Histology Flashcards
Describe the 3 layers of blood vessels?
Tunica intima- inner single layer of squamous epithelial cells supported by basal lamina and thin connective tissue layer
Tunica media- predominantly smooth muscle
Tunica adventitia- supporting connective tissue
Why are larger arteries termed elastic arteries?
They have many sheets of elastic fibres in their tunica media to provide recoil
Large vessels need their own blood supply… this is termed?
Vasa vasorum
Arterioles have barely any
tunica adventitia
Capillaries consist of _______ and a ________
They often have ______ which have ____
endothelial cells
basal lamina
pericytes
contractile properties
Capillaries drain into ______ they are referred to as venules when _________
post capillary venules
they begin to acquire intermittent smooth muscle cells
Veins have a thinner _____ than in arteries
Largest veins have a thick ____
tunica media
tunica adventitia
Erythrocytes have a ______ shape
They are not true cells as they don’t have a ______
biconcave disc
nucleus
Neutrophils are _______ they have a ________ nucleus and are increased in _______
granulocytes
multi lobed
bacterial infections and steroid use
Lymphocytes are _______ with a ______ they are increased in _____
Agranulocytes
round large nucleus (in comparison to the cytoplasm)
viral infections
Monocytes are _____ and have a _______ nucleus that is ______ shaped, they increase in _____________
agranulocytes
non-lobulated
kidney bean
atypical infections and cancers
Eosinophils are ______ and have prominent granules with affinity for __________ they have a ______ nucleus and increase in ____________
granulocytes
red dye eosin
bilobed
parasitic infections and allergies
Basophils are ________ with a ______ nucleus (often obscured by granules) they stain intensely ____ and are rarest of granulocytes they play a role in ______
granulocytes
bilobed
blue purple
allergic reactions
The structure of the endocardium
endothelium
basal lamina
thin layer of collagen fibres
layer of denser connective tissue
The structure of the myocardium
bundles and layers of contractile cardiac muscle fibres that are individually surrounded by delicate collagen connective tissue with a rich capillary network. Intercalated discs pass through the fibres.
The structure of the epicardium
single layer of flattened mesothelium
basal lamina
fibroelastic connective tissue and in some places adipose tissue
coronary vessels are typically embedded in this adipose tissue
Structure of pericardium
fibrous= tough fibrocollagenous connective tissue Serous= simple squamous mesothelium backed by a basal lamina and connective tissue
Structure of heart valves?
outer endothelial layer with a basal lamina
layer of collagen and elastin fibres
a lamina fibrosa (core of connective tissue) which is continuous with the fibrous skeleton
leaflets of mitral and tricuspid valves are anchored to papillary muscle by collagenous strands called chord tendinae
there are no blood vessels
Structure of pacemaker cells?
smaller than myocytes
embedded in more extensive matrix of connective tissue
histologically appear pale
Structure of purkinje fibres?
These are larger than myocytes
Found in subendocardial layer just deep to the endocardium
they appear pale with an even paler centre.