2. Basic Histology Quiz: General Connective Tissue Created by: Maureen Bain Start

3. Question 1 Classify the type of epithelium shown in this image (A) Why do you think this type of epithelium is most suited to this location? Classify the type of Connective tissue indicated by B. What are the defining features of this type of connective tissue? What do you think C might represent? Answers at end of Quiz BackNext

4. Question 2 Identify tissues A, B and C Figure 2 : Low power view of digital pad (dog) Area shown in Figure 3 Connective tissue A B C Answers at end of Quiz BackNext Area shown in Figure 4 Area shown in Figure 5

5. Question 3 How would you classify this epithelium? (Remember there are multiple layers of keratinized cells above the ‘living layers’). What separates the epithelium from the underlying connective tissue (CT)? Figure 3: Medium and high power views of Surface epithelium shown in figure 2 - digital pad Answers at end of Quiz BackNext

6. Question 4 By comparing the proportions of cells to fibres, how would you classify this type of connective tissue? (Note that the ground substance surrounding the cells and fibres is not visible with H&E staining) Give reasons for your answer. What types of fibres are mainly found in this type of CT.? These fibres are secreted and maintained by fibrocytes. You should be able to see the nuclei of fibrocytes in between the CT fibres in the high power view. Figure 4- Connective tissue underlying the surface epithelium in figure 2 (med and high power) Answers at end of Quiz BackNext

7. Question 5 This is the digital cushion of the food pad section shown in Figure 2. This is composed of adipose tissue. Are the cells associated with this tissue examples of Unilocular or Multilocular Adipocytes? What is the function of the digital cushion? You should be able to see some examples of simple coiled tubular secretory units within the adipose tissue (D). These represent cross sections through sweat glands. Are sweat glands exocrine or endocrine glands? What is the main difference between an exocrine and endocrine gland? Figure 5 : Adipose tissue associated with the digital cushion shown in Figure 2 (medium view) D Answers at end of Quiz BackNext

8. Question 6 In the low power view, locate the large villi which project into the lumen of this part of the digestive system. A high power view of one villus is also shown. What type of epithelium lines this villus (see high power view). The surface epithelium of each villus is supported by loose connective tissue (see high power view). This type of connective tissue is characterized by having more cells in proportion to fibres and ground substance. Figure 6: Jejunum (part of the small intestine) Low and high power views) lumen Answers at end of Quiz BackNext

9. Question 7 Identify the different cell types shown in Figure 7. What is the function of each of these cell types? Macrophages are described as being active phagocytes- What does this mean? Which of these cells types is /are not regarded as a resident type of CT cell? Figure 7: Different cell types associated with generalised connective tissues A B C D Answers at end of Quiz BackNext

10. Question 8 What type of connective tissue cell is illustrated in this high power view of dense irregular connective tissue? Answers at end of Quiz BackNext

11. Answers 1. Stratified squamous epithelium High mechanical abrasion due to passage of food leads to wear and tear at surface. Cells in basal layer multiply and move upwards towards the surface. Rate of loss = rate of new cells forming Dense irregular CT Collagen fibres numerous and go in all directions. Few cells and little gel like matrix visible. An exocrine gland duct leading to the surface from the secretory cells which are embedded in the underlying ct. (not visible) 2. A= epithelium, b= connective tissue, c= adipose tissue 3. Stratified squamous keratinized epithelium Basement membrane (remember all epithelium lies on a basement membrane!) 4. Again dense irregular CT Lots of fibres going in multiple directions, few cells and low amount of gel Collagen (type 1) Key thing here is that the cells lie between the fibres. 5. Unilocular -one big lipid droplet per cell. Shock absorption Exocrine- have secretory unit and duct leading to surface. Exocrine have ducts, endocrines have no ducts and rely on blood vascular system to deliver secretion to target tissue. 6. Simple columnar cells – note there are also a large numbers of pale staining cells associated with the surface epithelium –these are goblet cells. 7. A=fibroblast Production extracellular matrix., tissue repair etc B= macrophage, Defence- phagocyte C=mast cell, Defence- vasodilation D=plasma cell, Antibody production Scavenger cells- go around eating up bacteria and cellular debris Plasma cell 8. Fried egg shape = mast cell Back to quiz