During the S phase in the cell cycle, the chromosomes are replicated so that there are two copies. These copies are necessary so that each daughter cell created during the M phase will have an identical copy of the DNA.
Therefore, the answer is A: The DNA must be replicated.
The chromosomes joining, cell membrane expanding, and cytoplasm separating all happen during the M phase (mitosis).
Intercostal Muscles
The muscles of respiration
are muscles that contribute to exhalation and inhalation by causing the contraction
and expansion of the thoracic cavity. However, diaphragm is the main muscle of breathing
while intercostal muscles is one of the most important muscles for respiration.
Intercostal muscles function by manipulating the width of the rib cage and they
are attached between the ribs.
Answer:
lipid, fatty acid, cell membrane
protein, amino acid, enzyme
carbohydrate, sugar, starch
nucleus acid, nucleotide, DNA
