Biology 331 Final Exam with correct
answers 100% 2026
Neuron - Correct Answera specialized cell transmitting nerve impulses; a nerve cell.
Fixed action pathway - Correct AnswerSENSORY INPUT → STIMULUS THRESHOLD → SIGNAL TO
INNATE RELEASING MECHANISM → FIXED ACTION PATTERN
Neural network - Correct Answerrefers to interconnected neuron cells
Robert Sapolsky's work - Correct Answer
Hormones involved in insect metamorphosis - Correct Answer
Altruism - Correct Answerto benefit another at a cost to one's own fitness
Reciprocal altruism - Correct Answerbehaviour whereby an organism acts in a manner that
temporarily reduces its fitness while increasing another organism's fitness, with the expectation
that the other organism will act in a similar manner at a later time
Cooperative breeding - Correct Answerin humans and certain other species, a system involving
networks of support in which individuals other than parents contribute resources toward
rearing the young
Prolactin - Correct Answera protein best known for its role in enabling mammals (and birds),
usually females, to produce milk
castration (and effects of) - Correct Answer
,Insect and chordate eyes - Correct AnswerSchematic illustration of the compound eye of an
insect. A: surface of compound eye, showing the facet lenses. B: longitudinal cross section of an
ommatidium. C: structure of one of the photoreceptor cells within an ommatidium, showing the
microvilli, containing the photopigment, that contribute to the structure of the rhabdom.
Main parts of honey bee brain - Correct AnswerAn insect brain is comprised of a
protocerebrum, a deutocerebrum, and a tritocerebrum. In honeybees, the tritocerebrum is
contiguous and fused to the back of the protocerebrum and the deutocerebrum; therefore, the
boundary becomes ambiguous. In addition, the suboesophageal ganglion is fused to the brain;
thus, the ventral nerve cord between them has been lost. The following outlines the structure
and function of the nerve plexuses in the honeybee's brain.
Mushroom body (MB): A pair of mushroom-shaped nerve plexuses are located, one on each
side of the protocerebrum. Each mushroom body is comprised of a calyx, a peduncle, and an α
and β lobe; the calyx has separate input regions for visual, olfactory, and mechanical sensing.
Endogenous neurons of mushroom body (Kenyon cells) form a layered structure, and individual
layers are considered to process specific types of sensory information. Within the output
regions of the mushroom body (α and β lobes), there are branching mushroom body exogenous
neurons, which have been shown to change their mode of response upon learning.
Optic lobe (OL): A pair of optic lobes are located, one on each side of the protocerebrum. They
extend inside the compound eyes. An optic lobe comprises of three nerve plexus regions
(lamina, medulla, and lobula), and the respective regions conduct three-step information
processing on color/shape identification and movement vision. The lamina is involved in
detection of light/dark contrast (determination of the contour of an object), the medulla is
involved in the signaling of spatial and color vision information, and the lobula is involved in
motion detection.
Central body (CB): This is an unpaired nerve plexus in the center of the protocerebrum. It is
considered to be pivotal in movement, but its full function remains unknown. In grasshoppers,
the cent
Nervous system of chordates (general structure) - Correct AnswerMajor reorganization (dorsal
nerve cord vs. ventral nerve cord in arthropods)
FOXD gene duplications resulted in more complex brain development (Amphioxus -lancelets,
have ancestral chordate morphology)
, Parts of a neuron - Correct Answercell body, dendrites, axon
Neurotransmitters - Correct Answerchemical messengers that cross the synaptic gaps between
neurons
Hormones - Correct Answerchemical messengers that are manufactured by the endocrine
glands, travel through the bloodstream, and affect other tissues
Androgens vs estrogens - Correct Answer
Melatonin function - Correct Answermaintains sleep/wake cycle; high during sleep
Short day/Long day breeders - Correct Answer
Dominance hierarchy - Correct Answerrankings that represent the relative social power of
those in a group
Kin selection - Correct Answeris a form of selection in which inclusive fitness increases as a
result of increasing INDIRECT fitness
Inclusive fitness - Correct AnswerDIRECT FITNESS + INDIRECT FITNESS= 0.5 + 0.75 = 1.25
Direct fitness - Correct Answerincrease to fitness from your own offspring. → 0.5 X 1 = 0.5
Coefficient of relatedness (r) - Correct Answeris the measure of relatedness between two
individuals
answers 100% 2026
Neuron - Correct Answera specialized cell transmitting nerve impulses; a nerve cell.
