Groundwater is defined as water that is found beneath the surface of the earth in conditions of 100 percent saturation (if is less than 100 percent saturation,then the water is considered soil moisture).Ninety-eight percent of earth’s available fresh water is groundwater
A
Before meiosis begins, during S phase of the cell cycle, the DNA of each chromosome is replicated so that it consists of two identical sister chromatids, which remain held together through sister chromatid cohesion. This S-phase can be referred to as "premeiotic S-phase" or "meiotic S-phase".
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.
Answer:
Thelarche
Explanation:
In females, thelarche represents the start of puberty and as such it marks the beginning of the secondary development of the mammary glands known as breasts. This pubertal development usually occur in females that are between the ages of 8 years and 12 years due to the secretion of hormones such as estrogen.
In this scenario, Emily's body starts to develop secretory glands at the end of the milk ducts in the breasts. Based on the given information, we can say that Emily is most likely to be in the thelarche stage because she is beginning to experience breast budding.