It takes about one minute for a blood cell to make a complete circuit of the human body.
Answer:
With respect to the composition of DNA, in an analysis it can be found that the proportions of nucleotides are A + C = G + T (option a).
Explanation:
The proportion of nucleotides in a DNA molecule can be established according to the sequence of these nucleotides on both complementary strands, since the purinic bases of one strand are complemented by the pyrimidinic bases of another:
- <em>Adenine is complemented with Thymine A=T</em>
- <em>Guanine is complemented with Cytosine G=C</em>
From this we can deduce that in a DNA molecule with two chains there will be the same amount of adenine and thymine, as well as the same number of guanine with respect to cytosine, so:
<em> A + C = G + T</em>
An example of this would be a known DNA molecule (hypothetical), with 5 molecules of Adenine and 7 molecules of Guanine. In this case there are 5 Thymines, complementary with Adenine, and 7 Cytosines like Guanine:
<em> A + C = G + T</em>
<em> 5 + 7 = 7 + 5</em>
Answer: The study of plant varieties.
Explanation:
This question relates to the studies that Gregor Mendel, founder of modern genetics, performed at the University of Vienna.
Experimenting on pea plants, Gregor Mendel was able to establish a lot of the rules of heredity that we know today even though his research was not fully appreciated or understood during his own life.
He credited the study of plant varieties to have been most crucial to his final analysis because farmers had been crossbreeding varieties for millennia to bring about better traits in plants.
Answer:
D.The light-dependent reactions absorb sunlight and transfer the energy to electrons.
Explanation:
Firstly, the organelle that was described as small green organelle inside a cell as noticed by Quinlin is the CHLOROPLAST. Chloroplast is an organelle present in the cells of green plants, in fact, it makes plants green. Chloroplast is the organelle where the unique process of PHOTOSYNTHESIS occurs in plant cells.
However, the photosynthetic process is divided into stages namely: light-dependent and light-independent stages. The light dependent stage, which involves the production of ATP (energy carrier) and NADPH (electron carrier), must PRECEDE the light independent stage or Calvin cycle. Chloroplast contains a pigment called CHLOROPHYLL, which absorbs light energy from the SUN in order to power the light dependent stage of photosynthesis.
Hence, the light-dependent reactions, which absorb sunlight and transfer the energy to electrons must occur first in the organelle.