<span>Within eukaryotic cells, there is a network of organelles which have unique functions.
An organelle is termed as a specialized subunit within a cell which has specific functions and their functions are very vital for a cell to live. Organelles can be identified by microscopy and purified by cell fractionation.
In eukaryotic cells has many types of organelles. Larger organelles which are found in eukaryotic cells are visible with the light microscope, for example, vacuole and nucleus.
Some of the major eukaryotic organelles include plastid, endoplasmic reticulum, flagellum, mitochondrion, vacuole, nucleus and Golgi apparatus</span>
Answer:
Option A, Pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction
Explanation:
Genetics variation allows as organism to evolve in a way to be able to cope up with the existing or changing environmental condition. Now, a Pantala flavescens undergoes sexual reproduction, thus only this creature has the ability among all the given organism to evolve genetically and be able to survive in this environment. All the remaining organisms reproduce asexually and hence there is no variation with in them and hence it would be difficult for these organisms to cope up with changing environment.
Hence, option A is correct.
The human immunodeficiency virus (HIV) that causes the disease known as aids selectively infects helper T cells (CD4+).
This retrovirus also infects macrophages and dendritic cells. When CD4+ T cell numbers decrease below a critical level (due to the killing of this cells with different mechanisms), cell-mediated immunity is lost. As a result, the body becomes progressively more susceptible to infections, leading to the development of AIDS.
<span> HIV can be transmitted only via body fluids like blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk, which means that people usually get or transmit HIV through sexual behaviours and use of the needle. For HIV infection, these fluids must come in direct contact with a mucous membrane or damaged tissue. Another way is to be directly injected into the bloodstream (from a needle for example).</span>

The Correct choice is ~
" At the top of the swing where it briefly stops before changing direction "
before changing the direction, it stops for a while therefore the kinetics energy is almost zero at that particular moment ~
Production of ATP in the absence of oxygen is called anearobic respiration. Under anaerobic respiration,two molecules of ATP is produced from one molecule of glucose. These ATP are used for energy production by the contracting muscles.