Lab 3 Flashcards
fill in the blank
label the cranial nerves
how important is the sense of smell to the sense of taste?
The sense of smell is closely linked to the sense of taste, as the olfactory nerve (Cranial Nerve I) detects odors that significantly enhance flavor perception. Without the olfactory input, the facial (VII), glossopharyngeal (IX), and vagus (X) nerves, which transmit taste signals, provide only basic sensations like sweet, salty, sour, bitter, and umami, making flavors less complex and enjoyable.
where are visual signals initiated
retina
what do drops that dilate the pupil do?
they allow more of the retina and vitreous humor to be viewed
what is presbyopia
Presbyopia is an age-related condition in which the eye gradually loses its ability to focus on nearby objects. It occurs due to the hardening and loss of elasticity of the lens, making it difficult for the eye to adjust its focus for close-up vision, a process called accommodation.
what are the four muscles controlling eye movement innervated by the oculomotor nerve
inferior rectus, medial rectus, superior rectus and levator palpebrae
what causes constriction of the pupil
papillary sphincter
what controls the lens thickness and distance accommodation
ciliary muscles
what is astigmatism
refers to a mismatch in the curvature of the surface of the cornea and/or lens
what are the visual cells for the perception of colour
cones
what are the 3 colors that cones observe
red, green, and blue
identify the 2nd, 3rd and 4th cranial nerves
what does failing the H test mean
dysfunction of the extrinsic eye muscles or the trochlear nerve
list the 3 rootlets of the trigeminal nerve
ophthalmic (eye and above)
maxillary (upper jaw)
mandibular (lower jaw)
differentiate the eye movements controlled by the trochlear nerve and the abducens nerve
trochlear: movement of eye inferiorly and laterally
abducens: abduction of the lateral rectus
what happens if there is damage to the vestibulocochlear nerve
sensorineural hearing loss
glossopharyngeal nerve function
innervates the pharyngeal muscles, salivary glands and conducts signals from the pressure receptors in the carotid artery. also provides sensory innervation for taste -in the rear third of the tongue
vagus nerve function
parasympathetic innervation of the heart and smooth muscles of the abdominal organs. also provides sensory innervation for the auditory canal linking nausea to water dripped into the ear.
accessory nerve function
innervates the sternocleidomastoid muscle and the trapezoid muscle
hypoglossal nerve
innervates muscles of the tongue
during a dissection of a cows eyes, u notice that the cornea is cloudy. why
The cornea appears cloudy in a dissected cow’s eye because it has lost its transparency due to the lack of hydration and blood supply after death. In living animals, the cornea remains clear through a precise balance of hydration, maintained by the aqueous humor and active ion pumps, which cease functioning after death, leading to cloudiness.
once the incision in the cows eye has been made, what fluid leaks out and what is its function
fill in the blanks
what is the gelatinous component found in the eye
vitreous humor
what is the eye component that helps with night vision in animals
tapetum lucidum
what is the purpose of the tapetum lucidum?
The tapetum lucidum is a reflective layer found in the eyes of many animals, including cows, located behind the retina. Its purpose is to enhance vision in low-light conditions by reflecting light back through the retina, giving the photoreceptor cells a second chance to detect the light. This is why animals with a tapetum lucidum often have eyes that “glow” in the dark.
why is the optic disk referred to as the blind spot
The optic disk is referred to as the blind spot because it is the area on the retina where the optic nerve exits the eye and lacks photoreceptor cells (rods and cones). As a result, it cannot detect light, creating a small gap in the visual field.
what are the 5 components of a reflex
differentiate somatic and autonomic reflexes
what is the difference between these two types of reflex arcs
what is a myotic reflex
