# GATE2020: 28

Which of the following statements about immune response are $CORRECT$?

1. $T$ cells are activated by antigen-presenting cells
2. Foreign peptides are not presented to helper $T$ cells by Class $II$ $MHC$ proteins
3. Dendritic cells are referred to as professional antigen- presenting cells
1. $P$ and $R$ only
2. $P$ and $Q$ only
3. $Q$ and $R$ only
4. $P, Q$ and $R$
in Others
edited

## Related questions

1
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2
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3
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4
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The $DNA$ sequence shown below is to be amplified by $PCR$: $5{}'$ GCTAAGATCTGAATTTTCC$\dots\dots$TTGGGCAATAATGTAGCGC$3{}'$ $3{}'$ CGATTCTAGACTTAAAAGG$\dots\dots$AACCCGTTATTACATCGCG$3{}'$ Which one of the following pair of primers can be used for this amplification? $5{}'$ ... $5{}'$ GCGCTACATTATTGCCCA$3{}'$ $5{}'$ GCTAAGATCTGAATTTTC$3{}'$ and $5{}'$ TGGGCAATAATGTAGCGC$3{}'$