Breast histology*

Question 1

how many lobes is the secretary breast tissue made of

Answer 1

15-25

Question 2

what each lobe consist of

Answer 2

compound tubulo acinar gland which drains via a series of ducts leading to the nipple

Question 3

what is adjacent to the secretory lobules and what is it surrounded by

Answer 3

dense fibrous tissue surrounded by adipose tissue

Question 4

what are suspensor ligaments of cooper

Answer 4

increased condensations of fibrocollagenous tissue that extend to the dermis of the skin and support the breast

Question 5

where do the lactiferous ducts start and end

Answer 5

branch from each lobule and end at the end of the nipple

Question 6

what do terminal ducts lead into and then what and then

Answer 6

interlobular collecting duct and then extra lobular collecting duct which then leads to lactiferous duct. this then leads to the nipple and passes through a sinus

Question 7

what is the lactiferous sinus

Answer 7

the duct expands for a short distance and then gets smaller again - allows a reserver for milk to build up for breastfeeding

Question 8

what is the lining of larger ducts

Answer 8

columnar epithelium

Question 9

what is the lining of secretary acini

Answer 9

cuboidal or low columnar epithelium

Question 10

what are both larger ducts and secretary acini surrounded by

Answer 10

myoepithelial cells - contractile epithelial cells

Question 11

what do breast glands look similar to

Answer 11

sweat glands

Question 12

what is the nipple covered by

Answer 12

high pigmented keratinized stratified squamous epithelium

Question 13

what is the core of the nipple

Answer 13

dense irregular connective tissue mixed with bundles of smooth muscle

Question 14

why is smooth muscle in the core of the nipple

Answer 14

for nipple erection

Question 15

what can be seen in a transverse section through the nipple (2)

Answer 15

lactiferous sinuses

sebaceus glands which produce oil to help with the protection of the nipples during breastfeeding

Question 16

what happens to the lining of the lactiferous duct as it reaches the surface

Answer 16

changes from being one cell thick to stratified columnar epithelium to stratified squamous epithelium

Question 17

what happens to the epithelial cells during the luteal phase

Answer 17

increase in height

lamina of ducts becomes enlarged and small secretions appear in ducts

Question 18

changed in the mamary glands during the first trimester

Answer 18

elongation and branching of the smaller ducts and proliferation of the epithelial cells of the glands and the myoepithelial cells

Question 19

what changes occur in the second trimester to the mammary gland

Answer 19

tissue continues to develop with differentiation of secretory alveoli
plasma cells and lymphocytes infiltrate the nearby connective tissue

Question 20

what changes occur in the third trimester in the mammary gland

Answer 20

alveoli continue to mature with development of extensive rER

Question 21

what are changes to the mammary gland accompanied

Answer 21

reduction in the amount of connective tissue and adipose tissue present

Question 22

what happens during pregnancy in terms of hormone production

Answer 22

oestrogen and progesterone stimulate proliferation of secretory tissue and fibre fatty tissue becomes sparse

Question 23

composition of human milk

Answer 23

88% water
1.5% protein (daily lactalbumin and casein)
7% carbohydrate (daily lactose)
3.5% lipid

small amounts of ions, vitamins and IgA antibodies

Question 24

how does apocrine secretion take place

Answer 24

lipid droplets bud off from mammary acini and end up as almost vesicles with surrounding membrane

Question 25

how does merocrine secretion take place

Answer 25

proteins in milk are made rER packaged by golgi and secreted as vesicles which merge with apical membrane to release their content into the duct system

Question 26

what happens to the secretory cells of the TDLU following menopause and what happens to the connective tissue

Answer 26

secretory cells degenerate leaving one ducts

connective tissue - fewer fibroblasts and reduced collagen and elastic fibres