anterior - lingual tonsil formed by the submucous adenoid collections.
lateral - palatine tonsils and adenoid collections near the auditory tubes.
posterior - pharyngeal tonsil on the posterior wall of the pharynx.
between main masses are smaller collections of adenoid tissue.
Tonsils
Palatine Tonsils
the "tonsils", lateral wall of oropharynx
covered by stratified squamous epithelium
numerous crypts (10-20) infolds of surface epithelium
Afferent lymph vessels absent
Efferent lymph vessels are present
Lingual Tonsils
lamina propria root of tongue
covered by stratified squamous epithelium
salivary glands and skeletal muscle are directly adjacent
Pharyngeal Tonsils
adenoids or nasopharyngeal tonsils, upper posterior part of throat
covered by a pseudostratified ciliated epithelium with goblet cells
Peyer's Patch
Peyer's Patch
located in the ileum
Peyers patches (ileocolonoscopy)
Peyer's Patch (histology)
microfold cells or M-cells (transport gut lumen organisms and particles to immune cells across the epithelial barrier).
About Peyer's Patch
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