Answer:
When patient takes in antibiotics the resistance bacteria gets a competitive survival advantage over the normal sensitive bacteria and hence grows faster.
Explanation:
- Bacteria can acquire resistance by taking in plasmids containing MDR (Multi-Drug Resistance) gene cassettes. The MDR genes produces proteins that can:
- Render the antibiotic ineffective to act on its target by inducing chemical modifications on the drug.
- Promote efflux of the drug from the bacterial cell so that the drug cannot act upon its target.
- When a healthy person ( having no prior exposure to the antibiotic) is infected by bacteria ( both sensitive and resistant varieties):
- A competition develops for the host cells and nutrients between the sensitive and the resistant variety.
- This mutual competition restricts either of the sensitive or resistant bacterial strain to grow profusely.
- When a person (having prior antibiotic exposure), gets infected by bacteria ( both sensitive and resistant varieties) and is exposed to the same antibiotic:
- The sensitive variety, due to its sensitivity towards the drug, gets killed.
- The resistant variety, due to its MDR genes, bypasses the lethal effect of the drug and survives.
- These surviving resistant bacteria can now infect all the available host cells and utilise all the available nutrients without facing any competition and multiply rapidly.
Answer:
b. Menopause
The end or cessation of menstruation is called menopause.
Explanation:
Menopause is the event when menses stop. Climacteric is more adequate to refer to the diseases associated with the decrease of ovarian function that will lead later to the event when menstruation cease, commonly known as menopause.
On the other hand, amenorrhea is the absence of some menstruation periods but during the reproductive period of a woman, and menarche is called to the event when the first menstrual cycle occurs.
Answer:
It would be Active transport.∞←
Explanation:
Answer:
The tabby cat has inherited color traits from both parents and shows amixture of both colors
Explanation:
Answer:
A mutation in the DNA sequence of the gene for brown fur
Explanation:
The mutations are capable of changing the encoded protein product, in this case the gene that encodes for the fur color pigment. This mutation may have occurred during mitosis or meiosis divisions.
If it is a spontaneous mutation that occurred in the germinal line (meiosis) and confers an adaptive advantage, it will increase their frequency in the population.
