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after dna replication during s phase of interphase, each chromosome has a copy and the cell is now 4n. we call these identical pairs and they are held together by a

a. homologous pairs; centrosome.
b. sister chromatids; histone.
c. homologous pairs; histone.
d. sister chromatids; centromere.

The correct answer is D sister chromatids;centromere

Explanation:

After DNA replication during s phase or synthesis phase of interphase of the cell cycle,each chromosome has a copy and the cell that is newly formed is now 4n.

      We cal these identical pairs sister chromatids and they are held together by a centromere

the abdomen (less formally called the belly, stomach, tummy or midriff) constitutes the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. the region occupied by the abdomen is termed the abdominal cavity. the stomach secretes acid and enzymes that digest food. ridges of muscle tissue called rugae line the stomach. the stomach muscles contract periodically, churning food to enhance digestion. the pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.

hi~~

i would say that hybridization occurs frequently in nature, because there are many types of hybrids that have occurred naturally, such as the mule (male donkey + female horse)