D. both a and b
homozygous means that the genotypes would be the same. so, homo dominant (ex. RR) and homo recessive (ex. rr) would be considered purebred genotypes
Answer:
b. most sunlight is absorbed before reaching these levels
Explanation:
The role a of a digestive system is
Your digestive system breaks down the food you eat into nutrients such as carbohydrates, fats and proteins. They can then be absorbed into your bloodstream so your body can use them for energy, growth and repair.
Answer:
It is possible since a receptor can activate different signaling pathways in different cell types
Explanation:
In a cell, a receptor bind to a specific ligand to activate a signaling pathway, while the same receptor may bind either with the same or another ligand in another cell type and thus activate another signaling pathway
