Histology- From Exam 3 to final Flashcards
(164 cards)
1
Q
Why should you not inject drugs into legs of birds?
A
This is because drugs will be diverted through kidney immediately befoer your drug has had a chance to work. Normally pectoral system is ideal
2
Q
What is an issue with coelomic epithelium, pronephric or mesonephric epithelium in lower vertebrates?
A
less efficient
3
Q
What are the large pink structures indicated with the arrow?
A
Thyroid follicle ( Hormones are here bound to extracellular pool of protien)
4
Q
What is the trophic hormones of the pars distalis?
A
GH, Prolactin, LH, FSH, ACTH
5
Q
Why is the urinary system important?
A
Without urinary system their are very limited ways to get rid of wastes.
6
Q
What is some histological / anatomical differences of reptiles? (Chelonians)
A
- Have urinary bladder
- Tortoises can collect and reabsorb water ( like a canteen)
- Turtles reabsorb Na + helps with flotation
7
Q
Why is the urethra surrounded by the external striated muscle sphincter? What kind of muscle is it?
A
Voiding must be voluntary. Skeletal muscle.
8
Q
What are the 5 layers of the cornea?
A
Anterior epithelium
Basement Membrane
Substantia propria ( corneal stroma)
Posterior limiting (descements) membrane
Posterior epithelium ( corneal endothelium)
9
Q
What is the job of the neurophypophysis?
A
The site for hormone storage and release. (site of hormone secreting neurons are located in hypothalamus) ( NO SYNTHESIS HERE)
10
Q
What kind of arteries are found in the glomerulus?
A
Afferent & efferent arteries
11
Q
What is a negative feedback mechanism?
A
Products of stimulated cell inhibit further hormone secretion.
12
Q
What is paracrine signaling?
A
Substance is released by cells and affects cells within short distance.
13
Q
What maintains the ventral portion of the middle ear?
A
tympanic bulla
14
Q
What is a common site of hyperplasia/ neoplasia in older horses ( and sometimes dogs)?
A
adenohypophysis
15
Q
What is the role of PTH?
A
Increases blood calcium concentration
This causes bone to activate osteoclasts, intestines to absorb calcuim, and kidneys to block reabsorption of phosphorus and enhance reabsorption of calcium
16
Q
What can you find in the visceral layer of the bowmans capsule?
A
Podocytes
17
Q
What kind of cells are found between glomerular capillaries? What do they do?
A
Mesangial cells. They are phagocytic
18
Q
What cell type is found within the thick capsules of the kidney?
A
mesothelial
19
Q
What is the arrow pointing to in this image of thyroid gland?
A
C cells
20
Q
What is the function of the adrenal medulla?
A
synthesize catecholamines (epinephrine [adrenaline], norepinephrine [noradrenaline], and dopamine.
21
Q
What stimulates erythropoetin production in the kidneys?
A
Decreased oxygen saturation
22
Q
What kind of glands ( not specific types, just overall) are found in the endocrine system?
A
Ductless Glands
23
Q
What are the zones labeled by the numbers in this image?
A
- ) Zona Glomerulosa
- ) Zona Fasciculate
- ) Zona Reticularis
24
Q
What is the function of the aqueous humor?
A
Formed by non-pigmented cells of the ciliary processes
• Nourishes cornea (glucose)
• Maintains intraocular pressure and therefore some of
the ocular shape
- CONSTANT DRAINAGE required
- GLAUCOMA – increase in intraocular pressure
25
What is gout?
build up of uric acid in tissues. Uric crystals build up and damage not only kidneys but other tissues. Can be caused by dehydration.
26
What is the tapetum lucidum?
- light reflecting layer that can be of either cellular or fibrous type. This layer is absent in swine and in humans. This light reflecting layer is believe to increase light perception under conditions of poor illumination (superior night vision)
- present in nocturnal animals, especially carnivores, and in some deep sea animals.
27
What are some histological/ anatomical differences in Bird urinary systems?
Kidney: Cortical (Reptilian)
- Smaller Glomerulus (dense mesangium)
- No loop of henlee
Medullary: Mammalian
- Larger glomerulus with loop of henry
NO RENAL PELVIS
SPINAL NERVES RUN THROUGH KIDNEY
Ureter: Pesudostratified columnar cilliated epithelium
NO URINARY BLADDER (Urodeum in cloaca)
28
What is cranial nerve 8?
vestibulochoclear nerve
29
Why is the presence of spinal nerves in the kidneys of birds important clinically?
