Exam 5 Exam Guide Flashcards
(267 cards)
1
Q
‘indifferent’ embryo refers to
A
stage in embryonic development (typically around weeks 4–7 in humans) when the reproductive structures are not yet differentiated into male or female forms.
2
Q
(Müllerian) ducts
A
potential to become female internal structures:
3
Q
can develop into either testes or ovaries.
A
gonadal ridge
4
Q
The gonads of both males and females begin to develop dur-
ing week
A
5
4
Q
the future male ducts,
A
wolffian ducts
5
Q
where do both ducts empty to
A
cloaca
6
Q
what will the cloaca make
A
bladder and urethra
7
Q
what determines gonad fate
A
presence of Y chromosome
8
Q
if testosterone is present, what happens
A
triggers male sexual differentiation
9
Q
if testosterone is not present, what happens
A
triggers female sexual differntiation
10
Q
ondition in males where the urethral opening (where urine exits the body) is not at the tip of the penis, but instead is located somewhere along the underside
A
hypospadias
11
Q
what causes hypospadias
A
incomplete fusion of the urogenital folds during development
12
Q
what can fix hyposadiass
A
treated with surgery
13
Q
embryonic structure present in all embryos, precursors to external genitalia
A
genital tubercle
14
Q
part of what makes the embryo “indifferent” before sexual differentiation begins.
A
genital tubercle
15
Q
genital tubercle becomes what in males vs females
A
males - glans and shaft of penis
females - clitois
16
Q
Produce sperm and testosterone
A
testes
17
Q
where are testes located
A
in scrotum
18
Q
Stores and matures sperm after they are produced in the testes.
A
epididymus
19
Q
Transports mature sperm from the epididymis to the ejaculatory duct.
A
ductus deferens
20
Q
Formed by the joining of the ductus deferens and seminal vesicle duct; delivers sperm and seminal fluid to the prostatic urethra.
A
ejaculatory duct
21
Q
primary structures of sperm production and transport
A
testes, epididymus, ductus deferens, ejaculatory duct, urethra
22
Q
Produces ~60% of semen volume: fructose-rich fluid that nourishes sperm and enhances motility.
A
seminal galnd
23
Q
Secretes a slightly alkaline fluid (~30% of semen) that helps activate sperm and neutralize vaginal acidity.
A
prostate gland
24
Secrete pre-ejaculate: a clear mucus that lubricates and neutralizes urine traces in the urethra.
bulbourethral gland
25
Holds and protects the testes outside the body, keeping them at a temperature ideal for sperm production
scrotum
26
spermatic cord contains what
ductus deferens, blood vessels, nerves, and lymphatics
27
A passage in the abdominal wall that the spermatic cord passes through; site of possible hernias.
inguinal canal
28
Raises and lowers the testes to regulate temperature for optimal sperm production.
cremaster muscle
29
A fetal structure that guides the descent of the testes from the abdomen into the scrotum before birth.
gubernaculum
30
A network of veins that cools arterial blood before it reaches the testes, helping maintain proper testicular temperature.
pampiniform plexus
31
Two cylindrical erectile tissues on the dorsal side of the penis that fill with blood to create an erection.
corpora cavernosa
32
A single column of erectile tissue surrounding the urethra, keeps the urethra open during erection and forms the glans penis.
corpus spongiosum
33
testes initially form where
high in the abdomen
34
attaches the testes to the future scrotum and guides their movement downward.
gubernaculum
35
As the fetus grows, abdominal pressure and hormonal signals (especially testosterone) push the testes through the:
inguinal canal
36
Testes complete descent into the scrotum, ideally when
before birth
37
undescended testis/testes called what
cryptorchidism
38
Why are males more susceptible to inguinal hernias?
because of how testes descend during development creating a natural weakness, also a larger inguinal canal, higher abdominal pressure exposure
39
site of spermatogenesis
seminiferous tubules
40
production of sperm is called what
spermatogenesis
41
sperm created directly along what
walls of seminiferous tubules
42
Where are
sperm stored and what is the pathway of their exit?
