Fertilization

how many eggs does a women release a month from one of her ovaries into her fallopian tubes?

1

how long does an egg live after its release from the ovary?

1 day

During sexual intercourse, when a man ejaculates inside a woman's vagina, he releases about how many sperm?

300-400 million

how long can it take a fertilized egg to reach the uterus?

5-7 days

fetus

After about eight weeks of development, the embryo is called a fetus .

cilia

Hair-like projections on the cell surface used for locomotion or the movement of fluid over a cell. in this case the hairs help the egg slowly float down the fallopian tubes toward the uterus.

Menstruation

Last phase of the menstrual cycle in which the lining of the uterus along with blood and the unfertilized ovum are discharged through the vagina.

Ovulation

The process of releasing a mature ovum into the fallopian tube each month

once a sperm penetrates the outer membrane of the egg, what does the sperms head do?

When fertilization occurs, the genetic material in the sperm's head joins with the genetic material in the egg's nucleus.

acrosome

a cap-like structure on the head of a sperm cell, helps the sperm penetrate the egg.

vitro fertilization (IVF)

a process in which eggs are fertilized in a laboratory and the fertilized eggs are implanted into her uterus.

Fertilization

a union of the egg and sperm

how come women who get IVF often have twins or multiple fetuses?

bc usually, several fertilized eggs are inserted into the uterus because many of them will not successfully implant and survive. hence there is a great possibility for them to conceive twins or something

how does a sperm enter an egg?

enzymes in the acrosome of the sperm dissolve the plasma membrane and the nucleus of the sperm cell gets inside the egg

zygote

fertilized egg; an egg with a full set of chromosomes

oocyte

immature egg inside an ovary

when is a women officially pregnant?

once the fertilized egg implants in the uterine wall

what must happen for fertilization to occur?

the ovum must encounter spermatozoa during the first 12-24 hours of its passage from the infundibulum to the uterus

identical twins (monozygotic twins)

twins who develop from a single fertilized egg that splits in two embryo, creating two genetically identical organisms

fraternal twins (dizygotic twins)

twins who develop from separate fertilized eggs; they are fertilized by 2 different sperms. They are genetically no closer than brothers and sisters, but they share a fetal environment.

twins

two children born to the same mother at the same time

embryo

what a fertilized egg is called after the process of cell division begins to occur

conception

when a fertilized egg implants in the uterine wall.