Kidney disease can cause pressure on nerves and cause issues walking/ paralysis
30
What are the cells in this image?
Chief cells
31
Parathyroid gland cells are arranged....
in dense cords/ nests around abundant capillaries
32
What are hematological indicators of kidney function?
BUN and Creatnine
33
What hormones does the Adenohypophysis release:?
TSH - Stimulates thyroid to release thyroid hormone (ie. T3, T4)
PRL- acts on mammary glands to stimulate milk production
FSH/ LH : Acts on gonads to stimulated development of gametes.
GH- acts on all body tissue (especially connective tissue) to stimulate growth
ACTH - Acts on adrenal cortex to produce corticosteroids (ie. cortisol)
34
What is the normal cortex medulla ratio ?
1:1(2):1
35
What is the function of the ear?
1. Collect auditory stimuli
2. Transduce the mechanical stimuli
3. Transmit nerve impulses to CNS
36
What is some histological / physical differences of amphibians?
Histological:
- Glomerular line rather than cortex vs medulla
- Hematopoietic tissue in kidney
Physiological:
Nitrogen excreted as:
* Ammonia (aquatic stages/species)
* Urea (terrestrial stages/species)
* Uric acid (arboricoral species – tree frogs)
- Unable to concentrate urine
Plasma= urine (USG not helpful)
Frogs have urinary bladders. Will also void immediately when being lifted.
37
What is the cell indicated by the black line in this photo?
Ganglion cell (looks like a neuron)
38
What is this black arrow pointing at?
Residual Rathkes pouch
39
What is the renal pelvis and what does it become?
Pseudostratified columnar to transitional epithelium
- Becomes the ureter (1 per kidney)
40
What is this epithelium? Where is it?
Transitional
41
What is this arrow pointing at?
Parathyroid gland sitting on top of thyroid gland
42
What are the three tunics of the eye? What can you find in each?
Fiberous tunic (sclera/ cornea)
vascular tunic ( iris, cilliary body, choroid)
Retina (pigmented layer, neural layer)
43
What cells of adenohypophysis are considered basophils?
- ACTH, TSH, FSH, LH
- Basophilic granules in cytoplasm.
Pars intermedia and pars tuberalis are composed mostly of basophils
44
What are the different poles of the glomerulus?
Urinary pole: More urine is accumulated in this area
Vascular pole: Area where the cells of the glomerulus meet the surrounding cells.
45
What is the black line indicating in this image?
Chromaffin cells
46
What type of cells are present in the thyroid?
Follicular cells ( produce T3/T4 and secretion stimulated by TSH)
Parafollicular cells ( C cells ) which produce calcitonin
47
What is an indication you are looking at a feline kidney?
Abundant adipose tissue
48
What are the layers of the urethra?
Mucosa: Transitional epithelium to stratified squamous to skin. Lamina propria
Adventitia: loose connective tissue
Surrounded by external striated muscle sphincter.
49
What are the layers of the ureter?
Mucosa (transitional epithelium)
- LP often very thin, mucus glands in first bit of ureter in horses
Muscularis (muscular layer)
- smooth muscle (inner longitudinal, middle circular, outer longitudinal (not as distinct)
Adventitia
- Loose connective tissue sometimes with adipocytes.
50
What is the order from least toxic to most toxic of the product of breaking down nitrogen?
1. ) Urea
2. ) Uric Acid
3. ) Ammonia
51
What is the brown color caused by in this image?
Uroplakins
52
What are these arrows pointing at ?
Tubules filled with uric acid (BIRDS CAN DIE FROM GOUT)
53
What does Renin do? What is the result?
Renin- Cleaves angiotensinogen to result in angiotensin. This will increase blood pressure.
54
What is the difference between a distal convoluted tubule and a proximal convoluted tubule in the kidneys?
Proximal convoluted has a brush border (microvilli)
Distal Convoluted tubules do not have a brush border
55
What are hormones?
Chemical messengers produced by endocrine cells and deliver to target cells.