sperm stored in epididymis
starts in seminiferous tubules -> epididymus -> ductus deferens -> ejaculatory duct -> urethra
43
basic roles of Parasympathetic NS in arousal
responsible for increased blood flow in erectile tissues, increases blood flow into corpora caverns and corpus spongiosum
44
basic roles of SNS in sex
triggers ejaculation , causes smooth muscle contraction to deliver sperm to the urethra and forces it out
45
How do corpora cavernosa, corpus spongiosum contribute to arousal?
corpora cavernosa - 2 cylindrical columns of erectile tissue, fill with blood to cause erection
corpus spongiosum - single column erectile tissue that surround urethra, stays softer to protect urethra
46
What do the
smooth muscles do along the sperm “pathway”?
responsible for peristalsis, pushes sperm through pathway, involuntary control
47
When do the prostate and seminal glands
release their secretions?
during process of emission
48
What gland contributes most to seminal fluid?
seminal glands
49
what do seminal gland contribute
fructose, prstaglandins, substances that suppress immune response of females against semen, clotting enzymes
50
what does prostate gland contribute to
milky fluid that enhance sperm motility, clotting enzymes,
51
what do bulbourethral glands contribute
mucus for lubrication and also for neutralizing urethra
52
What structure is cut during vasectomy?
ductus deferens
53
What
happens when a man has a swollen prostate (prostatic hyperplasia) what symptoms would they
have and why does a swollen prostate cause them?
- frequent urination, urgency to urinate, weak urine streak, difficulty starting urination, incomplete emptying of bladder
- swollen prostate causes this bc of obstruction of urinary flow and bladder strain
54
female gonads that produce eggs (ova) and secrete hormones like estrogen and progesterone.
ovary
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release of an egg each month
ovulation
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funnel-shaped opening of the fallopian tube (oviduct) near the ovary.
ostium
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ostiums finger like projections called what
fimbraie
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a tube that connects the ovary to the uterus
oviduct
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provide the site of fertilization
oviduct
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fter ovulation, the egg travels through the... wehre what can happen
through oviduct, may be fertilized by sperm
61
hollow, muscular organ where implantation of a fertilized egg occurs and pregnancy develops
uterus
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lower part of the uterus that connects to the vagina
cervix
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barrier to protect the uterus from infections and also allows the passage of menstrual blood and sperm.
cervix
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connects the uterus to the vagina
cervical canal
65
cervical canal makes what for what
mucus to either facilitate or prevent sperm from entering uterus
66
muscular canal that serves as the passageway for menstrual blood to leave the body and for sperm to enter during sexual intercourse.
vagina
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nnermost layer of the uterus
endometrium
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thickens each month in response to hormonal signals in preparation for implantation of a fertilized egg
endometrium
69
If implantation does not occur, what happens
endometrium is shed during menstruation
70
ontains blood vessels and glands to support early pregnancy.
endometrium
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middle layer of the uterine wall, consisting of smooth muscle
myometrium
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primary function is to contract during labor to help expel the fetus.
myometrium
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why does myometrium contract during menstruation
help shed endometrial lining
74
Know
epithelium of vagina, oviduct.
vagina - stratified squamous
oviduct - simple columnar with cilia, some secretions that nourish oocyte
75
each ovulated
oocyte is released into the
peritoneal cavity
76
how does oviduct capture egg
performs complex series of movements to capture it
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In females, the Müllerian ducts give rise to:
Uterine (fallopian) tubes
Uterus
Cervix
Upper part of the vagina
78
what develops separate from mullein duct
ovaries
79
ovarian cycle phases
follicular phase, luteal phase
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uterine cycle also known as what
menstrual cycle
81
The uterine cycle describes changes in the...
endometrial lining
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phases of uterine cycle
menstrual phase, proliferative phase, secretory phase
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which phase begins with menstruation
follicular phase
84
Follicles in the ovary grow and mature under the influence of...
