Answer:
<h2>False</h2>
Explanation:
Natural killer cells (NK cells) are a type of lymphocyte and also a component of innate immune system. NK cells play various functions in immune system and they play a major role in the host-rejection in virally infected cells.
NK cells are activated in response to interferons and also by various other responses. NK cells work to by secreting IFNγ and TNFα. Natural killer cells play a very important role in early host defense against viruses.
A diploid cell contains two complete sets of chromosomes, while a haploid cell only one set.
Species could compete for water, food, land, etc.
Answer:
They release chemical messengers to communicate with cells they may or may not be in direct contact with.
Explanation:
Unicellular organisms such as bacteria or yeast, 'talk' to each other through the release of chemicals. In bacteria, this is known as quorum sensing which allows them to determine the surrounding bacterial population density. In yeast, one of the more popular pathways is known as the mating factor pathway, which allow the organisms to find mates. Whereas, in multicellular organisms (such as humans), this chemical release allows for cell-cell co-ordination which keeps the system functioning correctly.
