Tissues - Connective Tissue

Question 1

What are the structural elements of CT?

Answer 1

• cells: widely separated, manufacture CT matrix

- matrix: determines properties of CT

Question 2

What is the prefix for immature cells?

Answer 2

Blast

Question 3

What is the prefix for mature cells?

Answer 3

Cyte

Question 4

What are the types of connective tissue fibres?

Answer 4

Collagen
Elastic
Reticular fibres

Question 5

Collagen fibres

Answer 5

• very strong
• high tensile strength (resistant to breaking under tension)
• slightly wavy appearance when not under tension, some give but not elastic

Question 6

Elastic fibres

Answer 6

• finer than collagen

- capacity to stretch and recoil

Question 7

Reticular fibres

Answer 7

• very fine form of collagen
• not visible in most photomicrographs
• forms supportive network/mesh

Question 8

Dense connective tissue

Answer 8

• predominant fibre type is collagen
• fibre occupy more space than cells or ground substance
• cells are fibroblasts and fibrocytes (mostly)

Question 9

Dense regular connective tissue

Answer 9

• fibres all aligned in same direction
• thick bundles of collagen
• not much stretch but bends
• poor blood supply
• fresh tissue is white
• found in ligaments and tendons

Question 10

Dense irregular connective tissue

Answer 10

• same Elements as dense regular
• but fibres are arranged in many different directions
• examples: dermis of the skin

Question 11

What can areola tissue convert to?

Answer 11

Adipose tissue

Question 12

Adipose tissue

Answer 12

• aerolar CT that is modified to store fat droplets
• very well vascularised
• adipocytes
• very little matrix as cells occupy much space

Question 13

What are the functions of adipose tissue?

Answer 13

• stores nutrients
• absorbs shock
• insulates
• holds some organs in place (structural fat)

Question 14

Blood

Answer 14

• erythrocytes and leucocytes in plasma

- fibres are soluble in plasma and only evident during clotting

Question 15

What is the function of blood?

Answer 15

• transport (O2, nutrients, waste , hormones)
• protection (WBC, platelets, antibodies)
• regulation (pH, body temp, fluid distribution)

Question 16

What are the three types of cartilage?

Answer 16

Hyalin
Elastic
Fibrocartilage

Question 17

What is cartilage intermediate between?

Answer 17

Dense CT and Bone

Question 18

What are the cells of cartilage called?

Answer 18

Chondroblasts and Chondrocytes

Question 19

What is most cartilage covered by?

Answer 19

Periochondrium (dense irregular CT)

Question 20

What is the function of cartilage?

Answer 20

Provides shape and support
Template form bone growth
Resists compressive forces

Question 21

Where is hyalin cartilage located?

Answer 21

Synovial joints, trachea, growth zones of skeleton

Question 22

Where is elastic cartilage located?

Answer 22

Epiglottis, external ear

Question 23

Where is fibrocartliage located?

Answer 23

Pubic symphysis, intervertebral discs

Question 24

What do chondroblasts do?

Answer 24

Actively deposit matrix

Question 25

What do chondrocytes do?

Answer 25

Maintenance

Question 26

What is an epiphyseal line?

Answer 26

Mature, represents bony joint

Question 27

What is an epiphyseal plate?

Answer 27

Growing (made of cartilage)

Question 28

Is cartilage vascular or avascular?

Answer 28

Avascular - limit to thickness

Question 29

Characteristics of loose areolar CT

Answer 29

- all 3 fibre types and fibrocytes (+ macrophages, WBC, adipocytes) - abundance of reticular fibres - fibres run in multiple direction allows for movement in many directions - ground substance is semi-fluid/gelatinous

Question 30

What is bone made up of?

Answer 30

1/3 organic: collagen fibres + protein and carbohydrate complexes 2/3 inorganic: calcium salts

Question 31

What do calcium salts do in bone?

Answer 31

Give ridgidity

Question 32

What does collagen did in bone?

Answer 32

Resistance to bending and twisting forces (in its absence bone will shatter)l

Question 33

What are the types of cells in bone?

Answer 33

Osteoblasts: lay down bone tissue, non mitotic Osteocytes: maintenance, remodelling

Question 34

Characteristics of compact bone

Answer 34

``` Osteon: concentric rings of bone Highly vascular Concentric lamellae: inner layer Circumferential layer: outer layer - collagen fibres alternate directions to resist breaking in many directions ```

Question 35

How are osteocytes nourished?

Answer 35

Nourished by diffusion | - facilitated by gap junctions between cells

Question 36

When are fibres produced?

Answer 36

G1 of cell cycle

Question 37

Scurvy

Answer 37

Lack of vitamin C in the diet | Vitamin C is a co-factor for 2 enzymes crucial to collagen formation

Question 38

Which connective tissue covers bone?

Answer 38

Periosteum (dense irregular CT)

Question 39

What are the cells in cartilage?

Answer 39

Chondroblasts and chondrocytes

Question 40

Cartilage is __________

Answer 40

Avascular, realises on diffusion | No nerve supply, good for covering joints

Question 41

What is the function of loose areolar CT?

Answer 41

- widely distributed packing material of the body | - binds body parts but allows them to move freely over one another

Question 42

What is the function of loose CT?

Answer 42

- provides a support mesh for cells in delicate, cellular organs like liver, spleen, bone marrow and lymph nodes