Answer:
Well, the primary distinction between these two types of organisms is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. ... Prokaryotes, on the other hand, have no membrane-bound organelles. Another important difference is the DNA structure.
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>
Answer:
c. Two sister chromatids did not separate into the proper daughter cells during anaphase.
Explanation:
The observed cell is undergoing mitosis which does not include separation of homologous chromosomes. During anaphase of mitosis, two sister chromatids of each chromosome separate from each other. They move to opposite poles. This results in equal distribution of two complete sets of chromosomes to each daughter cell.
However, the failure of two sister chromatids of a chromosome during anaphase would lead to the formation of two abnormal daughter cells. One of the daughter cells would have one extra chromosome (2n+1) while the other would lack one chromosome from the diploid set (2n-1).
The correct answer is that ferns have two part in their life cycle: Diploid phase and haploid phase
The life cycle of a fern has two parts: sporophyte stage and gametophyte stage. The gametophyte stage of ferns are haploid which releases gametes and the sporophyte stage are diploid that produces spores. This kind of life cycle is known as the "alternation of generation".
The answer can be either multicellular organisms or the scientific word of Eukaryotes.
