Reproductive System

If you decided that the organism you discovered in question 1 used parthenogenesis, what would you also know about this species

It is asexual All the individuals are female Each individual develops from an unfertilized egg

luteal phase

LH stimulation transforms the Graafian follicle into the corpus luteum, corpus lute secretes estrogen & progesterone, exert negative feedback on FSH & LH, cause endometrium to become more vascular & glandular (secretory phase of endometrium, prepare uterus for embryo implantation)

asexual reproduction

genetically identical cells are produced from a single parent cell through mitosis, single-celled organisms utilize fission, cnidarians reproduce by budding

at puberty

granolas cells secrete estrogen, triggers menarche first menstrual cycle, stimulates secondary sexual characteristics

marsupials (viviparous)

group that includes opossums & kangaroos give birth to small, fetus like offspring that are incompletely developed

sperm structure

head: contains a nucelus, capped by the acrosome, which aids in penetration of the egg. Body: consists of many mitochondria, provides energy, centriole acts as a basal body for the flagellum. Tail: consists of a flagellum, provides locomotion

hormone control

hypothalamic GnRH stimulates anterior pituitary to secrete FSH & LH, FSH stimulates the Sertoli cells to facilitate sperm development, LH stimulates the Leydig cells to secrete testosterone, controlled by negative feedback

cont luteal phase contt

if ovulated oocyte is fertilized the corpus lute is maintained by human chorionic gonadtropin (hCG), keeps high levels of estrogen & progesterone & so prevents menstruation until placenta takes over, hCG is produced by the embryo (tested foreign all pregnancy tests

amphibians

in most species fertilization is external, eggs of most species develop in water, with some interesting exceptions

fishes

in most species of bony fish fertilization is external, thousands of eggs are fertilized but only a few individuals grow to maturity, in most species of cartilaginous fish fertilization is internal (development of young is viviparous, gives birth to a few well developed offspring)

cont luteal phase

in the absence of fertilization the corpus luteum degenerates due to decreasing levels of FSH & LH, built-up endometrium is sloughed off with accompanying bleeding (menstrual phase of endometrium)

clitoris

in the absence of testosterone, the female embryo develops this & labia major

vagina

initially covered by a membrane called the hymen

female reproductive system

involves periodic release of a mature ovum (ovulation). most mammals are in heat or sexually receptive to males, only around time of ovulation this is called estrus.

ejaculation

is the ejection from the penis of about 2-5 mL of semen containing an average of 300 million sperm

different ways young develop in frogs

male carries tadpoles on his back, froglets develop in brood pouches, female carries developing larvae on her back, male holds developing froglets in his vocal pouch

sex determination

temperature-sensitive (in many fish & reptiles) Genetic (XX or XY) Humans (embryonic gonads indifferent for the first 40 days, SRY gene on Y converts gonads to testes, testosterone promotes male development)

FSH and LH are produced by

the anterior pituitary

The testicles of male mammals are suspended in the scrotum because

the optimum temperature for sperm production is less than the normal core body temperature of the organism

human menstrual cycle lasts

1 month, divided into follicular phase, ovulation, & luteal phase

Gametogenesis is requires the conclusion of meiosis II. When does this occur in females

After fertilization

birds

Amniotic egg (extraembryonic membranes, adaption for life on land) all birds practice internal fertilization, hard calcareous shell on egg, birds are endotherms (must incubate eggs to keep them warm)

reptiles

Amniotic egg (extraembryonic membranes, adaption for life on land) most oviparous reptiles lay eggs & abandon them (leathery shell on egg) other species of reptiles are ovoviviparous(forming eggs that develop into embryos within the body of the mother), some species are viviparous

Mutations that affect proteins in the acrosome would impede which of the following functions

Fertilization

Which of the following structures is the site of spermatogenesis

Seminiferous tubule

Which of the following is a major difference between spermatogenesis and oogenesis

Spermatogenesis is continuous, but oogenesis is variable.

epididymis

after the sperm are produced within the seminiferous tubules, they are delivered into a long, coiled tube called this

vas deferens

from the epididymis the sperm enter another long tube called this, which passes into the abdominal cavity via the inguinal canal

bulbourethral gland

add secretions to make up the last 10% of semen, also lubricate the tip of the penis

parthenogensis

another form of asexual reproduction, common in many species of arthropods. females produce offspring from unfertilized eggs. (females produce offspring from unfertilized eggs)

primary oocyte

at birth, a female's ovaries contain about 1 million follicles, each have this that begin meiosis but is arrested in prophase of the first meiotic division

You have discovered a new organism living in tide pools at your favorite beach. Every so often, one of the creature's appendages will break off and gradually grow into a whole new organism, identical to the first. This is an example of—

budding

granulosa cells

closely associated with the developing female gamete in the ovary

semen

complex mixture of fluids & sperm, seminal vesicles (produce a fructose-rich fluid, which makes up 60 % of semen volume)

penis

consists of erectile tissue columns (2 corpora cameos on dorsal side, 1 corpus spongiosum on ventral side, during erection these tissues fill with blood) parasympathetic nerves release nitric oxide (NO) which stimulates dilation of arteries.

