<h2>Cell Cycle
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Explanation:
Eukaryotes grow and divide by cell cycle.
The main parts of a cell cycle are an ordered series of events – Gap 1 or G1 phase, Synthesis or S phase, Gap 2 or G2 phase, and the mitosis or M phases.
Interphase period (G1, S, G2 phases) - cell grows by size, duplicates its content, replicates its DNA, and finally prepares for mitotic cell division
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Mitosis and cytokinesis - formation of two identical daughter cells
Cell cycle is regulated by regulatory or restrictive checkpoints in the cell cycle which are activated with detection of a defective DNA.
Proliferation of undesired or cells with defective DNA like in case of tumor cells is controlled by the action of suppressing agents like p53 and cyclins.
The tumor suppressor gene protein p53 prohibits division of tumor cells. Cyclins regulate cell cycle by activation of the enzyme cyclin-dependent kinase.
True. Greenhouse gases are composed of many molecular components that provide and are necessary for life to still exist on earth. For example, the carbon dioxide and the others alike. However, when these exceed the necessary level and amount in the atmosphere, they cause tremendous increase in temperature.
The correct terms to fill in the blanks are lateral ventricles and venous sinus blood. Cerebrospinal fluid (CSF) is formed by lateral ventricles and reabsorbed through arachnoid granulations into the venous sinus blood. The CSF is a fluid that is clear and colorless found in the spinal cord and in the brain, generally the central nervous system. The CSF functions as a buffer or a shock absorber for the brain. It provides basic mechanical protection for the brain. Also, it helps in the circulation of nutrients and the chemicals that are filtered and aids in the elimination of waste products.
The place where an organism lives and that provides the things it needs to survive is its habitat.
