The flagella of the eukaryotes is composed of the doublet microtubules. The central bundle of these microtubules is known as the anoxeme. In an axoneme, a single pair of the singlet micortubules is surrounded by the nine doublet microtubules. When the plasma membrane of the flagellum is opened to expose the axoneme, and the radial spokes are broken, it will lead to the elongation of the axoneme,
Answer:
Bacteria and Archaea
Explanation:
The prokaryotes are classified into two domains, the bacteria and the archaea domains. This makes them unique as the other organisms fall into one of the three domains, not in two of them. The prokaryotes come in many different shapes. They all do fall into three categories, bacilli (which are the rod-shaped prokaryotes), spirilli (which are the spiral-shaped prokaryotes), and cocci (which are the spherical shaped prokaryotes).
<span>#1) With reference to the role of oncogenes, explain how the normal controls over the cell cycle can be lost.
Answer: The way that cell cycle can be lost is by going through changes in the activity of cell cycle regulators. Cancer causes different types of mutations. There are two types of cell cycle regulators that can promote the development of cancer:
-Positive Regulators that can be over activated (become oncogenic).
-Negative Regulators (tumor suppressors) which can be inactivated.
I hope it helps, Regards. <span /><span>
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Reproduction is not necessary but is essential in keeping the generations of species going.<span />
Answer:
variation
Explanation:
Genetic variation is what makes us all unique as a result of subtle changes in our DNA. The Theory of Evolution is a process in which organisms change over time as a result of adapting to their environment. Charles Darwin came up with the term Survival of the fittest, in any environment plants and animals from the same species show natural variation in their physical characteristics, like neck lengths in giraffes. Darwin suggested that the plants and animals best suited to the environment will survive and pass on their characteristics to their offspring. Over time, the characteristics of the surviving members of the species will become predominant.
Example: Peppered moth
In London in the 1800's, 98% of peppered moths had light colored bodies and only 2% were dark. The light moths were the same color as the trees so they could easily hide from hungry birds and not get eaten. The dark moths however were easy to see and were eaten. Then came the factories and smoke of the industrial evolution and many trees turned black with soot and suddenly the dark moths were able to survive better as they now looked like the trees and the light colored moths were easier to spot and eat. By 1895 the dark peppered moths made up 95% of the population and the light colored moths only 5%. This is an example of natural selection, because of the gene that makes the moths dark, it allowed them to flourish when the environment changed, they adapted, reproduced and survived.