FSH
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what ends the follicular phase
LH surge
86
After ovulation, the ruptured follicle becomes the
corpus luteum
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The corpus luteum secretes what to maintain uterine lining
progesterone and some estrogen
88
If no fertilization occurs, what happens
corpus luteum goes to corpus albicas, hormone levels fall and menstruation begins
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Shedding of the endometrial lining due to drop in hormones. what phase
menstrual cphase
90
under influence of what, endometrium rebuilds and thickens
estrogen
91
After ovulation, progesterone from the corpus luteum makes the endometrium...
thicker, more vascular, more glandular to support potential embryo
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what happens in follicular phase
follicles in ovary grow and mature
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what happens in luteal phase
ruptured follicle becomes corpus luteum, uterine lining maintained by progesterone secretion,
94
what happens in proliferative phase
endometrium rebuilds and thickens, prepares for possible implantation
95
what happens in secretory phase
progesterone makes endometrium thicker and more vascular,
96
how does estrogen change over follicular phase
starts low, rises steadily as follicles grow, peaks just before ovulation which triggers LH surge
97
how does progesterone change during follicular phase
stays low
98
how does estrogen change during luteal phase
drops slightly after ovulation then rises
99
how does progesterone change during luteal pace
rises sharply after ovulation, peaks in middle of this phase, if no pregnancy it drops
100
Estrogen (E) and Progesterone (P) Together do what
suppress ovulation, inhibit release of FSH and LH
101
Without FSH and LH, what happens
no new follicles stimulated to grow, no LH surge
102
birth control pills contain
synthetic estrogen and progesterone
103
permanent layer of endometrium
basal layer
104
endometrium contains what to regenerate
stem cells
105
Does not shed during menstruation.
basal layer
106
Temporary layer that grows and is shed during the menstrual cycle.
functional layer
107
how does functional layer respond to estrogen
proliferates during proliferative phase
108
progesterone effect on fucntinla layer
makes it secretory, rich in glands and blood vessels to prepare for possible implantation
109
difference between spiral arteries and uterine glands
Spiral arteries: Blood vessels that supply the functional layer of the endometrium; they coil and grow during the cycle and break down if no pregnancy occurs, triggering menstruation.
Uterine glands: Glands in the endometrium that regrow and thicken during the cycle; they secrete nutrients during the secretory phase to support a possible embryo.
110
spiral arteries in proliferative phase
begin growing, are straight
111
spiral arteries in secretory phase
fully developed, coiled
112
uterine glands during proliferative phase
regrow, straight and narrow
113
uterine glands during secretory phase
become coiled and start secreting
114
what do uterine glands release
nutrients during the secretory phase to support a possible embryo.
115
cervix during pregnancy
closed and firm, forms thick mucus plug that prevents bacteria and sperm from entering uterus
116
cervical mucus during follicular phase
thin watery to help sperm travel easily through cervix
117
cervical mucus during ovulation
most fertile, allows and supports sperm
118
cervical mucus during literal phase
blocks sperm and pathogens from entering
119
How does an ovum enter the oviduct?
released from mature follicle, fimbrae of osmium sweep over ovary to capture released ovum, transported into oviduct via cilia
120
How do birth control pills prevent pregnancy
inhibition of ovulation, thickening of cervical mucus, makes endometrium thinner and less receptive to fertilized egg
121
what is endometriosis
fragments of endometrial tissue
are present in the uterine tubes, on the ovary, and in the
peritoneum of the pelvic cavity. extreme pain associated with menstruation, blood accumulates in pelvic cavity
122
what do vestibular glands do
secrete mucus that lubricates the vagina during arousal
123
what is an ectopic pregnancy
pregnancy where fertilized egg implants outside the uterus, dangerous bc it can rupture oviduct, required medical intervention as pregnancy cannot be sustained.
124
what issue can be traced to the disconnection
between ovary and oviduct (i.e. ovary must ‘catch’ the ovum)?
ectopic pregnancy
125
What tissues form mammary
glands and what is found in mammary gland secretion?
- tissues are epithelial, connective, smooth muscle
- milk contains water, protein, carbs, fats, vitamins, minerals
126
What contributes to vaginal lubrication?
