Answer: Sphincter muscles
Explanation:
The circular rings of smooth muscles, that can contract to regulate the movement of the smooth muscles that can contract to regulate the movement of food through the gastrointestinal tract are known as sphincter muscles.
These two layers are outer layer and inner layer. The outer layer is longitudinal and the inner layer is circular. They contract rhythmically to squeeze food.
Globin 1 and globin 2 genes of insects are understood to have diverged approximately 170 million years ago, through duplication, from a common globin gene ancestor. The two genes that code for haemoglobin have conserved regions; oxygen-binding and heme- regions. Globin 2 gene has lost the intron region that is still present in the globin 1 gene. The percentage divergence is 7.2% with 20 varying nucleotides.
The correct answers are A and C.
When an individual is reproducing asexually, it means that there is no fusing of two parent cells and meiosis, but that the offspring is produced out of the cells of one parent. This means that the organism is not '' losing time'' by trying to find a suitable mate, which enables the populations to grow at a rapid rate.
However, the offspring are genetically identical to the parent, which means that there is very little genetic variation in the population which can lead to accumulation of harmful mutations and unresponsiveness to changes in the environment.
Coordinates muscles controlling breathing ..
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