Answer:
Explanation:
B. có nhiều hệ sinh thái khác nhau trên trái đất. mỗi hệ sinh thái có một đặc tính riêng và chúng có thể kết nối, tác động qua lại với các hệ sinh thái khác
Answer:
Broad-spectrum antibiotics can cause antibiotic resistance.
Explanation:
- Antibiotics are the substances that inhibit the growth of or kill the bacteria and hence, these are used as medications for the treatment of a lot of bacterial diseases.
- These antibiotics can either be of broad-spectrum or the narrow spectrum.
- The broad-spectrum antibiotics are the ones that are effective against a variety of bacteria, both gram-positive and negative whereas the narrow-spectrum antibiotics are the ones that target only a specific type of bacteria.
- Since the bacteria can mutate very fast and hence, develop antibiotic resistance, the doctors usually avoid prescribing broad-spectrum antibiotics and only use them when the causal bacteria is completely unknown.
- Hence, in the given case the provider prescribes separate medications for both types of bacteria.
It depends on what kind of solution is referred as 0.65 M. If the solution where the red blood cell is present is hypertonic, the red blood cell will shrink. If the solution is hypotonic, the red blood cell will expand. If the solution is isotonic, the red blood cell will not expand or shrink.
Answer:
Genetic drift
Explanation:
Genetic drift is defined as the random change in allelic frequencies from one generation to the other.
Genetic drift is an evolutionary mechanism in which the allelic frequencies in a population change through many generations. Its effects are harder in a small-sized population, meaning that this effect is inversely proportional to the population size. Genetic drift results in some alleles loss, even those that are beneficial for the population, and the fixation of some other alleles by an increase in their frequencies. The final consequence is to <u>randomly</u> fixate one of the alleles. Low-frequency alleles are the most likely to be lost. Genetic drift results in a loss of genetic variability within a population.
Genetic drift has important effects on a population when this last one reduces its size dramatically because of a disaster -bottleneck effect- or because of a population split -founder effect-.
Some facts about Water erosion :
Water erosion is the detachment and removal of soil material by water. The process may be natural or accelerated by human activity. ... Water erosion wears away the earth's surface. Sheet erosion is the more-or-less uniform removal of soil from the surface.
Water and Wind Erosion (cause)
Water erosion is the removal of soil by water and transportation of the eroded materials away from the point of removal. Water action due to rain erodes the soil and causes activities like gully, rill, and stream erosion leading to the downstream effects of flooding and sedimentation.