Recall the endosymbiosis hypothesis and recall endosymbiosis. Remember that the very first cell was a prokaryotic cell. Which engulfed chloroplast precursors and mitochondria. We all come from these cells. And how we evolved over time shows the relationship. I'm a bio major hope I helped
Drinking water shortages? Water across the world isn't purified which without purification doesn't quench thirst.
Answer:
Option (A).
Explanation:
Estrogen hormone is important for the regulation of the female menstrual cycle and their growth and development. Insulin is an important hormone that regulates the blood glucose level.
The hormones insulin and estrogen is placed in the mixture of 2:1 hexane/water. Insulin is hydrophilic molecule and can easily dissolce in water. Estrogen is a hydrophobic molecules and easily dissolve in hexane.
Thus, the correct answer is option (A).
<h2>DNA </h2>
Explanation:
1) Experiment done by Griffith:
- Griffith used two related strains of bacteria, known as R and S
- R bacteria were nonvirulent, meaning that they did not cause sickness when injected into a mouse whereas mice injected with live S bacteria developed pneumonia and died
- Griffith tried injecting mice with heat-killed S bacteria (that is, S bacteria that had been heated to high temperatures, causing the cells to die), the heat-killed S bacteria did not cause disease in mice
- When harmless R bacteria were combined with harmless heat-killed S bacteria and injected into a mouse, not only did the mouse developed disease and died, but when Griffith took a blood sample from the dead mouse, he found that it contained living S bacteria
- Griffith concluded that the R-strain bacteria must have taken up what he called a transforming principle from the heat-killed S bacteria, which allowed them to transform into smooth-coated bacteria and become virulent
2) Experiment done by Avery:
- Avery, McCarty and MacLeod set out to identify Griffith's transforming principle
- They began with large cultures of heat-killed S cells and, through a long series of biochemical steps progressively purified the transforming principle by washing away, separating out, or enzymatically destroying the other cellular components
- These results all pointed to DNA as the likely transforming principle but Avery was cautious in interpreting his results
- He realized that it was still possible that some contaminating substance present in small amounts, not DNA, was the actual transforming principle
3) Experiment done by Hershey and Chase:
- Hershey and Chase studied bacteriophage, or viruses that attack bacteria
- The phages they used were simple particles composed of protein and DNA, with the outer structures made of protein and the inner core consisting of DNA
- Hershey and Chase concluded that DNA, not protein, was injected into host cells and made up the genetic material of the phage
Answer:
Cactus spines
Explanation:
The cactus spines keep predators away and prevent different organisms from eating it. This helps it to survive in the desert. Another adaptation is very thick, waxy cuticle help to reduce water loss by evaporation.