(note it is not vaginal epithelium and several sources)
cervical glands, vestibular glands
127
where does fertilization typically occur
right at the beginning of the oviduct
128
What is the function of chorionic gonadotropin?
maintain corpus luteum, stimulate progesterone production, support early pregnancy
129
What releases CG?
primarily released by trophoblast cells , some placenta later on
130
What are the extra-embryonic layers and what do they do?
structures that develop outside embryo, forms layer between trophoblast and embryo, contributes to dev of blood vessels that will later for umbilical cord
131
extra embryonic layers include what
chorion, amnion, yolk sac, allantois
132
what extra embryonic layer contributes to placenta
chorion
133
Where do E and P come from to maintain the placenta early in pregnancy
corpus luteum
134
where do e and p come from to maintain placenta after 3 months pregnancy
placenta
135
what happens during implantation
hatching of blastocyst, attachment to endometrium, invasion of endometrium, formation of placenta, secretion of hCG
136
Role of Trophoblast and Chorion in Implantation:
Trophoblast: The trophoblast is responsible for the initial contact and invasion into the endometrial lining. It secretes enzymes that help break down the uterine tissue to allow the embryo to implant, and it produces hCG to maintain the pregnancy.
Chorion: The chorion forms from the trophoblast and is essential for the development of the placenta. It forms chorionic villi that extend into the endometrium, establishing a maternal-fetal blood exchange system. The chorion also contributes to the outer fetal membrane of the placenta.
137
What is there in
the functional layer to help support an implanted embryo before the umbilical cord forms?
rich blood supply, uterine glands which provide nutrients,
138
What
causes maternal blood to pool along endometrium?
invasion of outer layer of trophoblast, breakdown of maternal blood vessels
139
What is amniotic band syndrome?
strands of the amniotic membrane (the sac that surrounds the fetus) become entangled around parts of the developing fetus. These strands, known as amniotic bands, can wrap around limbs, fingers, toes, or other parts of the body, leading to a range of birth defects or abnormalities.
140
what is placental previa
placenta is abnormally positioned in the uterus covering the os, risks massive bleeding if normal childbirth occurs
141
what is placental abruption
placenta separates prematurely from the uterine wall before the baby is born. This separation can lead to significant bleeding and deprive the baby of oxygen and nutrients. caused by trauma or injury, high bp
142
What is ectopic pregnancy?
ertilized egg implants and begins to develop outside the main cavity of the uterus, typically in one of the fallopian tubes. This type of pregnancy is not viable, meaning the fertilized egg cannot develop properly, and it poses serious health risks to the mother.
143
What happens during pelvic
inflammatory disease?
bacteria enter reproductive organs, usually through hcervix, spread to uterus, oviduct, ovaries
144
Contains the nucleus and organelles.
Integrates incoming signals from dendrites
cell body
145
Branchlike extensions from the cell body.
Receive electrical signals (input) from other neurons.
dentrite
146
A long projection that carries electrical impulses (action potentials) away from the cell body.
axon
147
Located at the end of the axon.
Release neurotransmitters to send signals to the next cell.
axon terminals
148
The junction between the axon terminal of one neuron and the dendrite (or cell body) of another.
synapse
149
neurons communicate using what within a neuron and what between neurons
within - electrical signals
between - chemical signals
150
branches of efferent
somatic and automatic
151
branches of autonomic
sympathetic and parasympathetic
152
what stimulates fight or flight
sympathetic
153
what stimulates rest and digest
parasympathetic
154
What happens to the hollow part of the nerve cord during development?
gives rise to spinal cord and ventricles of brain
155
where are lateral ventricles located
one in each cerebral hemisphere
156
where is third ventricle located
in the dienecphalon
157
where Is fourth ventricle located
in the brainstem
158
function of CSF
cushioning and protection, gives brain buoyancy, circulates nutrients to CNS
159
what produces CSF and where
chorioid plexus tissue produces CSF, it is found within all 4 ventricles of the brain
160
What happens at the sagittal sinus
CSF is reabsorbed into the bloodstream
161
capillary-rich
membranes located in the roofs of the four brain ventri-
cles
choroid plexus
162
What causes hydrocephalus?
