So, bacteria can’t reproduce sexually, but they can exchange genetic information with each other. Using a pilus, two bacteria make contact with each other and exchange genetic material. This is called conjugation. Some bacteria simply take up DNA which is floating around in their environment.

Prokaryotic cells can reproduce asexually only through binary fission. Binary fission is the process by which a bacterial cell splits into two identical daughter cells. This is a very fast process and contributes to the rapid growth and replication of bacteria.

Prokaryotic cells are those cells that are not enclosed in a membrane or an envelope. Reproduction in the case of prokaryotes maybe both sexual and asexual depending upon organisms and their mechanism. Some of the methods by which asexual reproduction results in offsprings are fragmentation, budding, and fission.

Zygotes and their resulting sporophytes are diploid. Mosses can reproduce sexually or asexually. Moss sperm-release needs the rain, but spore-release needs it to not be raining. The sporophyte is nourished at least partially by the gametophyte.

There are two types of reproduction: asexual and sexual reproduction.

Organisms that reproduce through asexual reproduction tend to grow in number exponentially. Many organisms can reproduce sexually as well as asexually. Aphids, slime molds, sea anemones, some species of starfish (by fragmentation), and many plants are examples.

Animal Reproduction In asexual reproduction, an individual can reproduce without involvement with another individual of that species. The division of a bacterial cell into two daughter cells is an example of asexual reproduction.

There are several different methods of asexual reproduction. They include binary fission, fragmentation, and budding. Binary fission occurs when a parent cell splits into two identical daughter cells of the same size.

Sperm develop in the testicles within a system of tiny tubes called the seminiferous tubules. At birth, these tubules contain simple round cells. During puberty, testosterone and other hormones cause these cells to transform into sperm cells.

There are three tubes inside the penis. One is called the urethra. It is hollow and carries urine from the bladder through the penis to the outside. The semen travels through the urethra and comes out the end of your penis.

In fact, women have three portals: a urethra, vagina, and anus.

MYTH: You can hold in your period You cannot hold in your period. Pee and period blood do not exit the body from the same place – urine exits from the urethra which has sphincters so can be controlled while period blood exits from the vagina which does not have sphincters so cannot be controlled.

When the baby is ready for birth, its head presses on the cervix, which begins to relax and widen to get ready for the baby to pass into and through the vagina. Mucus has formed a plug in the cervix, which now loosesn. It and amniotic fluid come out through the vagina when the mother’s water breaks.

If “hole” can be defined purely as an opening, then perhaps a straw does have two holes. If a hole is defined mathematically, like a torus shape, then a straw has one hole.

So for any shape that is topologically a sphere, its Euler number is 2; for a donut-like torus, it’s 0; for a flat disk it’s 1; and so on. Each surface has its own Euler number. A hollow torus can be cut twice — once around the tube and then along the resulting cylinder — so by this definition, it has two holes.