Deck 1 Flashcards
insert lecture from October 4th here
start of digestive system
Ameloblasts originate from which layer and secrete what
inner enamel epithelium, enamel
Odontoblasts secrete…
predentin then dentin
parts of the enamel organ
1) inner enamel epithelium
2) outer enamel epithelium
3) stellate reticulum
4) Dental papilla
5) Odontoblasts
6) Dental sac
Striations in the dentin are called what?
dentinal tubules
How do salivary glands develop?
become inverted in the mesenchymal tissue and become a gland, invaginations of the oral epithelium into the lamina propria.
What is a salivary gland?
exocrine gland in the mouth that produces saliva which has digestive and lubricating properties.
two types of salivary glands
major and minor
Of the two salivary glands which is located further from the buccal cavity?
major
four major salivary glands?
parotid, mandibular, sublingual, zygomatic
four minor salivary glands?
labial, lingual, buccal
order of emptying ducts
striated–>intercalated–>seromucus
5 features of salivary glands
compound, exocrine, lobulated, merocrine, all secrete saliva (most are mixed seromucus glands)
Which animals experience conditioned reflex flow of saliva or salivate under the suggestion of food?
dogs and pigs?
Which animals experience unconditioned reflex flow of saliva or only salivate when food is present in their mouth?
Ungulates
Round secretory unit
acinus
elongated secretory unit
tubular
combination secretory unit
tubuloalveolar
Characteristics of mucous cells
compressed basal nuclei, cytoplasm doesn’t stain well, secrete mucin, wide lumen, pyramid shaped
Characteristics of serous cells
round basal nuclei, well stained cytoplasm, secretes enzymes and proteins, small lumen
What does the parotid salivary gland secret that initiates hydrolysis of carbohydrates?
alpha amylase
Release of bile and pancreatic juice is controlled by what structure?
Sphincter of Oddi
Sphincter of Oddi is stimulated by which hormones?
CCK or cholecystokinin
How can you ID alpha cells in islets of Langerhans?
immunostaining by antiglucagon stain
How can you identify islets of Langerhans in H&E?
Its lighter staining
Which structure is pancreatic juices secreted?
Into the duodenum
Parenchyma has what two major cell types?
Hepatocytes and phagocytotic Kupper cells
What are the blood channels called that separate hepatocytes?
sinusoids
Islet of Langerhans have three primary endocrine functions, what are the three cells types and what hormones do they secrete?
Alpha - glucagon
Beta - Insulin
Delta - somatostatin
What is the primary function of the fetal liver?
Fetal hematopoiesis
What is the name of the male gametes?
spermatozoa
Which two glands secrete the majority of the seminal fluid?
Seminal vesicles and prostate gland
Purpose of the bulbourethral glands of Cowper
to secrete lubricating fluid for the passage of semen through the urethra during ejaculation
Endocrine component of testis is made up of two cell types that produce what two hormones?
Leydig cells - testosterone
Sertoli cells - estrogen
Tunica albuginea
the white fibrous covering the testies, collagen is the main component and is covered by the tunica vaginalis
Testicular lobules are made up of what smaller structure?
seminiferous tubules
Seminiferous tubules are surrounded by the …
basal lamina
Classify epithelium of the testis parenchyma
stratified epithelium
Function of sertoli cells
sustentacular cells called “nurse cells” that support developing gametes
what shape is the nucleus of the sertoli cells?
triangular
What is the process of sperm maturation?
spermatogonia type A–>.spermatogonia type B –> primary spermatocyte–>secondary spermatocyte–>spermatids–>spermatozoa
What cells create the blood-testis barrier?
sertoli cells - sertoli cells are held together by occluding tight junctions
BIological significance of blood testis barrier
create immune privileged area, they must have their own immunity or else the body will attack and destroy them as though they were foreign.
Which structure during sperm maturation is a haploid cell? (1n DNA)
spermatid
At which period does chromosomal cross-over occur?
primary spermatocyte - this is biologically significant to creating genetically different cells
metamorphosis takes place between which two maturation phases?
spermatids to spermatozoa
What structure contains hyaluronidase enzymes?
the acrosomal cap
Unnecessary cytoplasm off the spermatozoa is engulfed by which cells?
sertoli cells
what structure extends to produce flagellum of the spermatogonia?
centrioles
Why is genetic diversity important?
- disease resistance
- adaptability to environmental changes
What is the mechanism of erection
vasodilation of blood vessels in erectile tissue (corpus cavernosum and corpus spogiosum)