56
How much hormone is stored within the thyroid follicle?
several weeks worth
57
What are the arrows pointing at?
A.) Cortex
B.) Medulla
58
What is important about kidney tissue in amphibians?
Kidney is more important than bone marrow. Their is hematopoietic tissue in kidney.
59
What is inflammation of the cornea called?
Keratitis
60
What is the name of epithelium which invaginates into capillaries?
Bowmans capsule
61
What is some histological / anatomical differences of reptiles? (Snakes)
- Males Sexual segment of kidney
protien + lipid secretion= copulatory plug
regresses with castration (androgen dependent)
- no urinary bladder
62
What is included in the renal corpuscle?
Glomerulus + Bowman’s capsule + extras
63
What does the proximal convoluted tubule reabsorb?
- Water
- Protiens
- Electrolytes
\*\* RICH IN FAT IN CATS\*\*\*
\*\*\* LONGER THAN DISTAL CONVOLUTED TUBULES \*\*\*
64
What is produced in the zon fasciculata? What stimulates it?
Production of mineralocorticoids hormones (Aldosterone), which maintain sodium and
potassium levels in extracellular body fluid. Stimulated by ACTH
65
What do collecting ducts become? What happens at the papilla?
Collecting ducts become papillary ducts. These ducts open onto renal pelvis at the papilla.
- Simple to pseudostratified columnar epithelium
66
What are the arrows pointing at in this picture?
Proximal Convoluted tubules
67
What else is produced by the kidney?
Erythropoietin
68
What is a meibomian gland tumor? Are they malignant?
Often benign adenomas
69
Why don't birds have urinary bladders?
Expell to stay lighter for flight
70
What controls the ammount of light that the retina is exposed to?
Sphincter pupillae muscle ( Parasympathetic innervation)
Dialator Pupillae muscle ( Sympathetic innervation)
71
What is sokme histological / anatomical differences of reptiles? (Lizards)
- urinary bladder in some species
- colon runs between kidneys in iguanas (Nephromegaly may result in colonic obstruction)
72
What connects the neurohypophysis to the hypothalamus?
infundibular stalk
73
What is the pituitary gland referred to as and why?
The pituitary is often called the "master gland" of the body because it produces
hormones that regulate other endocrine glands, as well as, have direct effects on
target tissues
74
What are the layers of the urinar bladder?
Mucosa ( transitional)
- LP/ Sub mucosa (separated by thin musclularis mucosa)
Muscularis
- Smooth muscle ( inner longitudinal, middle circular, outer longitudinal)
Serosa ( mesothelial cells)
Adventitia(neck): Loose connective tissue
75
What innervates the cilliary body?
Cranial nerve III (ocular motor nerve)
76
What produces mucus in the ureter of the bird?
no goblet cells, epithelium produces mucus on own.
77
What is the corneoscleral junction?
limbus ( its microvasculature provide metabolites for cornea)
78
Why is there muscle in the urethra?
needs muscle to help movement of urine, gravity helps but needs peristalisis like movement of urine to void from renal pelvis.
79
What is the arrow pointing to in this image of thyroid gland?
Follicular cells
80
What is included in the renal pyramid?
Cortex + Medulla + Papilla
81
What is glaucoma? Is it permenant?
Increase of intraocular pressure due to decrease of aqueous fluid drainage, can cause blindness/ vision impairment due to compression of retina.
- It is permenant, nerve cells will not regenerate.
82
When looking at histological sections of the kidneys cortex what are the green arrows and what are being labeled with the orange arrows?
Green arrow: Pars Convoluta - longitudinal
Orange Arrow: Pars Radiata
83
What is an important landmark of zona fasciculata?
Thickest layer
84
What is the function of chromaffin cells and what are their key histological characteristics?
modified postganglionic sympathetic neurons that secrete catecholamines
(epinephrine or norepinephrine).
- Clusters and irregular trabeculae of polygonal cells with granular, basophilic cytoplasm
85
What is the functions of the urinary system?
- Maintain composition of body fluids at a
homeostatic constant
- Remove waste
- Protein metabolism waste: nitrogen
86
What are the glands that are part of the endocrine system?
- Pituitary
- Adrenal
- Thyroid
- Parathyroid
87
What is the cornea?
is the anterior portion of the
eye. This is an avascular, transparent
convex-concave lens.
