Presentation on theme: "Types of Reproduction. Types of Reproduction Asexual Asexual reproduction occurs when a new organism is produced from one parent. The genetic material."— Presentation transcript:
Types of Reproduction
Types of Reproduction Asexual Asexual reproduction occurs when a new organism is produced from one parent. The genetic material of the new organism is identical to the genetic material of the parent. So the offspring and the parent have all of the same traits. Organisms that are smaller and less complex are more likely to reproduce asexually. Single-celled organisms like bacteria and protists reproduce asexually. Many plants and fungi can reproduce asexually as well. A few animals can reproduce asexually. This animation shows a cell reproducing asexually.
Asexual Types of Reproduction Budding Three types of asexual reproduction are budding, regeneration, and fission. Budding is the process when a new organism begins to form on the side of the parent and eventually breaks off. Budding is most common in plants and fungi. This picture shows a magnification of budding yeast. Hydra are part of the animal kingdom. Hydra reproduce by budding. You can see the new little hydra growing off the side of the larger, parent hydra. Picture from http://devcell.bio.uci.edu/images/Hydra.jpg.
Asexual Types of Reproduction Regeneration Regeneration is the ability to restore lost or damaged tissues, organs, or limbs. It is most common in animals that do not have a backbone like worms and starfish. Sometimes, if an organism loses a limb or if the organism is split into two parts, both parts will regenerate the missing pieces, creating two organisms from one. Planaria regeneration. In the final picture, two planaria worms are formed. Picture retrieved from http://www.ub.edu/planaria/ January 20, 2010.http://www.ub.edu/planaria/
Asexual Types of Reproduction Binary Fission Binary fission occurs when a single celled organism splits into two cells. Bacteria and protists reproduce by binary fission. First the parent cell makes a copy of its genetic material (the green, squiggly circle), then the cell membrane pinches in and two new daughter cells split apart. Because the cell copied its genetic material, the two cells have the same traits.
Types of Reproduction Sexual Sexual Reproduction requires two parents. The female parent provides an egg cell, and the male parent provides a sperm cell. The egg cell and the sperm cell combine to form a new individual. The egg cell has genetic material from the female parent and the sperm cell has genetic material from the male parent. Therefore, the offspring will have genetic material from both parents. This is called genetic variation. Sexual reproduction allows new individuals to have genetic variation because they get a mix of traits from two parents. Egg cell Sperm cell New individual
Sexual Types of Reproduction Plants - Pollination Pollination is a form of sexual reproduction. Pollination occurs in plants. Pollen is taken from the male parts of one plant and delivered to the female parts of another plant, usually by an insect. The pollen then travels inside the flower and fertilizes an egg. The egg will grow into a seed which can become a new plant. Pollination also allows for genetic variation because the traits from two plants are mixed.
In animals, sexual reproduction encompasses the fusion of two distinct gametes to form a zygote. Gametes are produced by a type of cell division called meiosis. The gametes are sex cells that contain only one set of chromosomes, while the zygote has two sets of chromosomes. In most cases, the male gamete, called sperm, is mobile and has a flagellum. The female gamete, the egg, isNot mobile and is large compared to the male gamete. Sexual Reproduction in Animals
There are two mechanisms by which fertilization can take Place. The first is external (eggs fertilized outside of the body) The second is internal (eggs fertilized within the female reproductive tract. Sexual Reproduction in Animals
Types of Reproduction Sexual vs. Asexual Take a look at the table below. It summarizes the important differences between sexual and asexual reproduction. Sexual Reproduction Asexual Reproduction Number of Parents 2 parents1 parent Genetic Variation Lots of genetic variation (a mix of traits from 2 parents) No genetic variation (the same traits from only 1 parent)
Sexual Versus Asexual Reproduction What are the advantages of sexual reproduction? What are the advantages of asexual reproduction?