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What scientist contributed significantly to the theory of evolution? Explain.
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Charles DarwinHe was the scientist behind the idea of natural selection and survival of the fittest.
He was fundamental in the development of the theory of evolution. He made his natural selection theory of evolution. |
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What is an adaptation?
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Specific structures, functions and behaviours that increase an organisms chances of surviving, at least until the organism is able to reproduce.
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What is natural selection?
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Natural selection is the process by which the environment 'selects' favourable characteristics, reducing the frequency of unfavourable characteristics. This means that after many generations of selection, a species becomes better adapted to its environment.
This is very similar to survival of the fittest. |
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What is a mutation?
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A mutation is any spontaneous change in a gene or chromosome that may produce an alteration in the characteristic for which it codes.
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What is speciation?
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The formation of a new species.
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What is a species?
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A group of organisms that normally interbreed in nature to produce fertile offspring.
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What is survival of the fittest?
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A natural process resulting in the evolution of organisms best adapted to the environment.
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What was Lamark's contribution to evolution?
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In 1809, Lamark suggested that - organs are improved when used repeatedly and wekeaend when not used. These changes are called acquired characteristics.- organisms adapted through their struggle to survive- And improvement or weakness developed due to the environment is passed on through reproduction to the next generation of individuals
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What is the structure of DNA?
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DNA is in the shape of a double helix.
It consists of the uprights of 5Carbon sugars and phosphate units. It has the "rungs" of nitrogen bases. The nitrogen bases are Adenine, Thymine, Cytosine and Guanine. |
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What are the complementary base pairs?
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Adenine pairs with Thymine.
Guanine pairs with Cytosine. |
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What is a gene?
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A hereditary unit that controls a particular characteristic.
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What is a chromosome?
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The structures that genes are located on. They are found in the nucleus of your body cells.They are long, coiled, thread-like structures made of DNA and protein.
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What are the total number of chromosomes in a diploid cell of a human?
The number of homologous pairs in a human? The number of chromosomes in each gamete (the number in a haploid cell? |
46.
23 23 |
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What is a diploid cell?
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A cell that contains two chromosomes (2N) of each type.Eg. cells that make up your muscle, nerves, skin, bone, fat, blood, all of your organs and most other cells.
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What is a haploid cell?
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A cell containing only one set of chromosomes (n).Eg. a gamete
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