reproductive review Flashcards
study for test quiz, etc
main function of reproductive system
A collection of organs that allow an organism to make more of its species.
Ovary def.
The reproductive organ that produces eggs and hormones.
Fallopian Tube def.
The tube that leads from an ovary to the uterus.
Uterus def.
The organ in the female reproductive system where a zygote / baby grows and develops.
Vagina def.
The passageway in the female reproductive system that receives sperm from a male or
the canal the unfertilized egg / baby comes out of.
Cervix
The narrow neck-like passage forming the lower end of the uterus.
Order of egg flow
Ovary—Fallopian Tube——–Uterus——-Vagina
Explain egg production in women:
Women have all the eggs they’ll ever have when they are born. They have many eggs that are all at different stages of development and release usually only one egg a month.
testes def.
The reproductive organ that produces sperm and hormones.
epididymis def.
Sperm matures and is stored in the epididymis.
Vas Deferens def
A tube in males where sperm leaves the epididymis and mixes with fluids to make semen.
Urethra def
The tube through which semen leave the body.
Penis def.
The male reproductive organ that transfers semen into the female’s body.
what is the order of sperm flow?
testes—-epididymis——-vas deferens——–urethra
Explain why the testes hang outside the male body in the scrotum:
sperm cannot develop at the average body temperature of 37°C.
Therefore, the 2 testes rest within the scrotum (a skin-covered sac that hangs outside the body). The scrotum allows the testes to be about 2 degrees cooler than if they rested inside the body.
zygote def.
A fertilized egg.
Meiosis
Cell division that produces sex cells.
Gametes def.
Sex cells (egg and sperm).
How many chromosomes do human body cells have?
46
How many chromosomes do human sex cells have (egg or sperm)?
23
Why is it important that sex cells have ½ the DNA of body cells?
For HUMANS = egg and sperm both have only 23 chromosomes in them, which is 1/2 the normal amount of 46 chromosomes that are in human dna. By having only 23 chromosomes each, when the egg and sperm join to make a zygote, they will end up with the correct 46 number of chromosomes.
Fraternal Twins summary
The mother releases 2 eggs, simultaneously, and both eggs are fertilized by separate sperm. Share 50% of their DNA – Formed from 2 eggs and 2 sperm.
Identical Twins summary
A single zygote divides within 4-8 days after egg fertilization. It splits into 2 identical genetic halves. Share 100% of their DNA – Formed from 1 egg and 1 sperm. The one egg is fertilized by one sperm and then splits.
Conjoined Twins summary
Identical twins which fail to completely separate within the 4-8 day time period after fertilization. The zygote tries to split after 12 days and can’t completely separate anymore. Share 100% of their DNA – Formed from 1 egg and 1 sperm. The one egg is fertilized by one sperm and then attempts to split, but doesn’t split all the way and stay conjoined.
