ANS2140 Exam 4, ISU ANS 2140 Exam 4 ( Reproductive System and Mammary System )

fetal mammogenesis

growth of primary ducts, regulated by GH

prepubertal mammogenesis

isometric/allometric growth, regulated by GH, E2, and glucocorticoids

puberty mammogenesis

secondary branching of ducts, regulated by E2

Pregnancy mammogenesis

lobular and alveolar growth of mammary glands, regulated by E2, P4, PRL, GH, and ACTH.

Lactation

milk is secreted by alveoli, regulated by PRL

involution

gradual return to normal state regulated by galactopoetic hormone changes.

GnRH (spermatogenesis)

released by hypothalamus, stimulates anterior pituitary to release FSH and LH, inhibited by inhibin

FSH

released by anterior pituitary, stimulates the sustentacular cells to release androgen binding hormones, inhibited by amount of sperm

LH

released by anterior pituitary, stimulates interstitial endocrine cells to release testosterone, inhibited by reduction of GnRH

Androgen binding hormone

released by sustentacular cells, binds to testosterone to focus it in the seminiferous tubules

Testosterone

released by interstitial endocrine cells, stimulates sertoli cells to create and maturate sperm cells

Fibroelastic Penis

increased amounts of collagen, during erection the penis extends out of the body, and there is decreased blood flow (Boar and Bull)

Vascular Penis

Decreased amounts of collagen, increased blood flow during erection ( Stallions, Dogs, Humans )

Glans Penis

end of the penis that senses temperature and pressure within the female

Scrotum

skin that surrounds the testicle

Testes or Testicle

spermatogenesis occurs here

Epididymis

where sperm matures and is stored

Vas deferens

during ejaculation, sperm are transported here, seminal plasma is also made here and turns sperm into semen as it is traveling through

Sigmoid Flexure and retractor penis muscle

retracts penis into body cavity when it is not erect

Sustentacular cells

cells that help with the maturation of sperm and have receptors for FSH and Testosterone on them ( start in interstitial space and move towards the lumen of the seminiferous tubules)

Interstitial endocrine cells

cells that produce testosterone and are in the interstitial spaces containing receptors of LH and the production of Testosterone is stimulated by LH

Acrosome

organelle containing enzymes important for fertilizing an egg/penetrating egg(oocyte)

Seminiferous tubules

1000s of tubules that are open-ended, up to 3 miles of tubule and this is where sperm is made

Rete Testis

100s of tubules and are the collection point of sperm

Efferent Ductile

6-12 tubules, sperm moves here, fluid will be absorbed, and will funnel sperm into the epididymis

Spermatic Cord

allows for testes to be raised and lowered depending on temperature

Pampiniform Plexus

counter-current mechanism, use mechanism to dissipate heat from arteries allowing for a gradient of temperatures (39 degrees C to 35 degrees C - 2-4 degree difference between testicles and body temp)

Head

contains nuclear (DNA) material and the acrosome

Mid piece

contains mitochondria ( Metabolic region of the Sperm)

Tail

used for movement, only active inside of the female

Seminal Vesicles

produce viscous alkaline fluid that neutralizes acidity in the vagina, 70% of semen, contains fructose, ascorbic acid coagulating enzyme and prostaglandins

Fructose

energy source

Prostaglandin

decreases viscosity in the vagina, capacitation of sperm, and stimulates reverse peristalsis of vagina

Ascorbic Acid Coagulating Enzyme

reduce vaginal acidity

Prostate Gland

milky, slightly acidic, fluid production that contains citrate and enzymes that aid sperm in capacitation ( activation )

Bulbourethral Gland

secretes thick, clear, mucus prior to ejaculation to lubricate the glans penis and neutralize acidity from urine

Ovary

site of gametogenesis/oogenesis and the site of follicular development

Oviduct

travels down this once released from ovary, contains the site of fertilization where the sperm and oocyte meet

Uterus

help transport sperm when released into, site of preparation of sperm for fertilization and fetal development

Cervix

barrier for sperm, lots of folds here where sperm get lost, during pregnancy it created a mucosal plug to prevent bacteria from entering, and it serves as storage/reservoir for sperm

Immunoprivilaged

space where immune system is dampened keeping our body from recognizing something as foreign such as a baby

Vagina

copulatory organ, provides temperature, and pressure for glans penis, birth canal, site of semen deposition, slightly acidic as a barrier for bacterial growth, secretions for lubrication from the cervix

Sub urethral Diverticulum

where the ureters meet with the vagina allowing the release of urine

Vulva

the external genitalia of a female

Infundibulum

funnel, helps catch the oocyte

Ampulla

first half of the oviduct, not very muscular, important for movement of oocyte for fertilization, has a larger diameter

