A. They impede fish migration and spawning
Mechanical digestion is the breaking down of food into smaller pieces physically. Mechanical digestion begins in the mouth as the food is chewed.
but in the case of chemical digestion, it breaks the food into simpler nutrients that can be used by the cells. Chemical digestion begins in the mouth when food mixes with saliva.
for more refer to this:
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and ur welcm
Answer:
c. secondary consumer level
Explanation:
Most secondary extinctions are due to direct bottom‐up effects: consumers go extinct when their resources are lost. Secondary extinctions due to trophic cascades and disruption of predator‐mediated coexistence also occur.
Answer:
The correct answer is option 3, that is, blastomeres.
Explanation:
A kind of cell formed by cleavage of the zygote post-fertilization is called a blastomere, it is an important constituent of blastula formation. The formation of blastomere starts instantaneously post-fertilization and is carried through the initial week of the development of embryo. The division of zygote after fertilization is regarded as the first mitotic outcome of the fertilized oocyte. These mitotic divisions take place spontaneously and lead to a grouping of cells known as blastomeres.
No not if there are factory or houses that causes stuff like global warming