Answer:
A) The pollen grains will be pure red.
Explanation:
Plants have alternation of generations, this means that there are two different stages in their life-cycle: a sexual haploid (n) phase and an asexual diploid phase (2n). These phases occur in different individuals, so there is an haploid plant called gametophyte that carries gametes and after fecundation, it will rise a diploid sporophyte (asexual).
In seed plants, the sporophyte is the plant that we normally see, and the gametophyte is reduced into an organ of the sporophyte. The male gametophyte is the pollen that is produced in the sporangium in anthers (parts of sporophyte). When a pollen grain fecundes a female gametophyte (egg), it will produce a diploid embryo or new sporophyte.
Therefore, if the researcher exposes pollen to both stains, these grain will stain red, because red stain identifies gametophyte tissue.
Answer:
Answer D
Explanation:
Unlike the gain or loss of member through immigration, emigration, or death, the age of a population's members does not effect population size, meaning the correct answer is D.
Answer: A scenario often presented to introductory physics classes is that of a "gravity tunnel" — a tube drilled from one side of the Earth to the other through the planet's center. The answer taught for nearly a half-century for how long a fall through such a hole would take was about 42 minutes and 12 seconds.
Explanation: However, solar and lunar gravity, which also perturb orbiting satellites, would eventually pull you into the tunnel wall anyway [source: Darling ]. Strike a chord: Fun fact: A straight line from any point to any other point through the planet would take the same amount of time to fall through like a tunnel through Earth's center.
Answer:
The correct answer will be option-B (purine).
Explanation:
Nucleic acid structure is made up of monomer unit called nucleotide. Each nucleotide is composed of a five-carbon sugar, a phosphate group and five types of nitrogenous bases.
The nitrogenous bases are categorized in two forms the purines (adenine and guanine ) and the pyrimidines (cytosine, thymine and uracil). The "purines" contain double rings in their structure due to which they appear larger in size than pyrimidines which are made up of single rings.
Thus, Option-B is the correct answer.