<span>It took over 200 years for the "cell theory" to be formalized and accepted. Hooke and Leeuwenhoek were early microscopist's.... but at the time the nature of matter, the belief in spontaneous generation, and the idea there were little worlds within little worlds ad infinitinum was popular. The discovery of the periodic table and establishment that atoms were real, the demolishing of spontaneous generation, all happened at the time that Schwann and Schleiden (and others) were working with better microscopes, better ideas about the material world, and better observations...... thus the cell theory.
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Answer:
a is the answer the the following question
A female fox is called a vixen
Answer:
<u>3) Uncontrolled cell division occurred as a result of gene mutations</u>
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Explanation:
Spontaneous modifications within the genome may occur during the process of cell division. When copies of the DNA inside the cell are made, these mutations cause errors; and can include small single nucleotide polymorphisms, and large scale additions or deletions across multiple genes.
Some, like somatic mutations, exist only inside vegetative (body) cells, that cannot be passed onto offspring. This is caused by several factors like
- UV radiation,
- chemical mutagens,
- infective agents
UV radiation damages strands of DNA, by causing dimers to form; here, consecutive nucleotide bases covalently bond instead of those on the complementary strand. This conformational change causes errors in DNA proofreading and repair mechanisms where bases are not well-incorporated into the strand- tumors (clumps of uncontrolled cell growth) may form, resulting in melanoma, a type of skin cancer.
Crossing over and individual chromosone assortment