, LH, ACTH, TSH, Prolactin, Endorphins, Growth Hormone).
Each of the other answer choices contains no more than one anterior pituitary hormone, along with either Estrogen (secreted by the ovaries), Oxytocin (secreted by the posterior pituitary), or ADH/Vasopressin (secereted by the posterior pituitary).
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