This is caused by mitosis, in which a cell divides into the same diploid cell, having the exact same characteristics and chromosomes just like the parent cell. What kind of cell division occurs during the asexual reproduction of a unicellular organism?
Nam D. Apr 13, I would say mitosis. Multiple fission is more often observed among protists. Starfish reproduce by fragmentation and yeasts reproduce by budding. Both are types of asexual reproduction. Asexual reproduction can be very rapid. This is an advantage for many organisms. It allows them to crowd out other organisms that reproduce more slowly. Bacteria, for example, may divide several times per hour. Under ideal conditions, bacteria can divide to produce millions of bacterial cells in just a few hours!
However, most bacteria do not live under ideal conditions. If they did, the entire surface of the planet would soon be covered with them. Instead, their reproduction is kept in check by limited resources, predators, and their own wastes. This is true of most other organisms as well. Sexual reproduction involves two parents. As you can see from Figure below , in sexual reproduction, parents produce reproductive cells—called gametes —that unite to form an offspring.
Gametes are haploid cells. This means they contain only half the number ofchromosomes found in other cells of the organism. Gametes are produced by a type of cell division called meiosis , which is described in detail in a subsequent concept. The process in which two gametes unite is called fertilization. The fertilized cell that results is referred to as a zygote.
The two new cells divide a second time to produce four new gametes. These gametes contain one-half of the genetic information needed to form a new individual. Each parent provides one gamete to the process of fertilization, which results in a cell called a zygote with a full compliment of chromosomes.
Offspring produced through sexual reproduction are genetically distinct from both parents, since each of their gametes has a unique combination of chromosomes. Table 2. Weird Science. Voice of the Sea. Further Investigations.
Table of Contents: Growth, Development, and Reproduction. Special Features:. Representative Image:. Further Investigations: What is an Invertebrate? Question Set: What is a Mammal? Further Investigations: What is a Mammal? The number of cells increases by mitosis, and as the embryo develops, the cells begin to differentiate or specialise.
As half of the genetic make-up of the offspring is from one organism and half from another, it is genetically different from its parents. In other words, it shows variation. Reproduction and variation Asexual reproduction Only one parent is needed in asexual reproduction.
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