They have different types of cell walls and cell membranes.
That the Red flowers are a dominant trait, and the white flowers would be recessive.
The Red Flowers are Homogenous Dominant
In a punnet square, The Genotype ratio for the red flowers would be 2:2
The phenotype would be 4:0
For the white flower
The Genotype would be 1:1
and the phenotype would be 1:0
The white flowers are Homogenous recessive
The presence of palpable lymph nodes.
Lymph nodes are relatively large in children, and the supperficial ones often are palpable even when the child is healthy.
