<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
A model for a company's revenue from selling a software package is R(p)=-2.5p² + 400p, where p is the price in dollars of the software. What price will maximize revenue? Find the maximum revenue.
Answer: p = $80, R = $16,000
Step-by-step explanation:
The maximum is the y-value of the Vertex.
Step 1: Use the Axis-Of-Symmetry (AOS) formula to find x:
x=
R(p) = -2.5p² + 400
a= -2.5 b=400

= 
=80
∴ In order to maximize the value, the company will sell the software package for $80
Step 2: Find the maximum by plugging the p-value (above) into the given equation.
R(80) = -2.5(80)² + 400(80)
= -16,000 + 32,000
= 16,000
I'm pretty sure it would be D... If that's wrong I'm sorry.
Atmosphere
I hope this helps you have a great day!
Answer:
<h2>Food is scarce year-round</h2>
Explanation:
Ectotherm, called cold-blooded animals, whose regulation of body temperature depends on external sources, such as sunlight or any other environmental source.
Example of Ectotherm are: fishes, amphibians, reptiles, and invertebrates.
Endotherm -called warm-blooded animals; those maintain a constant body temperature independent of the environment.
Example of endotherms ; include the birds and mammals and some fish are also endothermic.
Costs and Benefits of Endothermy
By Increasing the rate of metabolism is especially energy intensive. As a result, endothermic animals typically need more food than ectothermic animals.