Answer:
Dinosaurs are the extinct organisms that belong to the class reptilia. Dinosaurs are the most advanced and bulkier reptiles at the history time and they were overspecialized in their environment.
The dinosaurs extinct rapidly due to the change in the external conditions and the volcanic eruptions that occur at the dinosaurs time. The recent searcher claims that asteroid impact and massive volcanic eruption leads to the dinosaur extinction. The fossil evidence and the presence of the specific basalt and other chemicals are found in the volcanoes and in the asteroid.
Answer:
<em>C: After 1 hour, the pH of the solution in the PEPCID AC beaker was 9.2 and the pH of the solution in the Alka-Seltzer beaker was 8.3</em>
Explanation:
The degree of acidity or alkalinity/basicity of a substance is its pH. The value of pH ranges from 1 to 14 with the former being extreme acidity and the latter being extreme alkalinity while pH 7 is considered neutral.
Hence, any pH below 7 is considered acidic and above 7 is considered alkaline.
Reactions involving equal volumes of an acid and a base can end in acidic, alkaline or neutral pH depending on the strength of the acid/base involved;
- Equal volumes of strong acid with strong base will result in neutral pH
- Equal volumes of weak acid with strong base will result in alkaline pH
- Equal volume of strong acid with weak base will result in acidic pH
If substance A and B reacts with equal volume of the same acid under the same condition and the end result of A is a solution with pH of 9.2 and that of B is a pH of 8.3, it simply means substance A is a stronger base than substance B.
<em>Hence, the only outcome that supports the hypothesis that a tablet of PEPCID AC can neutralize more stomach acid than a tablet of Alka-Seltzer is that the pH of the solution in the PEPCID AC beaker was 9.2 and the pH of the solution in the Alka-Seltzer beaker was 8.3 after being subjected to the same condition.</em>
If an indigestion is due to excess stomach acid, the only way to reduce the acidity is to consume a substance that will decrease the degree of acidity in the stomach. This means that the patient will need to consume something that is alkaline in order to increase the pH.
Answer:
Chromosomes were first named by cytologists viewing dividing cells through a microscope. The modern definition of a chromosome now includes the function of heredity and the chemical composition. A chromosome is a DNA molecule that carries all or part of the hereditary information of an organism. In eukaryotic cells, the DNA is packaged with proteins in the nucleus, and varies in structure and appearance at different parts of the cell cycle.
Explanation:
Cells reproduce genetically identical copies of themselves by cycles of cell growth and division. The cell cycle diagram on the left shows that a cell division cycle consists of 4 stages:
G1 is the period after cell division, and before the start of DNA replication. Cells grow and monitor their environment to determine whether they should initiate another round of cell division.
S is the period of DNA synthesis, where cells replicate their chromosomes.
G2 is the period between the end of DNA replication and the start of cell division. Cells check to make sure DNA replication has successfully completed, and make any necessary repairs.
M is the actual period of cell division, consisting of prophase, metaphase, anaphase, telophase, and cytokinesis.
