The Precambrian time refers to the time 4.5 billion to 542 millions year ago. This period is characterized by having reduced atmosphere and included reduced compounds. Scientists believed that atmosphere at that time was devoid of free oxygen and CO2 was present in excess. Before the complex life evolved on the Earth, the Precambrian Earth's ocean contained dissolved carbon dioxide.
O2 (oxygen) is a covalent compound
Answer:
Going down Burr Hill; the contour lines are close together.
Explanation:
Between Points A and C, the steepest part is going down Burr Hill.
I know that, because the contour lines are so close together.
That means your vertical descent is quite steep compared to the distance you cover horizontally.
False,
In order to start labor, estrogen increases and progesterone decreases.
Estrogens are a class of hormones that are essential for women's healthy sexual and reproductive development. They are sex hormones as well. The majority of estrogen hormones are produced by a woman's ovaries, however minor quantities are also produced in modest amounts by the adrenal glands and fat cells.
Progesterone is a member of the progestin drug class (female hormones). By lowering the level of estrogen in the uterus, it functions as a component of hormone replacement treatment. By substituting for the natural progesterone that some women lack, it helps to initiate menstruation.
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