There may be some strains of bacteria that are naturally resistant to these antibiotics, or there may be some that mutate to become resistant. This means that as antibiotics are used more and more, those that can be killed using the antibiotics die out, but those that are resistant will remain, and will reproduce. Over time, it will be the resistant species that predominate.
- Oxygen cycle is the cycle which maintains the level of oxygen in the atmosphere.
- Oxygen from the atmosphere is used up during combustion, respiration and in the formation of oxides of nitrogen.
- This oxygen is returned to the atmosphere by lithosphere.
- This forms the oxygen cycle in nature.
Hope you could get an idea from here.
Doubt clarification - use comment section.
Answer:
The students with the purple shirts are moving through the gym doors most often.
Explanation:
- The students with the purple shirts represent potassium ions
- Potassium ions move freely across the membrane by passive transport and are important in maintaining membrane potentials
- The movement of sodium ions is through active transport therefore this is a process that requires energy (ATP) and thus these ions are less likely to move across the membrane often
Answer:
Cells of skin, for instance, have highest mitotic index.
Explanation:
Many cells are capable of dividing rapidly. <u>For example</u>, in plants, the cells near the root tip in the apical meristem divide rapidly to push through the soil because the root cap detects the gravity and direct rapid division and growth of cells near the tip.
If we take muscle, skin, kidney, and lung as examples that are given in real question, <u>skin cells have the highest mitotic index because they need to get replaced most frequently</u>.
