Darwin’s Finches: Darwin observed that beak shape varies among finch species. He postulated that the beak of an ancestral species had adapted over time to equip the finches to acquire different food sources. This illustration shows the beak shapes for four species of ground finch: 1. Geospiza magnirostris (the large ground finch), 2. G. fortis (the medium ground finch), 3. G. parvula (the small tree finch), and 4. Certhidea olivacea (the green-warbler finch) the Grants measured beak sizes in the much-reduced population, they found that the average bill size was larger. This was clear evidence for natural selection of bill size caused by the availability of seeds. The Grants had studied the inheritance of bill sizes and knew that the surviving large-billed birds would tend to produce offspring with larger bills, so the selection would lead to evolution of bill size. Subsequent studies by the Grants have demonstrated selection on and evolution of bill size in this species in response to other changing conditions on the island. The evolution has occurred both to larger bills, as in this case, and to smaller bills when large seeds became rare.
<span>Translation
</span>Remember that transcription happens in the nucleus as it changes from DNA
to mRNA. In translation,
the mRNA first has to leave the
nucleus and go into the cytoplasm of the cell.
The process of translation actually occurs in the cell’s ribosomes.
<span>
</span>The process of translation uses the genetic code on the mRNA strand to
direct the construction (making) of a protein molecule. <span>
</span>1. A ribosome attaches to an mRNA
molecule in the cytoplasm.<span>
</span>2. As each codon passes through the
ribosome, tRNA molecules bring the matching amino acids into the ribosome. Each tRNA has a set of 3 unpaired nitrogenous
bases called an anticodon which matches up with the codon coming through the
ribosome. So one end of a tRNA has an
anticodon and the other end carries the amino acid which is how the code is
translated.<span>
</span>3. The ribosome and the rRNA
molecules it contains attach the amino acids together as they are being
translated. The protein chain will keep
growing until the ribosome reaches the stop codon on the mRNA. At that point, translation is done and the
ribosome lets go.
Hope this helps!!!
B it will be exactly 100 grams
Answer:
Megaspore—2n.
Explanation:
Angiosperms are the fruit bearing plants and reproduce by the process of sexual reproduction. The chromosome number are specific at each stage of the cell cycle of the angiosperms.
Microspores , egg are haploid. Zygote is diploid in nature. Megaspores get germinate into the female gametophytes and these are haploid in nature. Megaspores are also haploid in angiosperms.
Thus, the correct answer is option (b).