buildup of CSF in ventricles that lead to increased pressure and swelling, could be from obstruction of CSF flow or impaired absorption
163
What part of neurons create gray vs. white matter?
grey - neuron cell bodies, dendrites, unmyelinated axons
white - myelinated axons
164
What is the basic pattern of gray vs. white
matter in the cerebrum vs. spinal cord?
brain - grey matter is on outside, white is on inside
spinal cord - grey matter is on inside, white on outside
165
Know layers of the brain
skin of scalp, periosteum, bone of skull, dura mater, arachnoid mater, Pia mater,
166
layers of cranial meninges outside to inside
dura mater, arachnoid mater, pia mater
167
dura mater reflections purpose
help to separate and support different parts of the brain
168
2 reflections of dura mater
flax cerebri, tentorium cerebelli
169
What happens at choroid plexus to make CSF
filtration of blood plasma which creates the specialized fluid CSF
170
what style of
capillaries are there? at choroid plexus
fenestrated, have pores to allow rapid filtration of substances in the blood
171
Where are the tight junctions to create a blood-CSF barrier?
between ependymal cells of the choroid plexus
172
role of ependymal cells
actively participate in filtration, regulate what passes from the blood into the ventricles
173
what are the major brain arteries
internal carotid, vertebral, basilar, anterior, middle, posterior cerebral arteries
174
Contralateral leg weakness
anterior cerebral artery
175
Contralateral hemiparesis, especially in the upper limbs and face
middle cerebral artery
176
Locked-in syndrome (due to severe damage to the brainstem, causing paralysis of nearly all voluntary muscles except for eye movements).
Dizziness, nausea, or vomiting.
Loss of consciousness or coma (due to brainstem involvement).
Weakness and sensory loss in both sides of the body
basilar artery
177
Contralateral homonymous hemianopia (loss of vision in the same visual field of both eyes).
Visual agnosia (inability to recognize objects despite normal vision).
Memory problems (due to involvement of the temporal lobe, including the hippocampus).
posterior cerebral artery
178
What is a
hemorrhagic vs. ischemic stroke,
hemorrhagic stroke - blood vessel in or around the brain ruptures, leading to bleeding into the brain tissue creating pressure on brain structures
ischemic stroke - blockage or reduction in blood flow to a part of the brain leading to insufficient oxygen and nutrients for brain cells
179
what is carotid artery disease
carotid arteries become blocked or narrowed, usually due to plaque buildup, can happen easily where the int and ext carotid split, can easily cause stroke
180
How is the redundant blood flow of
the circle of Willis helpful?
it ensures adequate blood supply to large vessels even if one of the major arteries becomes blocked or narrowed
181
Where does the BBB exist along the brain?
vessels in brain, capillaries of brain which are specialized and tightly regulated
182
What features create the blood-brain barrier?
tight junctions between endothelial cells that line the blood vessels
183
How
do proteins, blood gasses, lipophilic molecules, glucose cross the BBB?
proteins and glucose transported actively
gasses and lipophilic molecules simple diffusion
184
How does the bloodCSF barrier compare with the blood brain barrier?.
