Biology 109 Unit 4 Exam Questions and
Answers 100% Pass
Which one of the following is not an advantage of chemical messengers over electrical
signals? - ✔✔chemical molecules initiate faster responses
In this type of signaling, secreted molecules diffuses locally and trigger a response in
the cells that secrete them. - ✔✔autocrine
Synthesized in the hypothalamus, these hormones travel along the extended axons of
neurosecretory cells to the posterior pituitary. - ✔✔ADH and oxytocin
A form of asexual reproduction in which the egg develops without being fertilized. -
✔✔parthenogenesis
Conveys the egg that is released by the ovary to uterus - ✔✔oviduct
The thick, yellowish and alkaline fluid produced by these accessory glands constitutes
approximately 60% of the volume of semen. - ✔✔seminal vesicles
The hypothalamic hormone that stimulates hormone secretion by the anterior pituitary
gland - ✔✔GnRH
The movement of the membrane potential from a value of -70 mV to a value of -80mV
would be termed a(n) - ✔✔hyperpolarization
The reason that the resting membrane potential of a neuron is closer to Ek than to Ena is
that the membrane has - ✔✔more open K+ channels than Na+ channels
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 1
,Threshold stimuli are those which are strong enough to - ✔✔cause a net influx of
positively charged Na+ ions from outside to inside the cell
In a simple synapse, neurotransmitter chemicals are released by the - ✔✔presynaptic
membrane
myelinate axons in the CNS - ✔✔oligodendrocytes
produce the myelin sheaths that surround axons in the PNS - ✔✔Schwann cells
immune cells in the CNS that protect against pathogens - ✔✔microglia
participate in formation of the blood-brain barrier - ✔✔astrocytes
The division of the nervous system that have antagonistic or opposing actions are? -
✔✔sympathetic and parasympathetic
Which area of the brain is most intimately associated with the unconscious control of
respiration and circulation? - ✔✔medulla
What do Wernicke's and Broca's regions of the brain affect? - ✔✔speech
If someone said to you that a particular hormone utilizes a G protein-coupled receptor
in its signal transduction pathway, you would know that the hormone - ✔✔has
receptors on the cell surface
The different effect of the hormone epinephrine on the blood vessels of the intestines
and skeletal muscle involve - ✔✔different signal transduction pathways
different receptors for the hormone
Which of the following statements comparing water-soluble and lipid-soluble
hormones is FALSE? - ✔✔only lipid-soluble hormones bind to a receptor protein to
initiate their response
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 2
, Which of the following hormones has a nontropic effect only? - ✔✔prolactin
In the thyroid hormone cascade pathway, thyroid hormone exerts negative feedback on
the - ✔✔hypothalamus
anteriori pituitary
Releasing and inhibiting hormones secreted by nerve cells of the _______ regulate
hormones released by the _____ - ✔✔hypothalamus, anterior pituitary
Metamorphosis in the caterpillar is determined by? - ✔✔low JH levels
A disease that destroys the adrenal cortex should lead to an increase in the plasma
levels of? - ✔✔adrenocorticotropic hormone (ACTH)
Sexual reproduction - ✔✔can produce diverse phenotypes that may enhance survival of
a population in a changing environment
Which of the following statements comparing spermatogenesis and oogenesis is (are)
TRUE? - ✔✔spermatogenesis, including the mitotic divisions of stem cells, occurs
throughout adolescence and adulthood
Human sperm cells first arise in the - ✔✔seminiferous tubules
In the male normal spermatogenesis requires - ✔✔FSH
LH
testosterone
Completion of meiosis II in oogenesis requires - ✔✔penetration of the secondary oocyte
by a sperm
The increase in LH concentration caused by increased estradiol secretion from the
growing follicle is an example of - ✔✔positive feedback
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 3
Answers 100% Pass
Which one of the following is not an advantage of chemical messengers over electrical
signals? - ✔✔chemical molecules initiate faster responses
In this type of signaling, secreted molecules diffuses locally and trigger a response in
the cells that secrete them. - ✔✔autocrine
Synthesized in the hypothalamus, these hormones travel along the extended axons of
neurosecretory cells to the posterior pituitary. - ✔✔ADH and oxytocin
A form of asexual reproduction in which the egg develops without being fertilized. -
✔✔parthenogenesis
Conveys the egg that is released by the ovary to uterus - ✔✔oviduct
The thick, yellowish and alkaline fluid produced by these accessory glands constitutes
approximately 60% of the volume of semen. - ✔✔seminal vesicles
The hypothalamic hormone that stimulates hormone secretion by the anterior pituitary
gland - ✔✔GnRH
The movement of the membrane potential from a value of -70 mV to a value of -80mV
would be termed a(n) - ✔✔hyperpolarization
The reason that the resting membrane potential of a neuron is closer to Ek than to Ena is
that the membrane has - ✔✔more open K+ channels than Na+ channels
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 1
,Threshold stimuli are those which are strong enough to - ✔✔cause a net influx of
positively charged Na+ ions from outside to inside the cell
In a simple synapse, neurotransmitter chemicals are released by the - ✔✔presynaptic
membrane
myelinate axons in the CNS - ✔✔oligodendrocytes
produce the myelin sheaths that surround axons in the PNS - ✔✔Schwann cells
immune cells in the CNS that protect against pathogens - ✔✔microglia
participate in formation of the blood-brain barrier - ✔✔astrocytes
The division of the nervous system that have antagonistic or opposing actions are? -
✔✔sympathetic and parasympathetic
Which area of the brain is most intimately associated with the unconscious control of
respiration and circulation? - ✔✔medulla
What do Wernicke's and Broca's regions of the brain affect? - ✔✔speech
If someone said to you that a particular hormone utilizes a G protein-coupled receptor
in its signal transduction pathway, you would know that the hormone - ✔✔has
receptors on the cell surface
The different effect of the hormone epinephrine on the blood vessels of the intestines
and skeletal muscle involve - ✔✔different signal transduction pathways
different receptors for the hormone
Which of the following statements comparing water-soluble and lipid-soluble
hormones is FALSE? - ✔✔only lipid-soluble hormones bind to a receptor protein to
initiate their response
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 2
, Which of the following hormones has a nontropic effect only? - ✔✔prolactin
In the thyroid hormone cascade pathway, thyroid hormone exerts negative feedback on
the - ✔✔hypothalamus
anteriori pituitary
Releasing and inhibiting hormones secreted by nerve cells of the _______ regulate
hormones released by the _____ - ✔✔hypothalamus, anterior pituitary
Metamorphosis in the caterpillar is determined by? - ✔✔low JH levels
A disease that destroys the adrenal cortex should lead to an increase in the plasma
levels of? - ✔✔adrenocorticotropic hormone (ACTH)
Sexual reproduction - ✔✔can produce diverse phenotypes that may enhance survival of
a population in a changing environment
Which of the following statements comparing spermatogenesis and oogenesis is (are)
TRUE? - ✔✔spermatogenesis, including the mitotic divisions of stem cells, occurs
throughout adolescence and adulthood
Human sperm cells first arise in the - ✔✔seminiferous tubules
In the male normal spermatogenesis requires - ✔✔FSH
LH
testosterone
Completion of meiosis II in oogenesis requires - ✔✔penetration of the secondary oocyte
by a sperm
The increase in LH concentration caused by increased estradiol secretion from the
growing follicle is an example of - ✔✔positive feedback
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 3
