Lab 3 Connective tissue (2) Cartilage,Bone and Blood smear Jun Zhou(周俊）, Ph.D & M.D School of Medicine,Zhejiang University

Slides 1.cartilage ( No.3 trachea) 2.Bone (No.5) 3.Blood smear (picture drawing)

Trachea (No.3) Hyaline Cartilage C-shape hyaline cartilage Location of hyaline cartilage:articular surface of synovial joints, rings of trachea, plates in the bronchi Trachea (No.3)

Hyaline Cartilage Trachea(No.3)：H&E ×40 This a photomicrograph of a routine H&E preparation of hyaline cartilage shows its general features. Note the extensive extracellular matrix that separates a sparse population of chondrocytes. Resistant to compression, provides cushioning, smooth and low friction surface for joints. Trachea(No.3)：H&E ×40

Trachea：Hyaline Cartilage H&E ×400 capsule lacuna perichondrium The DCT overlying the perichondrium, from which new cartilage cells are derived. Appositional growth and interstitial growth, the latter is responsible for the formation of isogenous groups. Mature chondrocytes with clearly visible nuclei reside in the lacunae. A dark-staining capsule or territorial matrix immediately surrounding the lacunae. Isogenous groups Trachea：Hyaline Cartilage H&E ×400

Bone Haversian system(osteon) Central canal Circumferential lamella Interstitial lamella Bone lacuna Bone canaliculus Bone is a sepcialized CT characterized by a mineralized extracellular matrix. Calcium phosphate, in the form of hydroxyapatite crystals, is deposited along the collagen fibrils and in the proteoglycan ground substance. Bone serves as a storage site for calcium and phosphate, which can be released to the blood to maintain homeostatic levels. During internal remodeling of bone, the involved destruction of osteons left remnants and become the intertitial lamellae. Silver ×100

Bone：Silver ×400 Haversian system(osteon) Central canal Bone lacuna Bone canaliculus Osteons are essentially cylindrical structures.The long axes of the osteons are oriented parallel to the long axis of the bone.At the center is osteonal canal. Because the organic materials is not retained in ground sections,the Harversian canals and other spaces will appear black, as they do here, if filled with air or other dye. Bone：Silver ×400

Bone：Silver ×100 perforating (Volkmann’s) cannals Blood vessels reach the Haversian canals from the marrow through other tunnels called perforating (Volkmann’s) cannals. In some instances, as here, Volkmann’s canals travel from one Harversian canal to another. Volkmann’s canals can be distinguished from Harversian canals in that they pass through lamellae, whereas Haversian canals are surrounded by concentric rings of lamellae. Bone：Silver ×100

Stained with Wright’s stain. Blood smear: A drop of blood is placed directly on a glass slide and spread over its surface with the edge of another slide. Stained with Wright’s stain. Try to find an area with evenly distributed cells and normal cell shapes.

Blood smear：Wright ×400 Erythrocytes: 7-8um Biconcave disc Stain uniformly with eosin Neutrophil: proportion - 50-70%; Most numerous Multilobed nucleus Pale pink granules The method of producing a blood smear: a drop of blood is placed directly on a glass slide and spread over its surface with the edge of another slide. A smear from peripheral blood.The cells are mainly erythrocytes. Blood smear：Wright ×400

Eosinophils. Blood smear：Wright ×400 8-10 microns morphology 2-4% 8-10 microns morphology bilobed nucleus large, uniform eosinophil granules. Blood smear：Wright ×400

Blood smear：Basophil Giemsa stain ×400 Basophils. Proportion 0.5% morphology - large, irregular basophil granules obscure the nucleus The basophil granules are very large and irregularly shaped. Granules obscure the nucleus. Blood smear：Basophil Giemsa stain ×400

Blood smear：Wright ×400 Lymphocyte: Intensely stained nucleus Possess a slight indentation Small amount of cytoplasm Pale blue Blood smear：Wright ×400

Monocyte: Blood smear：Wright ×400 nucleus ovoid to kidney shaped blue-gray Cytoplasm Blood smear：Wright ×400

Platelets: Blood smear：Wright ×400 Small speck-like objectives Aggregated into small groups From megakaryocytes in myeloid tissue. Platelets are indicated by arrows. Some leukocytes are present. Blood smear：Wright ×400

Blood smear：Wright ×400

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