lab exercise 6a-2 connective tissue nervous muscle
TRANSCRIPT
Lab Exercise 6a-2
Connective Tissue
Nervous
Muscle
Classification of connective tissues
Connective Tissue
Connective tissue proper Fluid connective tissue Supportive connecting tissue
Connective tissues
Connective tissue proper Loose connective tissue
Areolar Adipose Reticular
Dense connective tissue Dense regular Dense irregular Elastic tissue
Fluid CTBlood
Supporting CTsCartilageHyaline cartilageElastic cartilageFibrocartilage• Bone
Areolar tissue
A loose CTP
Areolar
Areolar: what to look for
Fibroblasts Collagen fibers Elastic fibers Mast cells and macrophages
Found? Throughout body, under dermis, divides skin from underlying tissues
Fibroblasts
Resting fibroblasts typically have so little cytoplasm that the cells appear, by light microscopy, as "naked" nuclei
Fibroblast
Adipose tissue
Another lose CTP (note nucleus)
Adipose: what to look for
Lots of cytoplasm Slim nuclei pushed off the side
Found? You know where
Reticular tissue
The third type of loose CTP
Reticular tissue
Reticular: what to look for
Reticular fibers (network)
Found? Internal framework in many sort organs (liver, spleen) supporting the parenchyma
Dense CTP
Dense regular – strength in one direction Dense irregular – strength in all directions Elastic tissue - pliable
Dense regular
Dense regular: what to look for
Thick parallel bundles of collagen Small fibroblasts in between bundles
Found? Tendons, ligaments, deep fascia.
Dense irregular
More dense irregular
Dense irregular: what to look for
Mesh of collagen fibers (irregular looking) Interspersed fibroblasts
Found? Dermis of skin, periosteum, perichondrium
Elastic tissue
Elastic tissue: what to look for
Elastic fibers (instead of collagen fibers) in large bundles
Fibroblasts
Found? Between vertebrae, in blood vessel walls (underneath endothelium)
Fluid CT
Blood
Blood: what to look for
RBCs White blood cells (darker): monocytes,
lymphocytes, granulocytes Platelets
Supportive CT
Cartilage – gelatinous, padding Hyaline cartilage Elastic cartilage Fibrocartilage
Hyaline cartilage
Glasslike because fibers not visible
More hyaline
There are collagenous and elastic fibers lying in the cartilage matrix but they are invisible because their “refractive index” is the same as that of the matrix (like cornea)
More hyaline
Hyaline cartilage
Hyaline
Hyaline cartilage (lavender matrix), with perichondrium (pink) outside it. The latter is a dense regular collagenous CT. Cartilage cells = chondrocytes, and they are lying in the lacunae.
Hyaline cart.: what to look for
Chondrocytes and lacunae No visible fibers Where? Most joints, nasal septum
Elastic cartilage
Elastic Cartilage
Elastic cart: what to look for
Many elastic fibers in matrix Chondrocytes in lacunae May be stacked up
Fibrocartilage
Fibrocartilage: what to look for
Irregular, wispy collagen fibers Chondrocytes
Found? Intervertabral discs of spine, pads in knee joint
Supportive CT: Bone
Detail of lacuna, showing radiating canaliculi. Tissue fluid from the capillaries and connective tissue of the Haversian canal can seep through these spaces and channels, bringing nutrients to the stellate osteocytes residing there.
Bone: what to look for
Osteon (whole circular structure) Concentric lamellae (of matrix) Central canal (at center of lamellae) Osteoblasts Osteocytes in lacunae Canaliculi
Found? Bones!
Nervous tissue
Neuron smear Large, pyramidal cell bodies Long processes extending out
Nervous Tissue
Figure 4.10
3 Types of Muscle Tissue
Skeletal muscle: large body muscles responsible for movement
Cardiac muscle: found only in the heart
Smooth muscle: found in walls of hollow, contracting organs (blood
vessels; urinary bladder; respiratory, digestive and reproductive tracts)
Muscle Tissue: Skeletal
Long, cylindrical, multinucleate cells with obvious striations
Found in skeletal muscles that attach to bones or skin
Muscle Tissue: Skeletal
Figure 4.11a
Muscle Tissue: Cardiac
Branching, striated, uninucleate cells interlocking at intercalated discs
Muscle Tissue: Cardiac
Figure 4.11b
Muscle Tissue: Smooth
Sheets of spindle-shaped cells with central nuclei that have no striations
Found in the walls of hollow organs
Muscle Tissue: Smooth
Figure 4.11c
Exercises
Look at all slides Draw an example of each tissue on paper provided 11 connective tissues:
6 CTP (3 loose, 3 dense) 1 Fluid CT (blood) 4 Supportive CT (3 cartilage, 1 bone)
Neurons 3 Muscle tissues
SkeletalStriatedSmooth
Turn in on Thurs 10/25
7 drawings from 6a-1 Epithelia 15 Drawings from 6a-2 Connective+ Review sheet for lab 6a