Answer:
Spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes.
Darwin’s
research showed that finches beaks are different to fit their food source. It
also started the theories of evolution and natural selection. The
Grant’s research on the Galapagos Islands showed that evolution exists and can
happen over a course of two years. They proved Darwin’s theories are true. Since
all the plants and animals are native to the islands, they had to adapt to the
new food source and climate. Beaks, size, etc. are all changes made to these
organisms to be able to live on the islands.
The Galapagos Islands are located in Ecuador and
sit on the Pacific Ocean. <span>The Galapagos Islands were formed from 3 million
to 5 million years ago. Volcanic eruptions typically shield volcanoes formed
the islands. They are located over a “particularly hot mantel” that causes
volcanic activity. The outcome of many eruptions were islands because the left
overs were pushed to the surface. The Galapagos islands are pretty big reaching
an area of 3,093 miles. The temperatures range from 69 to 84 degrees creating a
typically warm climate. </span>
Darwin studied medicine at age 16, but became
fascinated specimens around the globe. He developed theories of natural
selection and evolution. While he was on the Galapagos islands, he studied
thirteen different species of finches.
He observed finches and different beak
structures. He observed their ability to consume foods such as nuts, bugs, and
fruit. He concluded all were related to their beaks. For example, long, slender
beaks are good to reach in the flowers of a cactus.
<span>Charles concluded that the finches beaks are
examples of adaptive radiation. To fit in the island, they had to adapt to the
conditions. This lead to Charles’ theory of natural selection. </span>
Charles came to the conclusion of evolution and
natural selection. Natural selection is the process where organisms adapt to their environment to survive and
produce more offspring. Evolution is where different kinds of living organisms
are thought to have developed. These theories have changed science forever and
leave today’s scientists marveling of his theories.
I hope this helps:)
Background. Plants and animals depend on one another for survival in all of Earth's many habitats. ...
Pollination. Pollination is necessary for plants to create new seeds. ...
Propagation. Another way that animals help plants is by dispersing their seeds to new territory. ...
Fertilization.
Hpe this helps :3
Answer:
The nucleic acid is a macromolecule present in living systems in the form of either DNA or RNA, whose molecule consists of many nucleotides which are linked with each other to form long chains. The presence of DNA or RNA in an individual promotes continuity of life. The variability and complexity of nucleic acid are dependent on its constituent molecules as, sugar, a phosphate group, and a nitrogenous base. However, two monocyclic nitrogenous bases were classified purines (adenine:A, guanine:G) and pyrimidines (thymine:T, cytosine:C, and uracil:U).
In addition, RNA is a single-stranded structure which differs from DNA in two aspects, the sugar content of RNA is ribose, and pyrimidine base uracil replaces the thymine base of DNA. A ratio between two strands of DNA can be calculated by using Chargrff's rule which states that "DNA from any cell of all organisms possess a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases'.
The purine to pyrimidine ratio in RNA with different bases is given below in the following table:
Presence of single strand in RNA does not follow chargaff's rule and alters the purine: pyrimidine ratio. The above ratio of each base in the given information is not equal, due to which the ratio of purines to pyrimidines is different. The ratio of DNA and RNA is not equal because DNA has its complementary DNA strand. However, bases in RNA might vary due to its single-strandedness property, but its ratio is dependent on the species.
Therefore, it can be concluded that the ratio of purines to pyrimidines is dependent on the species due to its genetic makeup. Hence, option (c) is correct.
