W2 - Glands + Supporting Tissues (lecture)

Question 1

What are glands and what are they involved in?

Answer 1

Invaginations of epithelium, involved in secretion

Question 2

All glands have a continuous basal rate of secretion, what can change this?

Answer 2

Neuronal/hormonal influences

Question 3

What are the two components of an exocrine gland?

Answer 3

Secretory component and duct system (branched/unbranched)

Question 4

What are the 4 ways the secretory component can be structured in an exocrine gland?

Answer 4

Tubular, acinar, coiled or branched

Question 5

Simple tubular exocrine glands - where are they found and what is the structure?

Answer 5

Large intestine - straight lumen with secretory cells lining entire duct

Question 6

What is the only example of simple coiled tubular glands and why is a different portion seen in each section taken?

Answer 6

Sweat glands - they coil in 3D

Question 7

Where are simple branched tubular glands found and what is their structure of tubular portions?

Answer 7

Stomach mucus and there’s multiple tubular secretory portions that come together to form one duct

Question 8

Endocrine glands lose their connection to the epithelial surface during development, where do they then release their secretions instead?

Answer 8

Directly into the blood

Question 9

Why are most endocrine glands composed of multiple types of secretory cells?

Answer 9

They release multiple hormones

Question 10

What 3 things are endocrine glands usually controlled by?

Answer 10

Metabolic factors (e.g.) glucose, NTMs and HMs

Question 11

Most endocrine glands contain clusters of secretory cells, do they have their own BM or do they share one?

Answer 11

Each cluster has their own

Question 12

Where do endocrine glands release hormones?

Answer 12

Into intercellular spaces

Question 13

What is the origin on all supporting tissues?

Answer 13

Mesodermal

Question 14

What two things make up the supporting tissues?

Answer 14

Specialised cells and extracellular matrix

Question 15

What makes up the extracellular matrix? (ECM)

Answer 15

Ground substance and fibres

Question 16

What component of supporting tissues determines it’s physical properties?

Answer 16

ECM

Question 17

When using H+E, what colour do the fibrous proteins and ground substance stain?

Answer 17

Fibrous - pink, GS - pale/colourless ish

Question 18

What form is collagen secreted as before polymerisation in the ECM?

Answer 18

Tropocollagen

Question 19

Type 1 collagen is found in the dermis, tendons and where else? (3)

Answer 19

Ligaments, bone and fibrous supporting tissues

Question 20

Type 2 collagen is found in hyaline cartilage, how does this appear in ground substance?

Answer 20

As fine fibrils

Question 21

Type 3 collagen is found in the liver, bone marrow and lymphoid organs, what is their structure and what colour do they appear when stained with silver?

Answer 21

Delicate branching and they stain black

Question 22

Where does type 4 collagen form a mesh like structure?

Answer 22

Basement membrane

Question 23

What is it about type 7 collagen that links to basement?

Answer 23

Anchoring fibrils link to basement membrane

Question 24

What do fibroblasts and myofibroblasts do?

Answer 24

Fib - secrete ECM, myofib - contraction + secretion of ECM

Question 25

What do chondrocytes, osteocytes and adipocytes do?

Answer 25

Chond - secrete ECM in cartilage, osteo - secrete ECM in bone, adi - store and metabolise fat

Question 26

Describe the nuclei, cytoplasm and the look of fibroblasts in collagen fibres (when stained)

Answer 26

Nuclei is condensed and elongated, very little cytoplasm, look very dense and pink when stained

Question 27

Give examples of where loose and dense supporting tissues are found

Answer 27

Loose - bowel submucosa, dense - muscle fascia

Question 28

What is the interface between support tissues and parenchymal cells?

Answer 28

Basement membrane (BM)

Question 29

What is the BM called in nerve and muscle tissue?

Answer 29

External lamina

Question 30

How does the BM regulate maturation?

Answer 30

Is a barrier to downward growth

Question 31

What three components of BM are made by epithelial cells and which one is made by fibriplasts?

Answer 31

Epithelial cells - collagen 4, entactin + laminin. Fibroblasts - fibronectin

Question 32

What are the 3 layers of the BM?

Answer 32

Lamina lucida, densa and reticularis

Question 33

What layer of the BM connects to the epithelial cells and which to the connective tissues?

Answer 33

Lamina lucida - epithelial cells, lamina reticularis - connective tissues

Question 34

Why does adipose tissue need a rich blood supply?

Answer 34

Important for releasing energy

Question 35

What do adipocytokines do?

Answer 35

Regulates body mass and influences metabolism

Question 36

White adipose tissue is typically found in the dermis, what are it's 2 functions?

Answer 36

THermal insulator and cushioning against shock (e.g. in kidneys)

Question 37

Why does white adipose tissue stain pale, with very little colour at the edges?

Answer 37

MOstly occupied by lipids, nucleus and cytoplasm is pushed to the edge

Question 38

Adipocytes have 4 receptors, what for?

Answer 38

Insulin, cortisol, growth hormone and noradrenaline

Question 39

Brown adipose tissue is found in newborn mammals, what is their role?

Answer 39

Temperature regulation

Question 40

Brown adipose tissues is arranged in lobules separated by fibrous septae, what is contained in this fibrous septae?

Answer 40

Blood vessels and nerves