Answer: If you're a kid, your heart is about the same size as your fist, and if you're an adult, it's about the same size as two fists. Your heart beats about 100,000 times in one day and about 35 million times in a year. During an average lifetime, the human heart will beat more than 2.5 billion times.
Answer:
are densely packed with numerous mitochondria.
Explanation:
Mitochondria are considered as the energetic centers of the eukaryotic cells. These organelles (mitochondria) produce energy in the form of Adenosine Triphosphate (ATP) through the mechanism of cellular respiration, i.e., mitochondria are the organelles where aerobic phases of cellular respiration occur. In presence of oxygen, mitochondria convert chemical energy obtained from foods to ATP, which is the energy coin that cells use to carry out all their metabolic processes (e.g., reproduction, growth, development, etc). Thus, cells with high metabolic requirements need to have many mitochondria in order to produce more ATP.
Answer/Explanation:
The replication of DNA is semi-conservative, as each new molecule of DNA inherits one of the parental strands each, and one new strand each. DNA is replicated using the enzyme DNA polymerase, which synthesises a new strand by adding nucleotides in a sequence through complementary base pairing with the template strand. This occurs before the mitosis stage of the cell cycle, where the cell divides. Before this cell division happens, the cell has to pass certain checkpoints controlled by enzymes which ensure environmental conditions are optimal for dividing, and that the new DNA is free from errors.