Anemia week VHA Flashcards
What type of tissue is blood?
connective
Describe a typical RBC
non-nucleated
biconcave
lack organelles
How long do RBCs survive for?
~120 days
What are the 2 classes of WBCs?
granulocytes and agranulocytes
Granulocytes
neutrophils, eosinophils and basophils
Agranulocytes
lymphocytes and monocytes
What do lymphocytes look like on stain?
small
basically a very dark dot
Distinguishing feature of macrophages on stain
large
kidney shaped nucleus
Distinguishing feature of neutrophils on stain
multi-lobed nuclei with pale pink cytoplasm
Distinguishing feature of eosinophils in cytoplasm
stain pink
bilobed nucleus
Where are eosinophils often found?
the colon
Distinguishing features of basophils
not often that you see them on smears
when you do, it looks like many blue stipples
What are the two components of the spleen?
red and white pulp
Where are venous sinuses found?
in the red pulp of the spleen
What type of collagen makes up the venous sinuses?
type III collagen
List the flow of blood through the spleen
Splenic artery
Central artery
White pulp
Red pulp
Venous sinuses
Splenic vein
What is the pathway of blood flow through the spleen called?
closed circulation of the spleen
What are the venous sinuses of the spleen?
barrel-shaped, dilated vascular spaces whose endothelial cells are separated by slits
these slits function as a way to remove effete RBCs
Autosplenectomy
occurs in sickle cell
vaso-occlusion of the venous sinuses leads to splenic damage
Conducting portion of respiratory system
structures that deliver air to points of gas exchange
Describe the epithelial layer of the respiratory tract mucosa
ciliated psudeostratified columnar epithelium with goblet cells
What is the region of the lung that participates directly in respiration called?
pulmonary acinus
this is where gas exchange occurs
What is includes in the pulmonary acinus?
bronchioles and alveoli
What is the epithelial layer where actual gas exchange occurs?
thin squamous cells
*there is a gradual transition from ciliated pseudostratified columnar cells to thin squamous cells in the respiratory tract
Are mucus secreting glands found in the respiratory segments of respiratory tract?
No since they would obstruct gas exchange
Mucus secreting glands are only found in the conducting segments of the respiratory tract
Macrophages in the lungs
referred to as dust cells
often are in the airspaces
Elastic fibers
important in the respiratory tract
provide recoil after each expansion of the alveoli from inhaled air to allow PASSIVE exhalation
What type of cells compose the walls of the alveoli?
pneumocytes (type I and type II)
Which pneumocyte can you see on slides?
type II
normally in a line near the alveolar space
Difference between type I and II pneumocytes
Type I: large surface area to facilitate gas exchange
Type II: cuboidal and secrete surfactant
What cells contain surfactant?
type II pneumocytes
Breakdown of pancreatic cell function
90% of function is exocrine (secretes alkaline bicarbonate sodium into duodenum)
other function is endocrine (insulin + glucagon)
What structure can the pancreas often be confused with histologically? What distinguishes the pancreas?
parotid gland
pancreas has islets of Langhorn
How can you determine the small intestine vs. the colon since they both have crypts?
the small intestine has villi
Where is the brush border?
small intestine
What is the brush border made of?
actin
Where are most goblet cells found in the GI tract?
in the colon
but they are still present in the small intestine
What helps to distinguish small intestine from colon?
Brunner’s glands, villi, and Peyer’s patches
Brunner’s glands
submucosal glands found in the small intestine that secrete bicarbonate to neutralize stomach acid
Peyer’s Patches
large, submucosal lymph nodes found in the ileum of small intestine
M-cells
epithelial cells that are closely associated with Peyer’s patches below them
cannot visualize M cells well on stain
How can you differentiate different glands?
serous acinar is darker
mucinous is more white space because nucleus gets pushed up to the sides
