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=__**Cells**__=

**1. What are the advantages and disadvantages of sexual and asexual reproduction?**
Each form of reproduction has advantages and disadvantages.

In asexual reproduction, the parent's genes split in two. In eukaryotes, organisms with a nucleus, the two new halves replicate through mitosis. In prokaryotes, organisms without nuclei, the two halves replicate through a similar process called binary fission. This means that the parent organisms turns into two and the two new halves grow into new organisms that are identical to the parent organism. Another way of asexual reproduction is budding. Budding is a unique process where the offspring grows on the parent and then falls off to become an independent organism. In all forms of asexual reproduction, the offspring are always genetically identical to the parent organism. Advantages of asexual reproduction is that it is really fast. Disadvantages to asexual reproduction is that due to the fact that the offspring are exact copies of the parent, they have the exact same genetic code as each other. There is no variation. If there are many clones and there is one deadly disease that one organism is prone to, then all the organisms will die because they have the same genetic material.
 * http://www.brainpop.com** **& Foundation Science 2 page 50:**
 * [[image:e2geneticswikia/Screen_shot_2011-12-02_at_11.45.33_AM.png width="370" height="277" caption="Figure 1.1 The process of asexual reproduction"]] || [[image:e2geneticswikia/Screen_shot_2011-12-02_at_11.44.10_AM.png width="371" height="279" caption="Figure 1.2 The offspring have the same DNA as the parent"]] ||

In sexual reproduction, a female egg cell if fertilized by a male sperm cell. Each one of these cells contain a half set of the parents' chromosomes or genes. When the two cells combine, so do the genes. The result is a new unique individual who will inherit traits from both parents. In other words, these are different individuals from the parents. They have some traits inherited from the father and some traits inherited from the mother. Advantages of sexual reproduction are that it is more reliable and produces variations amongst the offspring.
 * http://www.brainpop.com:**

Disadvantages to sexual reproduction is that if one organism cannot find a mate (the same organism of the opposite gender), then the organism cannot produce offspring. If there is a race of organisms close to extinction and there are only one gender of those organisms, then they cannot reproduce because there have to be two of the same organisms but each of the opposite gender for offspring to be produced. Also, sexual reproduction takes a longer time than asexual reproduction.

__**Sources:**__ http://www.brainpop.com/science/cellularlifeandgenetics/asexualreproduction/ Foundation Science 2 for GCSE: pages 50-53 Figures 1.1-1.3: http://www.brainpop.com/science/cellularlifeandgenetics/asexualreproduction/

**2. What are 3 organisms that reproduce asexually and what are 3 organisms that reproduce sexually?**
There are many organisms that reproduce sexually and many organisms that reproduce asexually.

A few of the many organisms that reproduce sexually are:
 * [[image:88037-1.png width="226" height="167" caption="Figure 2.1 Birds"]] || [[image:117570.png width="235" height="174" caption="Figure 2.2 Fish"]] || [[image:104393.png width="235" height="174" caption="Figure 2.3 Monkeys"]] ||

A few of the many organisms that reproduce asexually are:
 * [[image:95939.png width="229" height="174" caption="Figure 2.4 Bacteria"]] || [[image:101579.png width="229" height="174" caption="Figure 2.5 Sponges"]] || [[image:113344.png width="229" height="174" caption="Figure 2.6 Coral"]] ||

__**Sources:**__ http://en.wikipedia.org/wiki/Asexual_reproduction http://en.wikipedia.org/wiki/Sexual_reproduction Figures 2.1-2.6: http://chrome.brainpop.com/search


 * __ADDITIONAL INFORMATION__**
 * __By Lu Yi:__**

Figure 1.1
 * 1. What are the advantages and disadvantages of sexual and asexual reproduction?**
 * Science Foundation page 51 (non-visual part):**

Asexual reproduction is faster than sexual reproduction because the organisms do not need to find a mate. However, asexual reproduction does not produce variations, whereas sexual reproduction does.

Overall asexual is faster and easier than sexual reproduction, because another partner is not needed, and doesn't have to be found. Another advantage of asexual reproduction is that the animal or pollen grains doesn't have to travel in order to propagate the species, which means it can conserve energy and be more discreet. Because genetic information is shared by the two gametes is sexual reprodution, variety is produced in the species. (...) as variety ensures the death of the species with a certain weak element, and the survival of species with an advantageous element. This will create a better species, who is better at surviving. on the other hand, asexual reproduction doesn't allow any type of geneti variation, this is an advantage, because any mutations or "bad" qualities will be passed on, and cannot leave the life chain of that species. Asexual reproduction is more reliable than sexual, because there are less steps to follow and therefor less can go wrong, for instance pollen transfer is very flimsy and since asexual reproduction doesn't need this, it is more reliable.
 * Library.thinkquest.org (partial [useful] text) WARNING: SUSPECTED UNRELIABLE SOURCE:**

__**Sources:**__ http://library.thinkquest.org/22016/contribute/asex_sex.htm Figure 1.1: http://sexual-communication.wikispaces.com/file/view/sex_wiki_1.gif/219221574/sex_wiki_1.gif Science Foundation 2 for GCSE: pages 50-53

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media type="youtube" key="kaSIjIzAtYA" height="315" width="560" From: http://www.youtube.com/watch?v=kaSIjIzAtYA

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