OSMOREGULATION / FEMALE GENITAL Flashcards
what is the core principle of osmoregulation
concentraton gradients across permeable membranes tend to diminish overtime via movement of water and other solutes (salts and other dissolved molecules)
define hyperosmotic
if the solute concentration in the blood is higher than in sorrounding water
water seeps into body and solutes leak out of the body
define hyposmotic
if the solute concentration in the blood is lower than in sorrounding water
water seeps out of the body and solute leaks into the body
define isosmotic
if the solute concentration is the same as the surrounding water
water and solute concentration do nothing
how do the water and solutes move
water moves according to the total solute concentration and solutes move according to the their individual concentratins
what are isosmotic vertebrates called
osmoconformers
how do isosmotic vertebrates work
simple
cocentration of solutes in body fluid is similar to that in salt water
requires that the body opperate with high solute levels
explain hagfish as isosmotic verts
they have high levels of sodium and other ions
short nephric tubules
explain chondrichthyans and coelacanths as isosmotic verts
high concentrations of urea (and other nitrogenous substances) retained in the blood
osmotic concentration of the body is increased without salts
urea tends to leak out of the body, and salts tend to leak in, but there is NO NET MOVEMENT OF WATER
osmoregulation in most salt water fish
simple
body is hyposmotic to the environment
salts diffuse into body and water seeps out
what type of kidneys do salt water fish have for hyposmotic regulation
aglomerular kidnets
define aglomerular kidneys
lack glomeruli, bowmanns capsules. and distal parts of the nephric tubules (whhere the salt resorption occurs)
less filtrate enters the uriniferous tubules so urine w high solute is formed by the secretions into the tubules
what do acessory structures do in hyposmotic salt water fish
help remove salt from the body in some marine fish and tetrapods
ex. gills and specific glands
osmoregulation in fresh water fish
simple
hyperosmotic to environment
water seeps into tissues and salts leak otu
how does osmoregulation work in hyperosmotic freshwater fish
large quantities of fluid pass from glomeruli to bowmans capsules
distal parts of tubules are well developed
lots of dilute urine produced
why is the urine very dilute in fresh water fish
kidneys are primarily for water elimination rather than excretion
osmoregulation on land simple
evaporation can lead to dehydration
3 groups
lissamplbians
reptiles
mammals
explain lissamphibian osmoregulation on land
storage of urea, excretion in the water
explain reptile osmoregulation on land
uric acid secretion with minimal water loss
explain mammal osmoregulation on land
excretion of urea in concentrated urine because of LOH
explain how LOH makes cocnentration urine in land mammals osmoregulation
sodium is actively pumped into the interstitial space around the loop of henle
hypermosmotic conditions establish outside the uriniferous tubules
water trains out of the uriniferous tubules by osmosis, leaves very conc urine
what is urinary bladder simple
sac for storing urine that can expand/swell
where is urine stored in most fish
in expanded ends of the urinary ducts that empty into the cloaca — cloaca is not a real urinary bladder
where is urine stored in most tetrapods
in a true urinary bladder which develops as an outpouch of the cloaca
how does urine flow in a tetrapod
urine goes from urinary ducts, through cloaca, into bladder, then out from bladder using cloaca
where is urine stored in therian mammals
bladder
how does urine flow in a therian mammal
ureter, bladder, urethra, out
where is urine stored in reptiles and birds
lbladder is lost, it the urine or uric acid si stored in the cloaca until expulsion
what is the most common type of repreoduction
sexual
only a few lizards are parthenogenic
what does genital system consist of
gonas (testes/ovaries) and ducts which produce gametes and hormones
when does genital system appear in development
very late and the early gonads are indifferent
how do paired gonads arise
from the genital ridge (a thickening of the splanchic mesoderm) , which then extends along the body medial to the nephric ridge, protruding down tot he coelem
what are the primary sex cords
epithelium that covers the gonads
the PGC travel from yolk sac to sex cords
what are the primordial germ cells
undifferntialed stem cell that will become wither spermazoa or oocyte
are ovaries usually paired of single
usually paired BUT
1 median ovary in cyclostomes and some teleosts
1 functional ovary in most birds, some chondrichtyans and non avian reptiles and mammals
how are the ovaries bound to the body wall
by mesentary called the mesovarium
where do ova form
ova (eggs) form in the follicles on the outer part of the ovary
what is another name for oviducts
mullerian ducts
what is the ostium
duct entrance
flares into the infundibulum and margians the finbriae to embrace the ovary
how does ova enter the ostium from the ovary
using cilia on the infundibulum to help move the egg through the ostium into the oviduct
pathway for ova
infundibulum
ostium
ovary
what is uterus
expansion of the posterior end of the ovidcut and it stores eggs and houses developing embryo
what muscle is on uterus wall
smooth
what is shell gland
special region of oviduct that adds external coat to ovum after fertilzation
in reptiles the coat contains albuen (egg whiye), shell membrane and a calcareous or leathery shell
what type of fertil. would u find shell gland in
internal because it would block sperm for external
female genital system in cyclostomes (non bony fish)
simple
external fertilzation
eggs shed into the coelem then exit the body through either cloaca (hagfish) or genital pres lamprey)
how many eggs lamprey produce and what type of fisha re they
over 200k
non bony fish
female genital system in condrichthyans (non biny fish)
internal fert
eggs pass through infundibulum to the shell gland, then the isthmus to the uterus
in ovuparous - shell gland adds albumen and egg case
in vivaparous - yolk sac might form placaenta or the crnivourus
oviparous
uses eggs
viviaporous
birth to live young
what fert in female genital system of bony fish
external fertilization - the unfert eggs exit through genital pores, seprate from the anus
female gential in non teleost (bony fish)
oviduct transports the eggs to the exterior
female genital in teleost (bony fish)
most
oviduc rgeresses and new short ovarian duct forms fromt he infolding genital ridge, continuous with the lumen of the ovary
female genital system reptiles and lissamphib
(tetrapods)
oviduct transports eggs to exterior (internal fert except in anurans)
viviparity in a few caecilians, lissamph or squatmes
caecilians that are vivaparous may have secretion that nourish fetus
shell gland prominent in most reptiles, uterus may be expended or inditinct
female genital in monotremes (playpus or echindnas)
tetrapod
oviparous - small leathery eggs
cloaca partly divided into anus and urogenitual sinus
female genital in marsupials (opossums and kangaroos)
tetrapod
two uteri - one per ovidcut
cloaca present but is more preominently divded thn in monotremes
