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1. Build a dichotomous key to all the tissues you have seen in the lab. For this

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Question

1. Build a dichotomous key to all the tissues you have seen in the lab. For this, you can use any of their morphological characteristics (under the microscope) but not their physiological functions.

Tissues seen in the lab:

Epithelia: simple squamous, simple cuboidal, simple columnar, pseudostratified columnar, stratified squamous, stratified cuboidal and columnar, transitional, Globet cells.

Connective: adipose, areolar, hyaline cartilage, fibrocartilage, fibrocartilage, elastic cartilage, bone, blood

Muscle: smooth, muscle, cardiac muscle, skeletal muscle

Nervous: neuron cells, glial cells

Explanation / Answer

Epithelia:

Simple squamous epithelium - single layer, flattened cells

Simple cuboidal epithelium : single layer, cube shaped cells

Simple columnar epithelium : single layer, elongated cells

Pseudostratified columnar epithelium : single layer, elongated cells

Stratified squamous epithelium : many layers, top cells flattened

Stratified cuboidal epithelium : 2-3 layers, cube shaped cells

Stratified columnar epithelium :top layer of elongated cells, lower layers off cube shaped cells

Transitional epithelium: many layers of cube shaped cells and elongated cells

Goblet epithelium : unicellular or multicellular.

Connective tissue ---

Areolar: consist of fibroblasts, macrophages, adipocytes, mast cells, plasma cells

Loosely arranged collagen, reticular and elastic fibers an gelatinous ground substance.

Adipose : adipocytes, fibres are reticular and collagen

Closely packed cells with a small amount of gelatinous ground substance.

Hyaline cartilage : chondrocytes, collagen fibers

Limited ground substance, dense and gel matrix.

Elastic cartilage : chondrocytes, elastic fibers

Limited ground substance, flexible but firm gel matrix.

Fibrocartilage: chondrocytes, collagen fibers

Limited ground substance intermediate between Hyaline cartilage and dense connective tissue.

Bone--- osteoblasts and introduced cells ,collagen fibres

Blood --- erythrocytes, leukocytes, platelets

Muscle ----

Striated skeletal muscles have characteristic cross-striations which are due to the regular arrangement of contractile elements, the sarcomeres.multinucleated.

Cardiac muscle are strained. Branched and shaped like fibres cross linked to each other. One nucleus per cell.

Smooth muscles, as their name implies, do not possess cross-striations. They are generally lighter in color than striated muscle.one nucleus per cell.

Neurons and global cells are both composed of cell bodies and cell processes.