Proteins
The internal and external
regulators are mostly composed of proteins. These regulators plays a role in
many cells, they control, regulate and support the process in which involves
the cell cycle. The cell cycle is where each cell undergoes cell division,
either mitosis or meiosis. Thus, these regulators react to their designated
areas, internal regulators responds to the internal stimuli and external
regulators responds to the external stimuli. These regulators help and support
the cell cycle as much as not to cause any irregularities during the process.
Answer:
The answer is <em><u>D.
</u></em>
Explanation:
Viruses can evade the processing and presentation of antigens, for example by interfering with the expression of MHC class I proteins, although this increases their susceptibility to be detected by natural killer cells (NK). However, some members of the herpesvirus, papillomavirus, retrovirus, poxvirus and flavivirus families have also developed strategies to escape the attack of NK cells and promote their survival, inhibiting cell apoptosis. Finally, some pathogens often change surface antigens frequently, as in the case of influenza viruses (orthomyxovirus).
The human immunodeficiency virus (HIV) affects CD4 + T cells and degrades the host's ability to counterattack with a strong cell-mediated immune response. There are so many tactics of immune evasion used by HIV, which have so far hindered the development of an effective vaccine.
Answer:
12. In our somatic (body) cells, we have 2N chromosomes, but in our sex cells (sperm & eggs), we have half the number of chromosomes, which is N chromosomes
Explanation:
1: There's no image shown, but:
2. The adaption of the owl butterfly shows the improve the chances of survival because of the appearance of the butterfly (especially the eyes) makes the animals who likes to eat butterflies think it's an owl instead, and not to be bothered with it, giving the butterfly more time to escape, eat and survive.
Answer:
B
Explanation:
the sound waves cause the eardrum to vibrate
