Thursday, 14 April 2011

5.5 - Mutation/Sexual reproduction

What is mutation? Benefitial ones? Neutral ones? Any harmful ones?
Sometimes in a genetic sequence (known as DNA) mostly spontaneous changes occur. These changes are usually brought on by various reasons such as radiation, viruses and mutagenic chemicals (Think polution)
Mutations can either be harmful, benefitial or neutral. An example of a mutation for each would be

Beneficial: Though this is not  a proven fact, but an observation on my part, a beneficial mutation could be peoples ears. I have notice that people that live in hotter regions sometimes have ears that stick out of there heads. I think this is due to high temperatures, that since the ears stick out more it creates for surface area to allow the person to remain cooler a little longer.
Neutral: Mexican Tetra, is a blind albino fish (no eyes and no skin pigmentation) that resides in caves in Mexico. Since these fish live in deep dark caves, they've lost their eyesight and colour (no sun to hit them) but they can still find there way around due to  their lateral lines which are highly sensitive.
Harmful: Some hereditary diseases (there was a mutation in the germ cell)


What is sexual reproduction?
Well.. Lets see. Sexual reproduction happens when a man and a woman get together.. JK. Sorry, I'll try and be more proffesional. Ahem. Sexual reproduction  is the creationof a new organism from an older one. How? There are two types of reproduction asexual, and sexual reproduction. (we're only sexual no asexual today)
Artificial selection and selective breeding are the same thing. We use selective breeding alot, for things such as fruits and vegetation and even dog breeds. People will breed dogs and select certain dog for there traits and reproduce them to create the "ultimate" breed. Ex: Labradoodles are a mix of a Labrador and Poodles.

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