- remarkable regeneration capacity
- has 5 layers
- Richly supplied by sensory nerves ( opthalmic branch of cranial nerve V)
88
What are the major components of the cochlear duct?
Tectorial membrane – vibrated by sound wave energy
Organ of Corti
- Hair cells – Stereocilia
- Phalangeal cells – support
- Pillar cells – moved by sound wave energy and displace hair cells against tectorial membrane.
Basilar membrane – vibrated by sound wave energy
Stria vascularis – produces endolymph
89
What is important to note about turtles?
They will void bladder the moment you lift it so be ready if sample collection is needed.
90
Where are photoreceptors located? what will lesions in the visual pathway cause?
Retina
Blindness/ vision impairment
91
What is the pars intermedia?
an interface between pars distalis and neurohypophysis that contains neumorous colloid protien filled cysts ( known as rathkes cysts)
92
What is the job of adenohypophysis?
Glandular cells synthesize and release hormones, which is controlled by neurons in hypothalamus. Releasing and inhibiting hormones are released by hypothalamic neurons and passed into adenohypophysis through portal system
93
What determines uni- multilobar kidneys?
Uteric duct
94
What is T4 and T3 bound to?
Thyroglobulin
95
What are the arrows pointing to in this image?
Glomeruli
96
What is the sequence of renal embryology and the animals which stop at each step?
Pronephros: All vertebrates
Mesonephros: Fish, Amphibians (less function)
Metanephros: Reptiles, Birds, Mammals ( Most evolved, most function)
97
What is the function of the endocrine system?
regulates growth, reproduction, metabolic activities and constantly works to maintain homeostasis through hormone action.
98
What is the renal portal system in birds?
Brings blood from lower legs, lower body, and hind gut. Amt is species dependant, and Adrenalin diverts blood bypassing kidneys.
99
What is the arrow pointing at?
Colloid (protein)-filled cysts (Rathke’s pouch
100
What is the kidney capsule made of?
Fiberous connective tissue, removable at necropsy or dissection.
101
What are iridic granules or corpora nigra?
are present in equids and ruminants at the dorsal and ventral pupillary margins. Their function is to protect the eyes from the damaging effects of bright sunligh
102
What is a very broken down explaination to each part of urinary system?
Kidneys- Filter blood to remove waste
Ureters- Move filtered waste (urine) to bladder
Bladder- Stores Urine
Urethra- releases urine from the body
103
What are the sinusoidal capillaries?
Extensive network that receives hormones from acidophils and basophils
104
What determines eye color?
• Pigment or iridial melanin present in the stromal cells determines eye color.
105
What is the function of the thyroid gland?
Produce T3 and T4, which acts on almost all cells of body increasing metabolic rate. Also produces calcitonin (which decreases blood calcium concentration)
106
What kind of capillaries are in the nephrons? What is on top of the capillaries?
Fenestrated Capillaries, Podocytes sit on top
107
What are the parts of the cochlear apparatus?
Vestibularcochlear nerve
Spiral ganglia
Scala vestibuli
cochlear duct
scala tympani
108
What has long axons that extend into pars nervousa?
Hypothalamus
109
What is the macula densa?
Segment of tubule between afferent and efferent arteries close to glomerular vascular pole with specialized epitheliym ( which will tell juxtaglomerular apparatus if it must produce renin to increase blood pressure)
110
What is the names of the lense layers from most external to most internal?
1. ) Lens capsule
2. ) Lens epithelium, simple columnar
3. ) Differentiating Lens fibers
4. ) Mature lense fibers
111
What is the Juxtaglomerular apparatus?
segment of afferent artery where smooth muscle is replaced by modified cells that produce renin
112
Which urine is more irritating? Birds or Mammals?
Bird urine is rich in uric acid which makes it more irritating the mammalian urine
113
What are 2 parenchymal cells associated with the parathyroid gland?
Chief cells: produce parathyroid hormone (PTH)
- Oxyphil cells: function not known, likely an inactive chief cell. Contains eosinophilic granular cytoplasm (large numbers of mitochondria).
114
What is indicated by the white arrowtop in this image?
Collecting duct
115
What do distal convoluted tubules become? What is their function?
