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What is gamete

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					An embryo is an animal in the early stages of growth from an egg       What is a gamete ?
cell which is the result of the union of a female gamete with a male
gamete

A gamete is a mature male or female germ cell usually possessing a What is the name of the male gamete ?
haploid chromosome set

A sperm cell is a male gamete                                          What is the name of the female gamete ?


The ovum is the female gamete                                          What is fertilisation ?


The fertilisation is the process of union of two gametes whereby the How could be fertilisation prevented ?
somatic chromosome number is restored and the development of a
new individual is initiated

Birth control prevents conception or pregnancy                         Which devices prevent conception ?


Condoms, diaphragms and pills can prevent conception                   What is a condom ?

A condom is a sheath commonly of rubber worn over the penis            What is a diaphragm ?


A diaphragm is a molded cap usually of thin rubber fitted over the What is the cervix ?
uterine cervix to act as a mechanical contraceptive barrier

The cervix is the narrow outer end of the uterus producing mucus       What is a pill ?


A pill is any of various preparations that usually contain a What is a morning after pill ?
combination of a progesterone and an estrogen which are taken
orally especially on a daily basis, and act as contraceptives typically
preventing ovulation by suppressing secretion of gonadotropins (as
luteinizing hormone) or preventing endometrium development or
cervix mucus fluidity

A morning after pill is an oral drug usually containing high doses of What is an IUD
estrogen taken up to usually three days after unprotected sexual
intercourse that interferes with pregnancy by inhibiting ovulation or
by blocking implantation of a fertilized egg in the human uterus

IUD stands for intrauterine device which is a device inserted into     What is pregnancy ?
and left in the uterus to prevent effective pregnancy

Pregnancy is gestation : the carrying embryos in the uterus            How can pregnancy be detected ?


Pregnancy can be known thanks to a test based on the detection of What does HCG stands for ?
HCG produced by the trophoblast which is a part of the blastocyst

HCG stands for human chorionic gonadotropin                            How could infertile couples be helped ?
Infertile couples may be helped thanks to Assisted procreation         What does IVF stand for ?
which includes techniques such as IVF; ICSI, ZIFT, surrogacy

IVF stands for in vitro fertilization                                  What does ICSI stand for ?


ICSI stands for intracytoplasmic sperm injection                       What does ZIFT stand for ?


ZIFT stands for zygote intra fallopian transfer                        What is a surrogate mother ?


A surrogate mother lets her womb                                       What is a womb ?


A womb is a uterus                                                     What is a uterus ?


A uterus is the muscular organ of the female mammal for containing What is a Fallopian tube ?
and usually for nourishing the young during development prior to
birth

A Fallopian tube is either of the pair of tubes that carry the egg from What is an ovary ?
the ovary to the uterus

An ovary is the female gonad producing gametes and sexual              What are estrogens ?
hormones : estrogens and progesterone

Estrogens are any of various natural steroids (as estradiol) that are What is progesterone ?
secreted chiefly by the ovaries, placenta, and that stimulate the
development of female secondary sex characteristics and promote
the growth of the endometrium

Progesterone is the female steroid sex hormone that is secreted by What is corpus luteum ?
the corpus luteum to prepare the endometrium for implantation and
later by the placenta during pregnancy to prevent rejection of the
developing embryo or fetus;

A corpus luteum is a yellowish mass of progesterone-secreting          What is a follicle ?
endocrine tissue that forms immediately after ovulation from the
ruptured graafian follicle in the mammalian ovary

A follicle is a vesicle in the mammalian ovary that contains a What is an oocyte ?
developing oocyte surrounded by a covering of cells


An oocyte is a female non mature gamete                                Which hormone stimulates follicle
                                                                       maturation ?

FSH stimulates the follicles growth                                    What does FSH stand for ?


FSH stands for follicle-stimulating hormone                            What is ovulation ?
Ovulation is the discharge of a mature ovum from the ovary               Which hormone stimulates ovulation ?


LH stimulates ovulation                                                  What does LH stand for ?


LH stands for luteinizing hormone                                        What are the different functions of LH ?


LH stimulates ovulation, corpus luteum development and What are Leydig cells ?
progesterone secretion, and Leydig cells production of testosterone

Leydig cells belong to the interstitial tissue inside the testis which   What is testosterone ?
produces testosterone

Testosterone is a hormone produced especially by the testes and that What are the testes ?
is responsible for inducing and maintaining male secondary sex
characters

The testes are the male gonads                                           What is a gonad ?


A gonad is a reproductive gland (as an ovary or testis) that produces When are gonads active ?
gametes

Gonads become active after puberty ?                                     What is puberty ?

Puberty is the period of becoming first capable of reproducing What is menstruation ?
sexually marked by maturing of the genital organs, development of
secondary sex characteristics, and in the human and in higher
primates by the first occurrence of menstruation in the female

Menstruation is a discharging of blood, secretions, and tissue debris What is a menstrual cycle ?
from the uterus that occurs at approximately monthly intervals

The menstrual cycle is the cycle of physiological changes in the         Which organs control the menstrual
endometrium from the beginning of one menstrual period to the            cycle ?
beginning of the next

Ovaries control the menstrual cycle thanks to their hormones             What is the ovarian cycle ?
secreted during the ovarian cycle

The ovarian cycle is the periodical modifications of the ovaries : Which organ controls the ovarian cycle
development of follicles, ovulation, development and disappearance ?
of corpus luteum

The pituitary gland controls the ovarian cycle thanks to FSH and         What is the pituitary gland ?
LH

The pituitary gland is a gland connected to the hypothalamus and         What is the hypothalamus ?
producing LH and FSH

The hypothalamus is a nervous tissue connected to the pituitary What does GnRH stand for ?
gland and producing GnRH
GnRH stands for gonadotropin-releasing hormone                        What is the function of GnRH ?


GnRH stimulates the production of LH by the pituitary gland ?         Is there any control on the hypothalamus
                                                                      and the pituitary gland ?

There are positive feed-back and negative feed-back from sexual       What is a negative feed back ?
hormones on hypothalamus and pituitary gland

A negative feed back is a in return control that tends to dampen a    What is a positive feed back ?
process by applying the output against the initial conditions for
example testosterone or low quantity of estrogens or progesterone
on the production of GnRH and LH

A positive feed back is a in return control that tends to magnify a   What is the consequence of a large
process for example a high quantity of estrogens induces a large      discharge of LH ?
discharge of LH

A large discharge of LH induces ovulation                             After ovulation, fertilisation may occur
                                                                      followed by nidation, what is the
                                                                      process of termination of a beginning
                                                                      pregnancy ?

Abortion is the process of termination of a pregnancy closely What is an embryo ?
followed by the death of the embryo

				
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posted:8/28/2011
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