cvs histology formatives Flashcards
what is the diff btwn elastic and muscular arteries
arteries closest to heart eg aorta, pulmonary = elastic
all others = muscular
name some examples of muscular arteries
radial
splenic
what is present in arteries but not veins
external elastic lamina
what are pericytes
contractile cells that wrap around the outside of capillaries
what regulates capillary diameter
pericytes
what do capillaries comprise
endothelial cells resting oo a basement membrane
are capillaries fenestratd
some are eg kidney/liver but most are not
what are fenestrations
gaps in the endothelial layer
how many um thick are arterioles
100 um
what is the diff btwn endometrium, perineurium and epineurium?
endoneurium: present btwn individual axons
perineurium: surrounds group of axons to form fascicles
epineurium: binds fascicles together to form nerve fibres
what binds fascicles together to form nerve fibres
epineurium
what surrounds groups of axons to form fascicles
perineurium
what produces myelin
Schwann cells
how is myelin produced
when a single Schwann cell wraps itself repeatedly around part of an axon
is myelin 1 layer of Schwann cell membrane
no, it is multiple
what is a devoid of myelin
nodes of Ranvier
what is the name for the small pockets of cytoplasm left behind during Schwann cell myelination
schmidt-lanterman incisures
how many axons are myelinated by a single Schwann cell
1
how many Schwann cells support unmyelinated axons
many
where are the cell bodies of motor neurones
in the grey matter of the spinal cord
where are the cell bodies of sensory neurons
dorsal root ganglion
where are the cell bodies in grey matter of cord and in adjacent sympathetic ganglia
sympathetic neurons
where are parasympathetic neuron cell bodies
in brain and local ganglia
what proportion the blood is WBC/platelets
1%
what is the diff btwn plasma and serum
serum = plasma with clotting factors removed
what % of blood is RBC
43%
what % of blood is plasma
56%
where are erythrocytes first prod in utero
yolk sac
then liver
then bone marrow
where is haematopoiesis in adults confined to
flat bone marrow
proximal ends of humeri n femurs
where are rbc destroyed
liver n spleen
what is the prominent leukocyte
neutrophil
what are the 3 granulocytes n respective %
40-75% neutrophils
5% eosinophils
0.5% basophils
what are the 2 agranuocytes and respective %
20-50% lymphocytes
1-5% monocytes
what do eosinophils play a role in
defence against parasitic infections
where do b lymphocytes mature in adults
bone marrow
what does a lymphocyte look like histologocially
roundish nucleus surrounded by thin rim of pale blue cytoplasm w no granules
how are basophils and eosinophils similar and different
both bear receptors to IgE
but antagonistic in function
what do basophils release
histamine
what do eosinophils do
counteract histamine action
what are antibodies secreted by
plasma cells
do neutrophils bear IgE receptors
no
what do monocytes give rise to (5)
- tissue macrophages (everywhere)
- kupffer cells (liver)
- osteoclasts (bone)
- antigen presenting cells (everywhere)
- alveolar macrophages (lungs)
what are platelets
membrane bound fragments of megakaryocyte cytoplasm
where does erythropoiesis occur away from
bony trabeculae
what is the outermost layer of the heart
visceral pericardium
what are the layers of the heart (outer to inner)
visceral pericardium
epicardium
myocardium
endocardium
what is the parietal pericardium
fibros sac that contains the heart
what type of epithelium is the pericardium
simple squamous (mesothelium)
where else is mesothelium found
pericardium
pleura
peritoneum
what are cardiac myocytes like?
- branching cells
- each with a single nucleus
- myofibrils in register
- appear striated
which myocytes secrete ANP
atrial myocytes
what is the cytoplasm of purkinje fibre cells rich in
glycogen
where are purkinje fibre cells located
immediately below the endocardium
what is the prime function of purkinje fibre cells
to conduct cardiac impulse
how do myocytes of SAN differ from normal myocytes
no intercalated discs
which cells line the surface of cardiac valves
vascular endothelial cells
what are the nodules of Arantius
nodules of fibroelastic tissue on centre of free edge of each of cusps in aortic n pulmonary valve
which yellow/brown pigment accumulates in cardiac myocytes w increasing age
lipofuscin: “wear and tear” pigment
do the coronary arteries have an external elastic lamina
yes
which layer of the heart do the coronary arteries run in
epicardium
what are weibel-palade bodies
storage granules found in cytoplasm of endothelial cells: contain VWF
which tissues don’t have lymphatics
cartilage
eye
bone marrow
where does erythropoiesis occur away from
bony trabeculae
what is the outermost layer of the heart
visceral pericardium
what are the layers of the heart (outer to inner)
visceral pericardium
epicardium
myocardium
endocardium
what is the parietal pericardium
fibros sac that contains the heart
what type of epithelium is the pericardium
simple squamous (mesothelium)
where else is mesothelium found
pericardium
pleura
peritoneum
what are cardiac myocytes like?
- branching cells
- each with a single nucleus
- myofibrils in register
- appear striated
which myocytes secrete ANP
atrial myocytes
what is the cytoplasm of purkinje fibre cells rich in
glycogen
where are purkinje fibre cells located
immediately below the endocardium
what is the prime function of purkinje fibre cells
to conduct cardiac impulse
how do myocytes of SAN differ from normal myocytes
no intercalated discs
which cells line the surface of cardiac valves
vascular endothelial cells
what are the nodules of Arantius
nodules of fibroelastic tissue on centre of free edge of each of cusps in aortic n pulmonary valve
which yellow/brown pigment accumulates in cardiac myocytes w increasing age
lipofuscin: “wear and tear” pigment
do the coronary arteries have an external elastic lamina
yes
which layer of the heart do the coronary arteries run in
epicardium
what are weibel-palade bodies
storage granules found in cytoplasm of endothelial cells: contain VWF
which tissues don’t have lymphatics
cartilage
eye
bone marrow