Fixed action pathway - Correct AnswerSENSORY INPUT → STIMULUS THRESHOLD → SIGNAL TO
INNATE RELEASING MECHANISM → FIXED ACTION PATTERN
Neural network - Correct Answerrefers to interconnected neuron cells
Robert Sapolsky's work - Correct Answer
Hormones involved in insect metamorphosis - Correct Answer
Altruism - Correct Answerto benefit another at a cost to one's own fitness
Reciprocal altruism - Correct Answerbehaviour whereby an organism acts in a manner that
temporarily reduces its fitness while increasing another organism's fitness, with the expectation
that the other organism will act in a similar manner at a later time
Cooperative breeding - Correct Answerin humans and certain other species, a system involving
networks of support in which individuals other than parents contribute resources toward
rearing the young
Prolactin - Correct Answera protein best known for its role in enabling mammals (and birds),
usually females, to produce milk
castration (and effects of) - Correct Answer
,Insect and chordate eyes - Correct AnswerSchematic illustration of the compound eye of an
insect. A: surface of compound eye, showing the facet lenses. B: longitudinal cross section of an
ommatidium. C: structure of one of the photoreceptor cells within an ommatidium, showing the
microvilli, containing the photopigment, that contribute to the structure of the rhabdom.
Main parts of honey bee brain - Correct AnswerAn insect brain is comprised of a
protocerebrum, a deutocerebrum, and a tritocerebrum. In honeybees, the tritocerebrum is
contiguous and fused to the back of the protocerebrum and the deutocerebrum; therefore, the
boundary becomes ambiguous. In addition, the suboesophageal ganglion is fused to the brain;
thus, the ventral nerve cord between them has been lost. The following outlines the structure
and function of the nerve plexuses in the honeybee's brain.
Mushroom body (MB): A pair of mushroom-shaped nerve plexuses are located, one on each
side of the protocerebrum. Each mushroom body is comprised of a calyx, a peduncle, and an α
and β lobe; the calyx has separate input regions for visual, olfactory, and mechanical sensing.
Endogenous neurons of mushroom body (Kenyon cells) form a layered structure, and individual
layers are considered to process specific types of sensory information. Within the output
regions of the mushroom body (α and β lobes), there are branching mushroom body exogenous
neurons, which have been shown to change their mode of response upon learning.
Optic lobe (OL): A pair of optic lobes are located, one on each side of the protocerebrum. They
extend inside the compound eyes. An optic lobe comprises of three nerve plexus regions
(lamina, medulla, and lobula), and the respective regions conduct three-step information
processing on color/shape identification and movement vision. The lamina is involved in
detection of light/dark contrast (determination of the contour of an object), the medulla is
involved in the signaling of spatial and color vision information, and the lobula is involved in
motion detection.
Central body (CB): This is an unpaired nerve plexus in the center of the protocerebrum. It is
considered to be pivotal in movement, but its full function remains unknown. In grasshoppers,
the cent
Nervous system of chordates (general structure) - Correct AnswerMajor reorganization (dorsal
nerve cord vs. ventral nerve cord in arthropods)
FOXD gene duplications resulted in more complex brain development (Amphioxus -lancelets,
have ancestral chordate morphology)
, Parts of a neuron - Correct Answercell body, dendrites, axon
Neurotransmitters - Correct Answerchemical messengers that cross the synaptic gaps between
neurons
Hormones - Correct Answerchemical messengers that are manufactured by the endocrine
glands, travel through the bloodstream, and affect other tissues
Androgens vs estrogens - Correct Answer
Melatonin function - Correct Answermaintains sleep/wake cycle; high during sleep
Short day/Long day breeders - Correct Answer
Dominance hierarchy - Correct Answerrankings that represent the relative social power of
those in a group
Kin selection - Correct Answeris a form of selection in which inclusive fitness increases as a
result of increasing INDIRECT fitness
Inclusive fitness - Correct AnswerDIRECT FITNESS + INDIRECT FITNESS= 0.5 + 0.75 = 1.25
Direct fitness - Correct Answerincrease to fitness from your own offspring. → 0.5 X 1 = 0.5
Coefficient of relatedness (r) - Correct Answeris the measure of relatedness between two
individuals
