Epithelium & Connective tissue

Question 1

What are the 4 tissue types?

Answer 1

1. Epithelium: binds surfaces
2. Connective: binds cells together to form a functional framework
3. Muscle: Key exitable tissue
4. Neural

Question 2

What is the form and function of simple squamous tissue?

Answer 2

Form - thin, flat and delicate in a single layer
Function - Found on well protected organs where rapid absorption must take place (alveoli) or to form smooth surfaces (blood vessels)

Question 3

What are the characteristics of stratified squamous cells and where are they commonly found?

Answer 3

• Made from layers of cells and so are more resistant and can withstand some mechanical stress. Held together by connective tissue
• Found on skin where it is keratinized, also found in the oral cavity

Question 4

What is the form of simple cuboidal cells and what are their function?

Answer 4

• Single layer of cube-like cells with large nuclei

- Found in places where absorption takes place (e.g kidney tubules)

Question 5

What are simple columnar cells and what is their function?

Answer 5

• Longer cells with nuclei restricted to the base in a single layer
• Often found on absorbing/secreting tissues where they protect from chemical stress
• Sometimes contain cilia in order to increase the surface area

Question 6

What is pseudostratified columnar tissue?

Answer 6

• Appearance of layers however all cells are attached to the bottom
• Often ciliated for the movement of substances (e.g nasal cavity)

Question 7

What is the glandular epithelium?

Answer 7

Any epithelium that secretes substances, from a single cell to an organ

Question 8

What are the different types of glands?

Answer 8

• Simple unbranched
• Compound branched
• Tubular
• Alveolar (sacs)
• Tubuloalveolar (sac connected to a tube)

Question 9

What is the complexity of a gland related to?

Answer 9

The complexity of the substances it secretes

Question 10

What are the 3 classifications of connective tissue?

Answer 10

Connective tissue proper, supporting connective tissue and fluid

Question 11

What are the characteristics of connective tissue proper?

Answer 11

• Formed from extracellular fibres (e.g collagen) suspended in a viscous base of glycoproteins
• Formed from mixed cell populations
• Can be dense or loose

Question 12

What are the characteristics of supporting connective tissue?

Answer 12

• Densely packed & uniform

- Strong

Question 13

What is the fluid connective tissue and give 2 examples

Answer 13

• Cells suspended in fluid

- Blood and lymph

Question 14

What are collagen fibres formed from?

Answer 14

• 3 alpha-helical strands linked together to form fibrils which H-bond to form a fibre

Question 15

Where are collagen fibres found?

Answer 15

• Major components of tendons & ligaments

- Underpins all connective tissue

Question 16

What are the properties of reticular fibres?

Answer 16

• Similar components to collagen however with a more mesh-like structure
• Used to hold a functional tissue within place in an organ

Question 17

What is the function of elastic fibres?

Answer 17

Allow connective tissue to have flexibility

Question 18

Name 5 different types of tissue found in connective tissue proper

Answer 18

1. Fibroblasts
2. Fibrocytes
3. Adipocytes
4. Immune cells
5. Mesenchymal cells

Question 19

What is the function of fibroblasts?

Answer 19

• Most common type of cell found
• Secrete pro-collagen to make collagen
• Also secrete hyaluronan which creates viscous base solution

Question 20

What are fibrocytes?

Answer 20

Differentiated fibroblasts which maintain and repair connective tissue

Question 21

What is the defining property of adipocytes?

Answer 21

Contain lipid droplets

Question 22

What are mesenchymal cells?

Answer 22

The stem cells of the connective tissue

Question 23

What are the properties of regular dense connective tissue proper?

Answer 23

• Tightly packed & aligned with the force exerted on the tissue
• Strong in one direction but often weak in another
• High levels of collagen

Question 24

What are the properties of irregular dense connective tissue proper?

Answer 24

• Meshlike structure counteracts stress in multiple directions
• Forms capsule around many organs

Question 25

What is the function of elastic dense connective tissue proper?

Answer 25

Allows stretching of connective tissue

Question 26

What are the 2 types of loose connective tissue?

Answer 26

Adipose - insulation and packing to absorb shock

Reticular tissue - Supporting framework for cells within tissues

Question 27

How is the matrix in cartilage different to that found in collagen?

Answer 27

• More gel like due to proteoglycans formed from proteins and chondroitin sulfates
• Chondrocytes create the matrix by secreting chondroitin sulfates

Question 28

What are the 3 types of cartilage?

Answer 28

Hyaline - most common, resistant and dense
Elastic - made of collagen and elastic fibres, can change shape and return to form
Firbocartilage - heavily packed with a high resistance to mechanical stress, found in the joints

Question 29

How does bone differ from cartilage?

Answer 29

Collagen is surrounded by calcium salts which are secreted by osteoblasts