BBB - formed by endothelial cells lining capillaries in brain, have tight junctions, no fenestrated capillaries
BCSF - located in choroid plexus, ependymal cells connected by tight junctions, has fenestrated capillaries for more freely exchange flow
185
Regulates vital autonomic functions: heart rate, breathing, blood pressure, vomiting
medulla oblongata
186
Regulates alertness, sleep-wake cycle, autonomic functions
reticular formation
187
ontrols the reflex of vomiting
vomiting center
188
Relays signals, regulates breathing, involved in sleep
pons
189
Sensory relay station, motor control, regulates consciousness
thalamus
190
Regulates homeostasis, pituitary hormone release, autonomic functions, emotions, sleep
hypothalamus
191
Produces melatonin, regulates sleep-wake cycles and circadian rhythms
pineal gland
192
Transmit motor signals from cerebral cortex to brainstem and spinal cord
cerebral peduncle
193
Visual processing, eye and head movement, eye tracking
superior colliculus
194
Auditory processing, sound localization
inferior colliculus
195
Coordinates voluntary movements, maintains balance and posture
cerebellum
196
Connects the left and right hemispheres, facilitates communication between them
corpus callous
197
How can vomiting be triggered by neural signaling from inner ear,
motion sickness and vertigo can cause conflicting signals from vestibular visual system which can cause nausea and vomiting
198
how can vomiting be triggered by neural signaling from GI tract
GI irritation, toxins, infections can activate chemoreceptors in the GI and send signals to VC
199
how can vomiting be triggered by neural signaling from CTZ
toxins, drugs, can cause detection of those chemicals in blood, thin BBB allows chemoc=recprots in brain to see them then send signal to VC
200
where is somatosensory cortex located
parietal lobe
201
Know what happens at the somatosensory cortex of the parietal lobe
receives input from sensory receptors throughout the body via thalamus
202
what happens at motor cortex
responsible for controlling and executing voluntary movements
203
major descending motor pathway
motor commands from cortex travel out to spinal cord the spinal nerves that innervate muscles for movement
204
It's the main motor pathway that carries signals from the motor cortex to the spinal cord, allowing you to voluntarily move your body.
corticospinal tract
205
path of CST
motor cortex, internal capsule, cerebral peduncle, pons, medulla oblongata, spinal cord to spinal nerves
206
why does right side of brain control left side of body
crossing over of CST at the medulla
207
long axons of pyrami-
dal cells form the
pyramidal tracts
208
Purely Sensory cranial nerves
I (Olfactory)
II (Optic)
VIII (Vestibulocochlear)
209
purely motor cranial nerves
III (Oculomotor)
IV (Trochlear)
VI (Abducens)
XI (Accessory)
XII (Hypoglossal)
210
mixed aka branciomeric nerves
trigeminal nerve, facial nerve, vagus nerve, glossopharyngeal nerve,
211
how does
a branchiomeric cranial nerve compare to a spinal nerve?
branchiomeric control specialized head and neck muscles
spinal serve general body movement and sensation
212
how are spinal nerves organized
in pairs, 8 pairs of cervical, 12 pairs thoracic, 5 pairs lumbar, 5 pairs sacral, 1 pair coccygeal
213
what are dermatomes
specific areas of skin innervated by same spinal nerve root, help localize nerve/spinal cord injuries
214
Produces tears to moisten and protect the eye; drains into nasolacrimal duct.
lacrimal Gland
215
Sebaceous glands at the rim of eyelids that secrete oil to slow tear evaporation.
tarsal glands
216
217
Thin mucous membrane lining the eyelids and front of the eye (except cornea); lubricates and protects.
conjunctiva
218
White, tough outer layer that maintains eye shape and protects inner parts.
sclerea
219
Transparent, curved front part of the eye that helps focus incoming light (major refractive surface).
cornea
220
Clear, flexible structure that changes shape to focus light on the retina.
lens
221
Watery fluid in anterior chamber (between cornea and lens); maintains pressure and nourishes cornea/lens.
aqueous humor
222
Gel-like substance in the posterior chamber (behind the lens); maintains eye shape and supports the retina.
vitreous humor
223
Contains ciliary muscle and secretes aqueous humor; connected to lens by suspensory ligaments
cilliary body
224
Contracts/relaxes to change lens shape for accommodation (focusing).
ciliary muscle
225
Colored part of the eye; controls the size of the pupil.
iris
226
Opening in the iris; regulates amount of light entering the eye.
pupil
227
Inner layer containing photoreceptors (rods & cones) that convert light into neural signals.
retina
228
Vascular layer between retina and sclera; supplies blood to outer retina and absorbs stray light.
choroid
229
Carries visual information from retina to the brain.
optic nerve
230
“Blind spot” where the optic nerve exits the eye; no photoreceptors.
optic disc
231
Area of high visual acuity in the central retina.