Distal convoluted tubules become collecting ducts
- Simple cuboidal to columnar epithelium
- Regulate K excretion/reabsorption
116
What is the loop of henle and what does it absorb?
Cuboidal - Squamous – Cuboidal epithelia
(descending, loop, ascending) ! Water + Na, Cl & other electrolytes
117
What is produced in the zona reticularis? What stimulates its production?
- Sex hormones (androgens). Stimulated by ACTH
118
What animals have smooth muscle underneath their kidney capsule?
Horse
Dog
Pig
Ruminant
119
What kind of axons are present in the pars nervousa?
non myelinated.
120
What is the lacrimal gland?
Tear film moistures, lubricate, and protect the eyes.
◦ Lacrimal glands have tubuloalveolar acini composed of secretory cells filled with small granules.
◦ Myoepithelial cells are present at the bas
121
What is the purpose of location of kidney and its parts?
```
close proximity between blood and
filtration units (glomeruli
```
122
What is the loop of henle?
- Cuboidal - Squamous – Cuboidal epithelia (descending, loop, ascending)
- Water reabsorption continues
123
What is the germ layer of the trigone in the bladder?
Mesoderm
124
What is the germ layer of the urinary system?
Mesoderm mostly, bladder and urethra epithelium is endoderm ( transitional cells)
125
What will most of the baldder wall have?
Smooth muscle
126
What is autocrine signaling?
Substance is released and affects same cells.
127
Who is more susceptible to inner ear infections? What is the concern about middle ear infections?
Pigs. Middle ear infections can ascend into inner ear and cause meningitis/ encephalitis.
128
What protien waste metabolism product is excreted in each species listed?
1. ) Exotics
2. ) Fish
3. ) Mammals
1. ) Exotics- Uric acid
2. ) Fish- Ammonia
3. ) Mammals- Urea
129
What does the urinary space lead to ?
lumen of proximal convoluted tubule
Star = urinary space
130
What are the cells being pointed at?
Pituicytes: glial-like cells, supporting cells
131
What is produced in the zona glomerulosa in the adrenal cortex? What is it stimulated by?
roduction of mineralocorticoids hormones (Aldosterone), which maintain sodium and
potassium levels in extracellular body fluid. Stimulated by angiotensin II
132
What are the parts of the vascular tunic?
Iridocorneal angle
A. Iris is located anterior to the lens; separates the anterior and posterior chambers.
B. Ciliary Body: suspends the lens, contains smooth muscle for accommodation; has processes covered by secretory epithelium.
C. Choroid: provides vascular supply to the optical retina. Contains pigment and, in many species, the TAPETUM LUCIDUM.
133
In the glomerulus, what does basement membrane do and what type of collagen makes up the glomerulus?
Basement membrane is involved in filtration.
Collagen type IV ( window screen like)
134
What are filtration slits?
Areas between podocyte pedicles.
They regulate passage of many small protiens
135
What are the divisions of the ear?
External: auricle/ pinna + external auditory meatus
Middle ear: tympanic cavity. Connected to pharynx through eustachian tube.
Inner ear: Composed of membranous labyrinth enclosed in temporal bone. (Hearing + equilibrium)
136
What cells are in the adrenal medulla?
- Chromaffin cells
- Ganglion cells
- Medullary Cells
137
What kind of capillaries are typically found in the endocrine glands?
Fenestrated ( facilitates diffusion of hormones into blood)
138
What is endocrine signaling?
Substance is released and enters circulation and travels a long distance to reach their target cell.
139
Name the labeled areas.
A.) loop of henle
B.) Papillary Ducts
3.) (Both red arrows) are RBC's within capillaries
140
What is the function of pars distalis in the adenohypophysis?
Produce, store and release trophic hormones in
response to hypothalamic-pituitary-target organ
axis
141
How many parathyroid glands are there?
Usually 4 ( 2 external, 2 internal).
142
What is the function of the adrenal cortex?
synthesize steroid hormones (corticosteroids).
143
what is a distal convoluted tubule?
Cuboidal epithelium no brush border
- Reabsorption of electrolytes
144
Why is nitrogen broken down into its least toxic form for excretion?
More toxic requires more water to excrete in less toxic way.
