anatomical position

-Body erect - Palms, arms, and hands forward

axis

The imaginary midline around which body pivots

Frontal or Coronal plane

divides the body into front and back halves

What is planes of reference?

different planes of reference is used for identifying structures

Sagittal plane

Any plane that divides the body into right and left portions

Midsagittal plane

Divides the body into right and left halves (vertically through the nose)

Transverse or horizontal plane

divides the body into upper (superior) and lower (inferior) halves

Anterior or ventral

toward the front or belly side of the body

Posterior or dorsal

toward the back or rear

Superior or cranial

toward the head or upper end

Inferior or caudal

toward the tail, or further from the head than some other structure

Medial or mesial

toward the midline or median plane

lateral

away from midline

proximal

toward the point of attachment

distal

away from the point of attachment

adduct

toward the midline

abduct

away from the midline

anterior/cranial

toward the head

posterior/caudal

toward the tail

ventral

front

prone

body horizontal with face down

supine

body horizontal with face up

flexion

bending at a joint

extention

straightening out a joint

ipsilateral

same side

contralateral

opposite side

You can have a healthy peripheral auditory system but if the central system isn't functioning you can't hear anything True or False

true

what is the bridge between the peripheral and central structures?

auditory nerve

is the auditory nerve part of the peripheral or central system

peripheral

when does the ear begin to form?

3 weeks after gestation

when is the ear completed by

before the end of the 3rd trimester

how long does it take for the inner, middle and outer ear to emerge, mature and begin to function as an auditory system?

8 months

what does the risk of congenital malformation depend on?

gestation time

What disorder is associated with congenital deafness

albinism

Since the ear is developed so early in pregnancy some mother don't know their pregnant which leads to...

higher rates of ototoxicity

What parts of the of the body begin to form in utero, in addition what auditory systems begins to develop at 3 weeks?

-Neural tube, heart, and brain - auditory pit and tubotympanic

What parts of the of the body begin to form in utero, in addition what auditory systems begins to develop at 4 weeks?

- limbs - otocysts develops and auditory meatus starts to form

How big is the embryo and what auditory systems begins to develop at 5 weeks?

- 1/3 of an inch - auditory meatus starts to form

What parts of the of the body begin to form in utero, in addition what auditory systems begins to develop at 6 weeks?

- eyes - semicircular canals, external ear hillocks

How big is the embryo and what auditory systems begins to develop at 7 weeks

-Formation of teeth, muscles, genitals -external ear and cochlea

explain the embryologic development starting from a flat disk

Starts as a flat disk; as it develops, it gets an indentation create a line down the embryo that folds in on itself and will create what's called the neural tube and creates our brain and spinal cord.

What happens if something happens during the development of the neural tube?

end up with neural tube defects like spina bifida and neurological conditions

Since the the external and inner ear are forming at the same time it's possible if something goes wrong with one structure the other one might have complications True or false

True

What happens within 25 hours of the embryo being placed

embryonic disc splits leading to the development of ectodermal-lined primitive groove and primitive fold

what happens after the 25 hours the embryo as been placed

primitive groove deepens into a primitive pit that becomes the neural groove and neural fold

Explain the development of the inner ear at 3 weeks

- development of the auditory placode and gut - invagination into the otic pit and migration of otocyst

At 3 weeks the auditory placode is the

Ectroderm

At 3 weeks the gut ectoderm will contribute to what parts of the ear

inner and middle ear

Explain the development of the inner ear at 7 weeks

-Labyrinth's are recognizable - Cochlea has one turn - first sensory cells in utricle

Explain the development of the inner ear at 11 weeks

- CN VIII attaches - Cochlea has 2.5 turns

At the end of week four what is happening to the endolymph

Otocyst assumes a pear shape; outgrowths becomes endolymphatic sacs and its the beginning of the utricle and saccule

what is the relationship of the -auditory placode -Otic pit -otic vesicles AND what structure does it form?

thickening of the side of the embryo that will turn into/migrate to the otic pit because the cell dips down and it will close up and creates the otic vesicles which turns into out inner ear structures

when can a baby in utero react to sounds

by 21 weeks

how do we get endolymph in the entire length of the cochlea

due to sensory cells turning

what is the cochlear duct?

the spiral shape of the cochlea

What division of the auditory systems happens at 5 weeks

division of the auditory and vestibular systems

Explain the development of the inner ear at week 5

the tip of the saccule elongates and begins to coil about itself (2.5) turns forming the cochlear duct

Explain the development of the inner ear at weeks 16-22

Otic capsule ossifies, forming the bony labyrinth (petrous component of the temporal bone)

At what weeks is the inner ear complete, adult size and shaped

20-22 weeks

By 20-22 weeks how long and how heavy is the fetus in utero

8-10" and <1 Ib

Week 16 is important because of what

the bones start to harden and theres connection of the peripheral and central systems

Explain the development of the middle ear at week 3

tubotympanic recess (1st branchial pouch endoderm) approaches 1st cleft ectoderm

Explain the development of the middle ear at week 6

Ossicular mesenchyme separates from cleft and pouch

Explain the development of the middle ear at week 20

tympanic cavity grows to enclose ossicles

Explain the development of the middle ear at week 22

extension to form mastoid antrum

Explain the development of the middle ear at week 33

early mastoid pneumatization

what turns into the ossicles

mesoderm

what is the tubotympanic recess

a little pouch that comes inward from the opposite direction and turns into our middle ear space. It will enclose the ossicles.

What is apart of the 1st branchial arch; ossicles

-Meckel's cartilage: head of malleus, body and short process of incus -tensor tympani muscles -trigeminal nerve: mandibular branch supplies tensor tympani muscle -1st arch artery- involutes

What is apart of the 2nd branchial arch; ossicles

- reichert's cartilage: long process of incus, handle of malleus, stapes superstructure and tympanic surface of footplate -Stapedius muscle -facial nerce: stapedial nerce -2nd arch artery- stapedial artery- involutes

At what weeks do the malleus and incus are separate bones connected at a joint and move the way their supposed to

32 weeks

External ear: Hillocks merge as the...

pinna forms

External ear: first pharyngeal modifies as the...

external auditory meatus

External ear: shifts in position from pharyngeal region to the...

side of the head as mandible develop and teeth form

How big is the embryo and what auditory systems begins to develop at 8 weeks

-1 inch:becomes fetus -middle ear ossicles & tympanic membrane begin to form