macula
232
Small pit at the center of the macula with the highest concentration of cones; sharpest vision
fovea
233
What tissue type allows the cornea and lens to be
transparent?
specialized tissues that lack blood vessels and have a regular arrangement of fibers that allow light to pass without scattering
234
Where does light bending (refraction) take place (not just the lens)?
cornea, lens
cornea is primary refractive surface of eye, lens fine tunes light that has already been bent by cornea
235
What happens to the cornea
if you wear contact lenses on your eyes for too long?
reduced oxygen supply, swelling, increased risk of infection, dryness and irritation
236
What is glaucoma
increased pressure on the optic nerve
237
what can cause glaucoma to happen
fluid in the eye doesn't drain properly, therefore the fluid increases and builds pressure
238
what is tear film
thin transparent layer of liquid that coats the surface of the eye
239
what is source of tear film secretions
lipid layer from tarsal glands, aqueous layer from lacrimal glands, mucus layer from conjunctiva
240
when ciliary muscle contracts, what happens to lens
tension is reduced on suspensory ligaments, allowing lens to become rounder, focuses on near objects
241
when ciliary muscle relaxes, what happens to lens
suspensory ligaments pulled tight, lens becomes flatter, allows focus on distant objects
242
What lens shape is required when focusing
on near vs. close objects?
near - more round, allows for more bending of light
far - lens needs to be flatter, reduces bending of light
243
basic arrangement of cells in retina
first cells to detect light - photoreceptors
cells transmit signals from photoreceptors to next layer of neurons - bipolar
ganglion - final receiving neurons going into optic nerve
244
last of the receiving neurons
ganglion
245
ganglion axons funnel where
into optic disc to make optic nerve
246
Know rods vs. cone receptors
rod - responsible for low light vision, sensitive to light, do not detect color
cone - responsible for color vision and detailed vision, less sensitive and function best in bright light, sensitive to red, green, blue WL
247
How is the fovea different in regard
to the receiving neurons along the retina and cones vs. rods?
receiving neurons - direct connection to bipolar cells meaning very high visual acuity
cones vs rods - fovea almost entirely made of cones
248
how is acuity of fovea
much higher than other areas of the retina due to high cone density and direct path
248
Know
difference between fovea and blind spot
fovea is an area of high acuity, blind spot has no photo receptors and is where the optic nerve exits the eye
249
loss of the ability to focus on close objects
presbyopa
250
what causes presbyopia
hardening of lens and weakening of ciliary muscles in eye
251
The visible part of the ear that collects sound waves and funnels them into the ear canal.
outer ear
252
A tube that carries sound waves from the pinna to the tympanic membrane (eardrum).
external auditory canal
253
Vibrates when sound waves hit it, transferring the sound energy to the ossicles (ear bones).
tympanic membrane
254
Three small bones in the middle ear that amplify sound and transmit vibrations from the eardrum to the inner ear.
ossicles (ear bones)
255
A membrane-covered opening that transfers vibrations from the stapes to the fluid-filled cochlea.
oval window
256
Another membrane-covered opening that helps equalize pressure in the cochlea.
round window
257
Connects the middle ear to the throat (pharynx), equalizing air pressure on both sides of the tympanic membran
Eustachian tube
257
A spiral-shaped organ that converts sound vibrations into electrical signals. It is filled with flui
cochlea
258
Located inside the cochlea, it vibrates in response to sound waves and plays a key role in hearing.
basilar membrane
259
A structure in the cochlea that interacts with the hair cells to help detect sound vibrations.
tectorial membrane
260
structures involved in sensory function only
inner hair cells
261
Amplify sound vibrations and improve hearing sensitivity by changing their length in response to sound, enhancing the movement of the basilar membrane.
outer hair cells
262
How are
high vs. low pitches of sound detected differently within the cochlea?
high pitches are detected near the base of cochlea, low pitch detected near the apex of the cochlea
263
what is conductive deafness
sound waves blocked from reaching inner ear, can be due to earwax buildup, ear infection,
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what is sensorineural deafness
damage to inner ear that is permanat