145
What is the difference histologically between Acidophils and Basophils?
- Acidophils will stain pink, basophils will stain purple.
146
What is albinism?
partial or total lack of melanin pigment.
Albinos have melanocytes but lack genes for tyrosinase
- from recessive alleles
- Albinos more susceptible to light induced retinopathy
- Red eyes from total lack of melanin, hb in rbc
147
What is the specific functions of the kidneys?
- Electrolyte, water & acid-base balances
Na, K, P, Ca
- Excretion of waste & excess water
-Excretion of bioactive substances (drugs)
Pre-metabolized or not
- Renin secretion\*
Angiotensinogen cleaved into angiotensin I. Blood pressure regulation. Fluid + electrolytes + waste through glomerulus. Water & electrolytes reabsorbed in tubules
- Erythropoietin secretion\*
Response to low O2, stimulates RBC production/maturation
- Vitamin D metabolism (activation)
- Gluconeogenesis to help the liver.
During starvation or fasting: aa’s to glucose
148
What is the function of the sclera?
◦ Protects of the eye
◦ Maintains the shape of the eye
◦ Provides insertion points for tendons of extraocular muscles
149
What are the three hormone classifications. What is an example of each?
- Proteins and Polypeptides (insulin, glucagon, FSH)
- Amino acid derivatives (thyroxine, and epinephrine)
- Steroids and fatty acids (progesterone, estradiol, and testosterone.
150
What forms a protective barrier in transitional uroepithelium?
Uroplakins - which are protien membranes, impermiable but flexible, and can be identified with IHC. Helpful for tumor identification
151
What cells of adenohypophysis are considered acidophils?
Growth Hormone and Prolactin
Eosinophilic granules in cytoplasm.
152
What are the parts of the Glomerular filtration barrier?
- Endothelium (fenestrated capillary)
- Basement membrane
Shared endothelium+podocyte
- Filtration slits
Between podocyte pedicles
153
What does the neurohypophysis (pars nervousa) contain?
- mainly axons from hypothalamic neurons, but stores + secretes oxytocin and antidiuretic hormones.
154
What is the prominant cell in the adenohypophysis?
Melanotrophs
(which secrete melanocyte stimulating hormone MSH)
155
What does the pituitary gland develop from?
Neural (diencephalon ) (becomes neurohypophysis) and the Oral (rathkes pouch) ( becomes adenohypophysis) ectoderm
156
What does non pigmented cells of cilliary body do?
Nonpigmented = ion transporting, moving fluid from vascular stroma to posterior chamber ( Forming aqueous humor)
157
What is the hormones released by the neurohypophysis?
Oxytocin, Antidiuretic hormone.
158
What is the lense?
- Clear biconvex structure containing a capsule, anterior epithelium,
and lens fibers or body.
• Formed by epithelial cells which elongate by forming lens fibers.
• The lens is suspended by the zonular fibers from the ciliary
processes.
• The lens has an EQUATOR in the same plane as the equator of the
eyeball.
* The lens loses its vascular supply after development.
* The lens grows throughout life.
* WHEN THINGS GO WRONG: Lenticular sclerosis and cataracts are common defects.
159
What kind of feedback mechanism does the anterior adenohypophysis use?
Negative feedback mechanism, Neurohypophysis does not.
160
What is the carea cribrosa?
The combined nerve fiber layers converge on the optic disk to form the optic
nerve which penetrates the sclera via several perforations known as the area cribrosa.
161
What are ceruminous glands?
Located within the skin of the external acoustic canal
* Simple, coiled, tubular apocrine glands
* Ear wax, also known as cerumen, is a mixture of viscous secretions from sebaceous glands, sloughed skin cells, and less-viscous ones from modified apocrine sweat glands (ceruminous glands)
This will trap foreign materials
162
How many parts are there to the sensory/ optical retina?
10 layers. Optical retina is held in place by vitreous body.
163
What is the portion within the dotted lines? What is the purple arrow indicating?
Dotted line: Macula densa
Purple arrow: Juxtaglomerular cells
164
Label all parts of the hypophysis of the pituitary gland
a. ) Pars Nervousa
b. ) Pars Distalis
C) Stalk
D.) Pars Tuberalis
E.) Hypothalamus
F.) Pars Intermedia
