Exam 2 Flashcards
Which of the following body parts are not highly represented on the sensory homunculus?
eyes
The brain recognizes action potentials from different sensory modalities as separate and distinct because:
action potentials from different sensory modalities are carried on different nerve tracts.
The generator potential produced by a Pacinian corpuscle in response to mechanical stimulation is:
proportional to stimulus intensity.
While walking barefoot on gravel, which receptor allows you to feel the texture of the gravel pressing into your feet?
Pacinian corpuscles
Which statement about the receptive field of a sensory neuron on skin is true?
Receptive fields of sensory neurons have a characteristic shape with excitatory and inhibitory regions.
Which of the following is involved in pain pathways in the spinal cord?
Substance P
Afferent fibers from the periphery that carry nociceptive information terminate on neurons in the:
dorsal horn cells of the spinal cord.
Muscles are connected to bone by
tendons
Severing sensory fibers from a monkey’s arm will cause the monkey to stop using that arm, but it will begin to use it again if the other (good) arm is restrained. This demonstrates that:
proprioceptive information can be supplemented with feedback from other senses.
Eddie just learned that the medication he has been taking has no known pharmaceutical effects, but has still been alleviating his symptoms. This medications effects are best known as:
A placebo
In vertebrates, _______ is primarily responsible for fine-tuning refraction.
ears
The _______ muscles are essential for accommodation
ciliary
Which of the following is incorrectly paired?
horizontal cells; action potentials
Which of the following accurately describes the route for the passage of visual information?
Optic nerve, optic tract, occipital cortex
Which of the following statements is true?
The right visual field projects to the eyes and then to the left cerebral hemisphere.
The ______ of the retina has the sharpest visual acuity because it is most densely concentrated with ________.
Fovea; cones
Which of the following statements about rod receptors is false?
Rods contain a special photopigment called opsin.
Which of the following can be corrected with glasses?
Hyperopia
Which type of color deficiency is most common?
Red-green
Because dogs only have two different types of cones:
They are color-deficient and see a reduced range of colors compared to humans
Glands that secrete their products outside the body are referred to as _______ glands.
exocrine
Considering the organizational effect, which of the following would display lordosis?
An adult male rat who was castrated at birth and given estrogen before exposure to another male
The external genitalia of an XY individual can have a feminine form at birth as a result of:
insensitivity to androgens.
People with Turner’s syndrome have:
Only one X chromosome.
Which of the following are two of the three major classes of hormones?
Peptide and steroid
The traditional understanding of steroid hormones is that they exert their effects by:
entering cells and altering gene expression.
Cells located in the _______ synthesize oxytocin and vasopressin and transport these hormones to the _______.
hypothalamus; posterior pituitary
Compared to neurotransmitters, hormone effects are generally:
more widespread in the body.
The essential feature of tropic hormones is that they:
affect the secretion of other endocrine glands.
Which of the following has been associated with oxytocin?
All of the above:
- love/affection
- autism spectrum disorder
- Ethnocentrism
- Uterine contractions
Hertz (Hz) is the unit used to measure _______ of sound waves, which is perceived as ________.
Frequency; pitch
Which of the following is not one the types of neural connections with hair cells?
OHC afferents, which convey messages from the hair cells to the brain; conveying information to the brain about the perception of sounds coming specifically from the basilar membrane
Prolonged exposure to loud noises is most likely to result in:
Sensorineural deafness
Compared to the low pitch of a tuba, the high pitch of a flute is likely to:
Activate the base of the basilar membrane more
Which of the following structures is not part of the external or middle ear?
Organ of Corti
The stereocilia of the hair cells contact the:
tectorial membrane.
Which of the following is not a type of taste papillae?
Turbinate
All of these are considered basic tastes except
Spicy
A person diagnosed with anosmia:
cannot experience flavor.
New olfactory receptor cells are formed from:
basal cells.
As light levels increase we switch from using the _____ system to the ______ system
scotopic (rods), photopic (cones)
The left temporal hemiretina takes in the ______ side info
left (same
The left nasal hemiretina takes in the _______ side info
right
Everything gets segregated in the _____ so the left visual field eventually goes to the ________ primary visual cortex
optic chiasm, right
Crossing over of the info for the visual system happens at the ____
optic chiasm
lateral geniculate nucleus
thalamic nucleus that receives incoming visual information and then sends it to the primary visual cortex
medial geniculate nucleus
the part of the thalamus that relays auditory signals to the temporal cortex and receives input from the auditory cortex
The primary visual cortex is in the ______
occipital lobe
dorsal stream
visual path in the parietal cortex that helps the motor system locate objects; the “where” path (goes to posterior parietal)
ventral system
what system (goes to inferotemporal)
accomodation of lens
lenses change shape to focus on objects near or far (near becomes cylindrical; far flattens)
amacrine cells
Specialized retinal cells that contact both the bipolar cells and the ganglion cells,
horizontal cells
Specialized retinal cells that contact both the receptor cells and the bipolar cells
blind spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there
Cones
retinal receptor cells that are concentrated in the Fovea and that function in daylight or in well-lit conditions. The cones are for acuity and color (photopic vision)
photopic vision
the ability to perceive visual stimuli under bright light conditions due to the activity of cones
Rods
Specialized visual receptors that play a key role in night vision and peripheral vision.
ciliary muscle
muscle that helps focus light on the retina by controlling the curvature of the lens of the eye
convergence
The level of convergence is the level of how much info is lost along the way
High convergence would mean there was a lot of info at the start but it gets condensed
cones have ___ convergence
low; leads to low sensitivity, but high accuracy
rods have _____ convergence
high; leads to high sensivity, but low accuracy
Receptor Cell
Detects specific forms of energy (stimuli) and sends action potentials (APs) to the brain.
Sensory Transduction
Conversion of environmental stimuli into APs that the brain understands.
Labeled Lines
Separate nerve tracts for different senses, e.g., touch vs. pain pathways.
Pacinian Corpuscle
Detects vibration and pressure by mechanically opening sodium channels.
Touch Pathway (Dorsal Column System)
From skin → spinal cord → medulla (synapse) → thalamus → primary somatosensory cortex.
Pain Pathway (Anterolateral Tract)
Pain receptors → spinal cord → brainstem → thalamus → cingulate cortex.
Nociceptors
Detect pain and use neurotransmitters like glutamate and Substance P.
Endogenous Opiate System
Modulates pain through pathways involving the periaqueductal gray (PAG).
Primary Motor Cortex
Located in the precentral gyrus, controlling voluntary movement.
Pyramidal System
Pathway: Cortex → spinal cord → motor neurons → muscles.
Motor Neuron
Transmits APs to muscles at the neuromuscular junction using acetylcholine (ACh).
Stretch Reflex
Muscle spindle detects stretch and triggers reflexive muscle contraction.
Sound Transduction
Soundwaves enter ear canal → tympanic membrane vibrates → ossicles amplify → cochlea.
Auditory Pathway
Cochlea → cochlear nucleus → superior olivary nucleus → inferior colliculus → medial geniculate nucleus → auditory cortex.