Isthmus

smaller diameter, more muscular, after fertilization, nourish the sperm and oocyte (zygote)

Ampullary Isthmic Junction

site of fertilization

Utero tubal junction

where the uterus and uterine horns meet, helps with the development of embryo, and blocks poly spermy

Germinal Epithelial Layer

ruptures during ovulation

Cortex

contains female gametes, follicles, and estrogen production, development of the corpus luteum

Medulla

what is needed to support oogenesis, nerves, blood vessels, lymphatic system, and connective tissue

Antral

fluid filled spaces between granulosa cells

Zona Pellucida

layer around oocyte to protect oocyte from invaders

Corona Radiata

radiant crown that surrounds oocyte as it is ovulated

Isometric growth

body and mammary gland grow at the same rate ( connective tissue growth )

Allometric growth

period of growth where the mammary system grows at a rate slower than the body ( greater ductile growth )

Involution

process where the body resets itself back to its original/ normal state

Mammogenesis

development of the mammary gland that starts at embryonic development all the way through pregnancy with 4 defined stages Fetal, Prepubertal, Pubertal, and Pregnancy/Lactation

Fetal Mammogenesis

driven/regulated by growth hormone, about 30 days gestation there is a doubling of cells supporting sprout development

Primary Sprout

forms gland cistern, teat cistern, and teat canal as all solid masses not canals yet

Secondary Sprout

forms major ducts

Canalization

around day 100 of gestation there is formation of the lumen

Prepubertal Mammogenesis

Regulated by GH, Estrogen and Glucocorticoids and is the development of fat pads, connective tissue, and the primary ducts some Isometric growth at this time

Pubertal Mammogenesis

ductile growth and branching of the ducts including secondary branching and is regulated by estrogen

Pregnancy Mammogenesis

Lobular growth that is driven by estrogen, progesterone, PRL, GH, ACTH

Lactogenesis

production of milk including colostrum, foremilk, and hindmilk

Colostrum

first 48 hours of milk production and it is poor in fat and high in protein

Milk

changes over the lactation cycle to meet the offsprings nutritional requirements

Alveolar Secretory Epithelial Cells

polarized cells that have different functions for each part of the cell and they are the milk producing cells

Milk Water

greatest component of milk and makes up around 88% of cow milk

Milk Lactose

is the primary carbohydrate in milk and is the least variable component, it is slowly absorbed in the GIT and when broken down we can get lactic acid which lowers pH increasing and promoting calcium absorption

Milk Fat

most variable component, is a good source of energy but is not readily variable, helps to add a fat layer to offspring to help with insulation, 95% is diacylglycerides , cholesterol, and non esterified fatty acids

Milk Protein

unique to milk, containing all essential amino acids consisting of When and Casein

Whey

20% and fast absorption

Casein

80% and slow absorption

Galactokinesis

milk let down/ expulsion of milk from alveoli regulated/ controlled by oxytocin, where the suckling will primarily cause the release of oxytocin

Galactopoiesis

maintenance of lactation keeping the lactation curve moving forward without it there would be a cease in production, regulated by PRL and PRL surges with suckling

Sperm cell that results from spermatogenesis

spermatozoa

develops from golgi apparatus

head

develops from cytoplasm

mid piece

develops from centriol

tail

cells that nurture spermatagonia

sustentacular cells

sperm cell that results from meiosis II

spermatid

egg released from ovary post ovulation

Oocyte

Cell division that produces 4 genetically different haploid daughter cells

meiosis

hormone that sustains pregnancy if fertilization succeeds

progesterone

cell divions that produces 2 genetically idental diploid daughter cells

mitosis

hormone that peaks before ovulation

estrogen

final stage of menstrual cycle, stimulated by LH, to keep uterine lining thick

secretory phase

phase where progesterone increases and formation of corpus luteum

luteal phase

phase where estrogen increases and follicles develop

follicular phase

Spermatogonia undergo mitotic division and produce primary spermatocytes

Proliferation (1st step of spermatogenesis)

length of proliferation

16 days

primary diploid spermatocytes undergo meiosis I, forming haploid seconday spermatocytes

2nd step of spermatogenesis

length of 2nd step of spermatogenesis

12 days

secondary spermatocytes undergo meiosis II, creating spermatids, reducing chromosome number

3rd step of spermatogenesis

length of 3rd step of spermatogenesis

12 days

spermatid matures to become spermatozoa

spermiogenesis (4th/final step of spermatogenesis)

length of spermiogenesis (4th/final step of spermatogenesis)

24 days