Answer:
Estuaries filter out sediments and pollutants from rivers and streams before they flow into the ocean, providing cleaner waters for humans and marine life.
The bacteria which had mutation became resistant to the antibiotic and survived and keeps on increasing, promoting natural selection.
Explanation:
The bacteria rapidly divide, the chances of mutation in the gene increases manifold.
The strains of bacteria causing tuberculosis and staph infection got mutated at DNA level such that they became resistant to antibiotics when tested those susceptible did not survive. These mutations were not harmful to bacteria and the resultant bacteria survived.
These bacteria which survived and proliferated as the environment was in their favour.
Thus, Darwin's Theory of Natural Selection is acceptable here as it says if a mutation is occurring towards the increase in population, they will be selected ones.
Answer and Explanation:
The cell division cycle is responsible for increasing and maintaining cell number and size. This cycle is an essential feature of living organisms. There are four phases of cell division mitotic phase (M phase), growth phase 1 (G1), growth phase 2 (G2), and synthesis phase (S). One phase of the cell cycle ends, and the other starts; this is named a phase transition—a unidirectional alteration in the cell cycle phases. During G1, G2, and S phase cell grows and during the M phase cell divides. There are two models of cell reproduction as the clock model and the domino model. The domino model implies that cell division phases must occur in a distinct order and at a definite time. The domino model recommends that the cell cycle events are independent, while the clock model shows that the effectiveness of mitosis entrance was not persuaded by other actions.
The four types of macromolecules in cells are nucleic acids, lipids, proteins, and carbohydrates.