prostate gland

contributes about 30% of the bulk of semen *size of a golf ball, spongy)

ovarian follicles

each follicle contains a potential egg cell called a primary oocyte & smaller granolas cells

spermatids

each of these cells undergo the second meiotic division to separate the chromatids & produce two haploids

ovulation

estrogen stimulates the anterior pituitary to secrete LH about midcycle,LH surge causes the Graafian follicle to burst, releasing its secondary ppcyte into the Fallopian tube, if oocyte is not fertilized i disintegrates, if it is fertilized it completes meiosis II, forming a mature ovum and a second polar body, fusion of the nuclei from the ovum & the sperm produces a diploid zygote

sexual arousal

external genitalia become engorged with blood

Ovarian events

follicular phase: several follicles are stimulated to grow under FSH stimulation, but only one achieves full maturity as a tertiary or graafian follicle, estrogen causes growth of the endometrium (proliferative phase of the endometrium) primary oocyte completes meiosis I (produces one large secondary oocyte & one tiny polar body)

viviparity

found in most cartilaginous fish, some amphibians, a few reptiles, & almost all mammals. The young develop within the mother & obtain nourishment directly from their mother's blood, rather than from the egg yolk. (YOUNG DEVELOP WITHIN MOTHER & OBTAIN NOURISHMENT FROM HER BLOOD)

ovoviviparity

found in some bony fish , some cartilaginous fish and many reptiles. fertilized eggs are retained within the mother to complete their development, but the embryos still obtain all of their nourishment from the egg yolk (FERTILIZED EGGS ARE KEPT WITHIN MOTHER TO COMPLETE DEVELOPMENT, YOUNG OBTAIN FOOD FROM EGG YOLK)

development of offspring 3 thing: oviparity

found in some bony fish, most reptiles, some cartilaginous fish, some amphibians, a few mammals and all birds. the eggs, after being fertilized internally, are deposited outside the mother's body to complete their development. (FERTILIZED EGGS ARE DEPOSITED OUTSIDE MOTHER'S BODY TO COMPLETE THEIR DEVELOPMENT)

monotremes

most primitive mammals, are oviparous like the reptiles from which they evolved

uterus

muscular pear shaped organ that narrows to form a neck, the cervix, which leads to the vagina

cervix

narrow opening

hermaphroditism

one individual has both testes and ovaries

polar body

one tiny daughter cell

at birth

ovaries contain about 1 million follicles, each contains a primary oocyte that is arrested in prophase of meiosis I

female reproductive system etc

ovaries develop more slowly than the testes, female embryo develops a clitoris & labia major (in the absence of testosterone, homologous structures to penis & scrotum), ovaries contain microscopic structures called ovarian follicles

In humans, fertilization occurs in the _________, and implantation of the zygote occurs in the ___________.

oviduct; uterus

most animals reproduce sexually

requires meiosis to produce haploid gametes (sperm & egg), gametes united by fertilization to produce the diploid zygote, zygote develops by mitosis into a new multicellular organism

placental (viviparous)

retain their young for a much longer period of development within the mother's uterus

folliular phase

secondary oocyte begins meiosis II, its progress is arrested in metaphase II, does not complete the second meiotic division unless it becomes fertilized in the Fallopian tube

bartholin's glands

secrete lubricant that facilitates penetration by penis

human male reproductive system

seminiferous tubules (siting of sperm production), leydig cells produce testosterone (converts indifferent external genitalia into penis & scrotum) shortly before birth, the testes descend into the scrotum b/c sperm need cooler temperature to develop, seminiferous tubules also contain supporting cells called stroll cells (nurse developing germ cells, help convert spermatids into spermatozoa (sperm) by engulfing their extra cytoplasm)

The major difference between an estrous cycle and a menstrual cycle is that

sexual receptivity occurs only around ovulation in the estrous cycle, but it can occur during any time of the menstrual cycle

male system cont

sperm are delivered into the epididymis for storage & maturation, from there sperm enter vas deferens,then to the urethra

fallopian tubes (uterine tubes or oviducts)

transport ova from the ovaries to the uterus

menstruation

unlike mammals with estrous cycles however human & ape females bleed when they shed the inner lining of their uterus

vertebrate fertilization

vertebrate sexual reproduction evolved in the ocean b$ vertebrates colonized land, marine bony fish use external fertilization (eggs & sperm are released into the water where union of free gametes occurs), Terrestrial vertebrates & some fishes use internal fertilization (sperm are introduced into the female reproductive tract)

Which of the following terms describes your first stage as a diploid organism

zygote