Answer:
c. ¼ heavy, ¾ light
Explanation:
DNA replication follows semi conservative model which means that both the strands separate during replication and the newly formed DNA molecule has one old and one new strand. If instead of semi conservative, conservative mechanism is used, old strands will not separate from each other and the two newly synthesised DNA strands will come together to form a DNA molecule.
Here the cells were first grown in heavy 15N medium so all the DNA molecules had 15N and thus were heavy. Then the cells were transferred to 14N medium where only lighter 14N were available for replication process.
In first generation, 14N DNA molecules were synthesised from 15N DNA molecules so 1/2 DNA molecules were 15N and other half were 14N. In the second generation, 14N molecules will give rise to new 14N molecules and 15N molecules will also give rise to 14N molecules hence 1/4 molecules will be 15N (heavy) and 3/4 will be 14N (light).
It's definitely not A. since the toxins would kill butterflies. B. doesn't seem relevant. C. doesn't make sense because the toxins in the pollen are to protect the corn not to make new strains. So, the answer would be D. The carbon dioxide level would increase in the area. Hope this helps!
There are three major types<span> of blood vessels: the </span>arteries<span>, which carry the blood away from the heart; the </span>capillaries<span>, which enable the actual exchange of water and chemicals between the blood and the tissues; and the </span>veins<span>, which carry blood from the </span>capillaries <span>back toward the heart.</span>
Answer:
The hypothalamus is responsible for maintaining the body's internal balance (homeostasis) by stimulating or inhibiting major bodily functions such as the heart rate and blood pressure, body temperature, fluid and electrolyte balance, appetite and body weight, sleep cycle and function of the gastrointestinal track. The hypothalamus is also considered the master regulator of the endocrine system; Regulatory hormones secreted by the hypothalamus are transported by the hypophyseal-portal system to the anterior and posterior pituitary, prompting the release of secondary hormones that can affect various organ functions.
Explanation: