About 90% of our DNA is the same.
Answer:
Ancient landmasses
Explanation:
The same fossils being found in widely separate areas can help scientists infer the geography of the continents of that time.
For example: Africa and South America used to be connected during the Permian Period.
Scientists can confirm this because both continents are home to similar fossils.
Step one: Travel approximately 18 inches up the underside of the branch you are removing. Cut up about halfway through the branch.
Step two: Move to the top side of the branch. Choose a location an inch further out from your first cut. Carefully cut down until the branch breaks free.
Step three: Find the branch collar on your trunk. This is stem tissue around the base of the branch. . Make a complete cut with a 45-degree angle kicking out from the base of the tree.
(SOURCE Chris Lambton) Add your vocabulary words in along the way if you decide to use my answer.
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.