In rheumatoid Arthritis patients, NK cell levels were abnormally elevated, possibly due to high serum levels of IL-2.
Rheumatoid arthritis (RA), is an autoimmune disease that means our own immune system attacks self healthy cells in the body by mistake, causing inflammation (painful swelling),mainly attacks the joints.
The given study is to investigate the relationship between serum interleukin-2 (IL-2) levels and disease activity.
This study also showed the relationship between absolute numbers of peripheral lymphocyte subsets, autoantibodies, and associated cytokines in patients with rheumatoid arthritis (RA).
The results showed that the number and percentage of NK cells were positively correlated with serum IL-2 levels so, IL-2 can be a reason for elevated level of NK cells
Learn more about Rheumatoid arthritis on
brainly.com/question/16920119
#SPJ4
Ventilation systems are needed in a <span>multicellular organism to actually obtain oxygen and give out carbon dioxide. Without this ventilation system, it would be very difficult for multicellular organisms to survive. It has been also observed that surface diffusion is not enough for a multicellular organism to breath.</span>
1. 
where in a population:
p - the frequency of the <em>A</em> allele
q - the frequency of the <em>a</em> allele
- the frequency of the <em>AA</em> homozygous genotype
- the frequency of the <em>aa</em> homozygous genotype
2pq - the frequency of the <em>Aa</em> heterozygous genotype
A population at equilibrium will have the sum of all the alleles at the locus equal to 1.
2. Conditions:
A. The breeding population must be large
B. No natural selection
C. The mating must occur randomly
D. No mutations to cause changes in allelic frequency.
E. No changes in allelic frequency due to immigration or emigration.
3. By comparing the actual genetic structure of a population with what we would expect from a Hardy-Weinberg equilibrium, we can determine how much it deviates from the baseline provided by the mathematical model. Depending on how large the deviation is, one or more of the model's assumptions are being violated. Thus, we can attempt to determine which one.
The answer is Chordates
Chordates belong to the pylum Chordata of the Animal Kingdom.They have the following characteristics;
Lower vertebrates have a notochord which is a hollow nerve chord that is located dorsally of the animal while higher vertebrates have a vertebral column of bone and cartilage. They have a coelom which is a body cavity that differentiates higher vertebrates into organs and digestive tract.
