D. Darwin's theory of natural selection shows that organisms evolve based on which one's survive the best and thrive.
Answer:
6.
The attached image contains the correct labels.
7.
a. 1
b. 6
c. 3
d. 10
e. 8
f. 4
g. 2
h. 7
i. 9
j. 5
Explanation:
7.
The entire cardiac cycle is as follows:
- Deoxygenated blood enters the right ventricle from the superior and inferior vena cava.
- The right atrium pumps the deoxygenated blood to the right ventricle.
- From the right ventricle, the deoxygenated blood moves to the lungs via the pulmonary artery.
- After gaseous exchange, the oxygenated blood returns to the heart into the left atrium via the pulmonary vein.
- From the left atrium, blood moves to the left ventricle.
- Oxygenated blood is pumped by the left ventricle into the aorta which supplies blood to all parts of the body.
- Deoxygenated blood, collected from the body again enters into the right atrium via the vana cava.
Answer:
The culture might not be stained properly or the culture might be too old.
Explanation:
Gram staining is done to differentiate between gram-positive and gram-negative bacteria according to the difference in their cell wall. In gram staining, the gram-positive bacteria appears violet and gram-negative bacteria appear pink in color.
Therefore if a pure culture contains have both red and purple cocci that it can be concluded that the gram stating was not done properly like too much destaining was done or too much safranin was used or maybe the culture is too old so that cell wall of some bacteria degrades.
The variation in color and markings is beneficial to the orchid plants because it helps the flowers pollinate efficiently (Option C). It is an adaptation.
<h3>What is an adaptation?</h3>
An adaptation is an evolutionary trait that allows an organism to take advantage of survival and/or reproduction.
Orchid color can attract pollinators by mimicking flowers of plant species that live in the same area.
It is an adaptation known as mimetism, which allows them to take an evolutionary advantage.
Learn more about adaptation here:
brainly.com/question/29594
<u>Answer:</u>
<em>Six centromeres are observed in a prophase cell from an insect, there are </em><u><em>20 pairs of chromosomes present</em></u><em>. </em>
<u>Explanation:</u>
<em>Centromeres is defined as the part of the DNA</em> which are held responsible for the directional changing of chromosomes.
And these chromosome gets divided into <em>2 daughter cells while undergoing the process of mitosis and meiosis. </em>
<em>Chromosome is basically defined as a thin structure</em> as of a threadlike which is made out of nuclei acid and protein which is <em>located at the nucleus of various living cells</em>