mammary physiology

Question 1

_______ function to keep milk in udder and bacteria out of udder. Its distal end is closed by the _________, which ____ during milking, allowing the orifice to _______

Answer 1

Streak canals; teat sphincter; relaxes; open

Question 2

Canal patency ______ and streak canal length ____ with lactation

Answer 2

decreases, increases

Question 3

a ____ forms during a dry period to help seal the canal.

Answer 3

keratin plug

Question 4

____ are designed to minimize the chance of bacteria entering the gland because the ______ remains open for one hour or more after milking.

Answer 4

teat dips; streak canal

Question 5

The ____ is separated from the streak canal by folds of tissue called the ____, which prevents milk leakage when the udder is full and is the entry point of ____. The capacity of this appendage is ____ mL.

Answer 5

teat cistern; Furstenberg’s rosette; leukocytes; 30-45

Question 6

The collecting area for the mammary ducts is the _____, which contains a capacity of up to ____ mL of milk.

Answer 6

gland cistern; 400

Question 7

The _______ marks the boundary between the teat cistern and the gland cistern

Answer 7

cricoid fold

Question 8

_____ are located at the proximal end of the teat cistern

Answer 8

cricoid rings

Question 9

_______ branch from the gland cistern

Answer 9

mammary ducts

Question 10

_________, which are essential to milk production, form a barrier to the passage of substances from the blood to the lumen. They line the _______ and are attached to the _____.

Answer 10

Alveolar epithelial cells; alveolar lumen; basement membrane

Question 11

________ make up the lining surrounded by contractile cells. They contract in response to the presence of ______ and squeeze milk out of the alveolar lumen and into small ducts. They make up an __________ of cells, meaning the stimulation of one cell does not cause contraction of all cells nearby.

Answer 11

alveolar myoepithelial cells; oxytocin; incomplete syncytium

Question 12

______ bring milk building blocks to alveoli and remove waste products

Answer 12

capillaries

Question 13

______ are associated with contraction of blood vessels and not with milk ejection

Answer 13

smooth alveolar muscle fibers

Question 14

size and shape of cellular __ vary throughout milk production, and they position themselves at the base of the cell due to their ____

Answer 14

nuclei; polarity

Question 15

____ increase in number per alveolar cells after parturition

Answer 15

mitochondria

Question 16

_____ are the site of protein synthesis for retention in cell or export

Answer 16

ribosomes

Question 17

____ is the the site of lactose synthesis and protein packaging. This organelle also hypertrophies during ______

Answer 17

Golgi Apparatus; lactogenesis

Question 18

_____ originate in the Golgi apparatus to carry non-fat constituents and vesicular membranes to the apical membrane

Answer 18

secretory vesicles

Question 19

____ are vesicles with enzymes that detoxify various compounds in the cell

Answer 19

peroxisomes

Question 20

__ are active during involution or mastitis-related cell damage

Answer 20

lysosomes

Question 21

_____ is the fluid matrix of the secretory cell and the site of anaerobic breakdown of ______

Answer 21

cytoplasm; glucose

Question 22

___ are hollow tubes of protein tubulin that are important in cell division and are located in the _______

Answer 22

Microtubules; cytoskeleton

Question 23

____ are located around the apical portion of the cell, joining adjacent cells and forming tight barriers which stop the passage of material between cells

Answer 23

tight junctions

Question 24

___ join adjacent cells and allow materials of low molecular weight to move between cells

Answer 24

gap junctions

Question 25

the ______ is a thin layer of acellular proteins from connective tissue cells in the ______, composed of ____ as well as type IV collage, laminin, heparin, and sulfate proteoglycans. It modulates ____ and _____

Answer 25

Extracellular Matrix; parenchyma; basal lamina; cell shape; gene expression

Question 26

Milk precursors are taken from the blood into secretory cells through ______ and ____ membranes

Answer 26

basal; lateral

Question 27

milk is discharged through this into the lumen

Answer 27

apical membrane

Question 28

milk precursors come from the bloods through this, which is located in the interstitial space below the secretory cell

Answer 28

basement membrane

Question 29

the ____ presents during fetal life around day 40

Answer 29

mammary gland

Question 30

the horse has a _____ teat:gland ratio

Answer 30

1:2

Question 31

___ is the excessive or inappropriate production of milk

Answer 31

galactorrhea

Question 32

____ is the enlargement of a man's breasts, usually due to hormone imbalance or hormone therapy

Answer 32

gynecomastia

Question 33

the ___ is the ductular and secretory tissue

Answer 33

parenchyma

Question 34

the __ is the connective and supporting tissue of an organ

Answer 34

stroma

Question 35

the __ are secretory epithelial cells, organized into lobules and lobes

Answer 35

alveoli

Question 36

duct systems are lined by ...

Answer 36

epithelial cells

Question 37

the mammary support system is made up of the __ suspensory ligament, ____, _____ suspensory ligament, and fine connective membranes

Answer 37

lateral, pelvis, medial

Question 38

the 2 lateral suspensory ligaments are the ___ and ______, and are (inflexible/flexible). they arise from the ____ tendon

Answer 38

superficial; deep; flexible; subpelvic

Question 39

the ____ arises from the abdominal wall and is composed of two adjacent heavy yellow elastic sheets of tissue that respond to the weight of the udder, forming an __________.

Answer 39

median suspensory ligament; intermammary groove

Question 40

deep lateral suspensory ligaments are anchored by projections called _____

Answer 40

lamellae

Question 41

the teat is aka the _____

Answer 41

papilla mammae

Question 42

the skin of the teat is made up of ________ epithelial cells

Answer 42

stratified squamous

Question 43

The correlation between mammary gland weight and milk yield is

Answer 43

positive

Question 44

the primary source of support for holding the udder of the cow in place is the

Answer 44

median suspensory ligament

Question 45

lateral suspensory ligaments are made up mostly of _______ tissue

Answer 45

fibrous connective

Question 46

blood flow to the mammary gland requires ___ units of blood to pass through the gland to synthesize 1 unit of milk

Answer 46

400

Question 47

alveoli in the mammary gland of cattle are first formed during _____

Answer 47

pregnancy

Question 48

severing of the roots of all of the nerves supplying the mammary gland would reduce sensation, destroy ___ innervation, and eliminate neural control of ___ of the arterioles in the mammary gland

Answer 48

sympathetic; vasodilation

Question 49

milk flow through the streak canal is influenced by the _____ muscle of the teat

Answer 49

sphincter

Question 50

the alveolus contains how many layers of secretory epithelial cells?

Answer 50

1

Question 51

the germinal layer that gives rise to the mammary stroma is the ______

Answer 51

mesoderm

Question 52

mammary epithelial cells are derived from the ____derm, ___ cells, cells of the ______, and the germinal layer of the _______

Answer 52

ecto, cap, mammary, epithelium

Question 53

___ of the terminal end bud in rodent mammary glands are stem cells that give rise to other cells

Answer 53

cap cells

Question 54

extended periods of allometric growth of the mammary gland occurs during ____, ____, and ____ stages

Answer 54

postnatal; pregnancy; lactation